Tag Archives: aridity

The New Arid Regions of the United States

The southwest and states east of the Sierras magnify the effects of global warming in the intensity of their aridity. But global warming reveals a new relation of regions to overheating, and reveals the depths of inflexibility to accommodate water scarcity, as well as the tragedy of its effects. As aridity of the soil and reduction of groundwater reaches unprecedented scales, our passivity is accentuated as we are suspended before maps that try to visualize unprecedented aridity magnified by global warming and its magnifying effects.

For the cascading effects of warming on the land and environment might be mapped in ways that cannot essentialize the greater “aridity” of the region, but the effects of increased aridity of soil, air moisture, and dry air on a region that we have remade into a region of food supplies, agriculture, and livestock, but, beyond, on hydropower. While the Colorado mountains long provided an effective basin to gather rainwater for western states that have been funneled to state reservoirs for agricultural irrigation, the man-made irrigation networks were drying up as the snowpack determinedly fell, and warmer temperatures evaporated what snowpack fell.

The logic of this longstanding pattern of appropriation of water from across the Colorado Basin was in a sense begun with the Hoover Dam, but was, writ large, organized by very process of appropriating water rights to redistribute water that had been enshrined in California from the turn of the century, circa 1914 and the policies of filling reservoirs to redistribute water rights. While we have considered appropriative water rights a distinct feature of how water is redistributed unique to the Golden state, the appropriation of water rights by reshuffling of water in state’s now precarious supplies how diverts over 99 million acre feet of surface water diverted along the Sacramento and San Joaquin Rivers to farmland, created a powerhouse of national agriculture. Much of the 75 million acre feet that flow from reservoirs across the state evaporates before it arrives at crops, however–far more that actually reaches the farms or cities.

–and the growing heat of the Great Plains have likewise diminished surface flow of the Colorado Basin already reduced by diminished rainfall. The increasingly warmer atmosphere of recent years has created a new “Arid Region” of the United States, of even greater aridity than when it was first mapped by John Wesley Powell in 1890, and the renewed aridity of the region not only challenges the calculus of water distribution according by appropriative rights that is structured by the Interstate Compact, but the very logic of redistributing water.

The past two decades have seen the departure of seven trillion gallons from Lake Meade, the largest reservoir on the Colorado River, holding rainflow from the Upper Basin before it crests the Hoover Dam. The drop will trigger hydrologic stresses across western states, as ever ever-increasing amounts of water are sucked up into drying out air and atmosphere, requiring more abundant irrigation of croplands and grazing grounds. This new and expanded “Arid Region” suggests a return of the repressed, returning at even greater scale and aridity to haunt the nation by a lack of groundwater again.

Evapotranspiration Rates in Colorado River Basin, Landsat 13

that is not to say it ever left. But the solutions of diversion have been undermined by the cascading effects of climate change and increasing temperatures, across an expanse of irrigated lands where water from the Upper Colorado, as from the western slopes of the Sierra Nevada, are funneled to cities, farms, and irrigation projects, and used to generate electricity. Even as Californians and westerners face the threat of further fires more destructive than any in recorded history–potentially enough to energize an implausible recall effort in the state of California–we face the problems of managing not only historic drought, mandated energy shortages, reduced water supplies. The climate crisis appears to have provoked a deep crisis in leadership, but one without easy means of resolution.

The most improbable political candidates–global warming skeptics after Donald Trump’s heart–have argued drought, wildfire, and electrical storms reveal Gavin Newsom’s lack of leadership, even as they stridently object to aggressive climate legislation aimed at emissions reduction as restraining the free market business,– preferring a free market approach for all climes that would be the laissez-faire redistribution of water to the highest bidder, monetizing a scarce resource to consolidate financial profits and gain in response to diminished water supplies.

As more water is being released from Upper Basin reservoirs to make up for the shortfall in Lake Powell, but the shortage of water in Lake Mead–the largest reservoir in the United States–to less than 40% capacity by 2022 will mean reducing water for lower basin states like Arizona of 812,000 acre-feet, Nevada–by 21,000 acre feet, and Mexico, by 80,000, that have led to the call for new “water markets” to be created across the western states. Indeed, even western states no longer carry the brunt of increased use of freshwater for irrigation–

High Country News

–the demand for conserving water in agriculture is increasingly incumbent on western states, so much so that the shift to less water-intensive crops–like California’s almonds–at a time when many crops require more irrigation, and a shift toward fewer acres of pasturage for livestock–good luck–have become a necessity. Increasing the efficiency of irrigation systems is necessary–ending customs of flooding fields, increasing drip irrigation, center-pivot irrigation, or micro-irrigation, in a New Deal for agriculture, even regulating irrigation systems before water markets price rural communities out of their accustomed access to freshwater. The increased trend toward shifting the distribution of water by “water markets” from lower- to higher-value use is dangerous for farmers, and indeed all rural areas, but also for the western ecology, as it would be the most difficult to preserve water in rural communities or farming areas less able to pay for pricing of water for higher use-value, although they currently consume over 70% of the water in the Colorado basin, or encourage sustainability in regions that are increasingly facing realities of sustained drought, if not megadrought of unprecedented intensity.

United Stated Drought Monitor for Western States, October 2021

Yet the systems of allocating water from the Colorado River by a system of dams, diversions, and canals have led to broad calls to end further projects of water diversion, as the diversion of water to western states may be drying up itself by up leads to calls for new policies of allocating water, not based on the highest bidder, as the river we have made increasingly mobile across boundaries will be divided or redivided between agriculture, urban use, indigenous Americans, and land trusts, as we are in need of redefining the working basis for conserving the redistribution of water rights beyond capture and diversion, and outside of existing water markets and appropriative water rights within states. While the Bureau of Land Reclamation has run the reservoirs, dams, canals, and hydroelectric plants and contracting with individual districts, a broad reconception of practices of regulating water markets, allocations of water, and costs of large-scale water diversion, as demand for water outstrips supply.

Yet as increased farmers are withdrawing water from the ground, or from rivers, from California’s Central Valley to the Lower Colorado River Basin, in Arizona, New Mexico, and Nevada, the need to reduce the eighty percent of water dedicated to agriculture across the west will demand new practices of conservation, beyond what John Wesley Powell mapped, in 1880, when he advocated new practices of land use, as climate change increasingly destabilizes the Basin, including the thirty sovereign Native American tribes along the river basin. The need to manage demand and riverflow that will begin with the start of the “Tier One Shortage” from 2022, will introduce new rules on water-use and supply that stand to reduce the amount of water flowing to Arizona by a third. Water diversion from the Colorado River has transformed the land west of the hundredth meridian by re-engineering its flow to make the “desert bloom.” Yet the recent dramatic reduction of rainfall, river flow, and increased aridity of the lands, leave us contemplating the viability of relying on water diversion.

John Wesley Powell, “Arid Region of the United States, showing Drainage Zones” (1880)

The new arid region is reflected in weather maps, but will be a region of radically reduced piped water and a new landscape of hydrologic diversion. If the “Arid Region” was mapped in earth-tones of clear distinction as a cautionary way by explorer and geologist John Wesley Powell, to alert the government to the distinct climate of lands west of the hundredth meridian, the recent area is both based on more detailed and specific remote sensing records, often from satellite observation, but suggests a far more complex area to manage.

For the western states are linked, both by projects of water diversion, and by hydropower, to a region where rainfall and snowpack has declined, and far less water enters into the river-flow of the rivers whose diversion allowed the expansion of agriculture and livestock across the western states. Due to global warming, the earlier “arid region” expanded, returning bigger and better than ever since it was described as extending west from the hundredth meridian by John Wesley Powell, in one of the foundational maps of climate aridity. In today’s parched California, dangerously low levels of rainfall across the central valley seem to belong to the Arid Region. But we have hardly come to terms with its new expanse or migrating edges. The “lands of the ‘Arid Region'” that Powell had hand-colored with earth-tones to communicate the dramatically falling rainfall west of the hundredth meridian long ago mapped a biting response to the eagerness of homesteaders to Go West, cautioning about constraints on water-rights that division by states–rather than drainage districts–would bring. If current rainfall maps of USDA or EPA seem to engage in dialogue with Powell’s old polemical cry, the limited traction of mapping policy against increased pressures of climate change place most maps in a sort of Scylla and Charybdis, located not in the Straits of Messina, but the scissors of decreased rainfall, rising temperatures, and lack of groundwater retention.

1. The problems of managing water rights and ensuring flow are now far greater than what Powell’s creative palette of before the fact overlays even imaged was able to depict, and was a puzzle beyond the interlocking pieces of drainage districts that he–as if akin to the first puzzle-boards composed of hand-painted maps, as this forty-nine piece puzzle map of ca. 1849, painted by Kelly & Levin, of the similar region, that curiously compressed the western United States. Was Powell’s map indicative of the difficulty of solving the puzzle of allocating water resources across arid western states?

Puzzle “Map of California, Mexico, Texas and the United States,” ca. 1849, Kelly & Levin. Boston MA

While the puzzle pieces rarely echoed the shapes of individual states, undoubtedly because o the difficulty of their cutting the contours of states, the puzzling of how the rivers of the west would align with states in this roughly contemporary 1880 Milton Bradley map-puzzle, an “Outline Map of the United States,” posed by including light blue rivers across a map with little sense of varied topography.

ca. 1860, M. H. Traubel, Lith., Philadelphia PA/American Antiquarian Society

In contrast to the resolution of assembling individual pieces of a map of fixed bounds, the expanded arid region mapped by remote sensing spans a farther territory and expanse, and raises deep questions of access to water or even soil moisture in a region that developed as an agricultural breadbasket and locus of husbandry of livestock.

The growing puzzle broached by how the water supply of the west will be reassigned is rarely faced or addressed, although it is ruminated upon as the sub-text–or super-text?–of terrifying maps of rising aridity and low rainfall across the western states, that magnify a new “arid region” with less clear suggestion of an outcome of land management but pause before the cyclically compounded effects of rising heat, low soil moisture, limited run-off, and the specter of drastic irrigation cuts.

Current remotely sensed maps use far less clearly set boundaries or edges of water-shortages, but pose similarly pressing puzzles of how to resolve the appropriative logic of water rights, as drought intensity reduces the water that once flowed from the “upper basin” of the Colorado, feeding the river and redistributed water, and even more surface water is lost to evaporation.

Snow drought is worsening the American West's water woes | The Economist

The puzzle of hydrological access to land-water has become so curtailed across western states, that increased pumping of groundwater risking depleting aquifers by draining vital aquifers, irreparably damaging rivers and riverine waters. The New Arid Region, afflicted by far more aridity and low soil moisture than at any time, parallel to increased global suffering of warming and increased heat, the persistence of private water “rights” to agrarian expanse stand increasingly on a collision course with global warming throughout the new arid West in ways we have yet to address, even as we recognize that we are facing a climate emergency of the sort without precedent in modern memory.

2. No single visualization can, perhaps, adequately come to terms with the unprecedented aridity of the recent years. For no visualization can fully capture the cascading and magnified effects of declining water and soil health, and their effects on ecosystems, as much as on livestock or irrigated crops: the distance from reduced irrigation and new climate specters demands an intensified map. But the terrifying nature of the intense aridity of western states in part lies in how we have seem to forgot the semi-arid nature of the region. The deeper effects of a drying out atmosphere were evident in the huge deficit in water vapor in the past decade during the “fire season” from August to September, dramatically unlike how fire fighters navigated the same terrain in previous decades, when many fire containment strategies were developed and many active firefighters had trained. The map is one that should raise immediate fears of the loss of a landscape of future irrigation, and the need for tightening agricultural belts and shifting our conceptions of food supply and water budgets–as well as the same landscape’s increased combustability and inability to manage or control by an old playbook.

Decreased Water Vapor Present in the Air in Past Decade from Two to Three Decades Previous

The previous month has brought an even more pronounced record of drought across the Upper Basin of the Colorado on which so much hydropower relies, as do other schemes of water diversion.

US Drought Monitor for Colorado River Basin, September 23 2021/Brad Rippey, USDA

The revelation of a new intensity of exceptional drought in many pockets of the Upper Basin of the Colorado River presses the bounds of how we imagine dryness, aridity, and their consequences, even as we rely on older methods of fire-fighting, and fire-prevention, and outdated models of water diversion and energy resources.

The historical denial of what John Wesley Powell had already called the “Arid Region” west of the hundredth meridian, has become a snare for ecological disaster translating into a process of the drying out of long-irrigated zones, with consequences that the nation has not been able to comprehend–and demand a New Deal of their own to replace the diversion of water and generation of energy in the Hoover Dam. Or have we forgotten the intensity of a differential of climate, soil moisture, and increased aridity that Powell long ago mapped in order to illustrate the new regime of government its unique atmospheric conditions it would require, using his uniquely designed palette to hint at the best way to organize the region of water scarcity according to the units that its drainage districts–rather than the state lines surveyed by latitude and longitude?

John Wesley Powell, “Arid Region of the United States, Showing Drainage Districts” (1890)

Powell had explored the canyons, rivers, and plains, as he addressed the Senate Select Committee on the Reclamation of Arid Lands in 1890, he crafted an eloquent seven-color map of rich earth-tones to impress readers with the sensitivity of the region’s texture and urge restraint for expanding the westward flow of homesteaders with hopes to make the desert bloom. Indeed, by circumscribing areas for which sufficient water in this “Arid Region” would be able to providently allow future settlement, Powell neatly divided areas for settlement in a region by hydrographic basins collecting sufficient rainfall for farming. Whereas rainfall maps of previous years mapped a blank spot of water scarcity, Powell hoped to direct attention by a devising a map of the region’s subdivisions that called attention to its soil quality and decreased moisture, focussing on its distinctly variegated terrain in ways foreign to Senators in Washington. Powell hoped to convince who were removed from the region to acknowledge the commanding constraints created by these drainage districts for all future agricultural development and settlement–an unpopular position that ran against the notion of allocating free land in an age of expansive homesteading. If the image of a “drainage district” was foreign to existing state lines, Powell’s image of an “arid region” long haunted the geography of the American West–and contributed in no small part to the subsequent reengineering of the waters of the Colorado River.

In light of the dramatically increased aridity now endemic to the western states, Powell’s map gains terrifying relevance as western states enter severe drought, placing the breaks on once-expanding developments across western states. Powell’s map articulated a historical vision of the limited infrastructure of water in the American west. While the technologies of irrigation that allowed such a massive project of damming and canalization only later developed, did his map inspire the need for a project of such scale as a better model of land management? The intensified aridity that afflicts the western states responds not only to low levels of rainfall. We continue to hope groundwater depletion that afflicts the lower basin won’t extend to the Upper Basin of the Colorado River that has captured water on which so many farmers rely–and thirty-five million north of the border and three million living in Mexico depend, across its Lower Basin. The escalating megadrought has created pressures across the overpopulated west that the water-sharing model Powell proposed for drainage districts cannot resolve, but the distinct forms of water management he advocated have been forgotten, as the declining water level on the Colorado River seems a time bomb as its waters have fallen so far below capacity that while the waters that drain from the Upper Colorado into Lake Meade, the largest reservoir in the west, have left it only 37% full, and Lake Powell stands at 34% of its total capacity. As less and less water enters the river system of a drying-out west, the future of the river on which so many rely for irrigation and energy is all but uncertain.

The water-level of Lake Mead, the largest reservoir in the US and a critical source of water for millions across the Southwest, has fallen 140 feet since 2000, a third of capacity.  Can we come to terms with the increased aridity across the west that the drying out of the Colorado River may bring?   The western states are haunted by the return of the "Arid Region" John Wesley Powell once mapped.
Lake Meade, May 2021

Demand for water in the upper basin and older technologies have meant far less water reaches the lower basin, but what does has been redistributed across western states–absolutely none reaches the ocean at the river’s old delta. Supplies of surface water and groundwater barely provide for the border region, as the overdraft of the basin’s aquifers have made trans-border water management a crisis often overlooked in favor of water management north of the border. As unprecedented soil aridity currently seems to run off the rails, after three summers of no rainfall have depleted soil moisture, may remind us how we have missed the lesson of Powell’s map of instilling new set attitudes toward the land, as the volume of riverflow consistently dropped as it crosses the Mexico border since the filling of the Glen Canyon Dam.

Does selective amnesia underlie how we map the drying out of the west? Most data vis of rising temperatures and low rainfall across the western states is already magnifying and escalating the effects of unprecedented heat over twenty years in a deeply melancholic vein, daunted by the scale of dryness across such an interstate expanse, and passive before an absence of atmospheric moisture that seems a modern casualty of global over-heating. If we were already “living in the future” in California’s frequent and increasingly extreme fire regimes, the multi-hued data visualizations electrify the landscape–and not with power or hydro-energy, but by the all-too familiar color ramp of the extremes of climate change we have been trying hard not to normalize. These images chart a landscape that has gotten away from us, outside seasonality changes, making the American West a cautionary case study for global climate change inspires melancholy.

The additive logic and graphic syntax of maps, long before the separate map-“layers” that accommodate information from GPS, provided a basis to define the fungibility of water and the emergence of “rights” to water across the Arid Region, enabling the idea of governing the transference of water and water “rights” across the region, that separated water from the landscape and environment. The flow of water had long been understood and reconstrued in the west by a logic of irrigation needs–and the “rights” to unpolluted water for livestock raising, pasturage, and agricultural needs of land owners–that was removed from conserving groundwater needs. The increased nature of the fungibility of water as able to be transacted across basins, state lines, and counties reflects the legal fiction of considering water as a “good” tied to the needs of property owners, that, long before global warming, had already sanctioned the removing water from the ground.

If we use metaphors rooted in temporality that try to come to scale with the new era of global warming that cut down and perhaps minimize the era of water scarcity. in which we are entering–“heat waves,” for example, that broke records in states from Washington to Idaho in June and July, breaking or matching records of hot temperatures, the levels of aridity that have allowed the ground to grow arid and degrade have not only led to a spate of western wildfires, but have changed the levels of soil moisture over the long term in ways we have difficulty to map in the scale of our weather maps, or even the maps of the U.S. Drought Monitor, as the cascading influence of such unprecedentedly dry conditions–where stresses on river water create extraction of groundwater that stresses aquifers and groundwater supplies–can be scarcely imagined, or confined to the conventions and color ramps of weather maps.

We have struggled for decades to process the cascading effects of waves of unprecedented heat that over time have produced a drying out of soil and reservoirs over the past twenty years, resulting in an expanded and far more destructive fire season and parched lands whose effects we cannot fully come to terms or comprehend, as we have not seen or experienced the extent of dryness of subsoil, soil, and low rainfall which the US Drought Monitor seems to have mapped, as drought expanded not across the entire Pacific Northwest, from Oregon to Idaho, or 86% of Idaho–by the land’s combustibility, impossible to read without premonitions of lost forests–including old growth forests–melancholic fears more than tinged by an acute sense of a lack of agency.

The sense of struggle with an absence of agency–at the same time as an almost moral urgency–reflects the difficult to process such absence of water as a landscape we have inherited from the rapidly accelerating dynamics of climate change. The history of the increased aridity is all the more poignant as a source of melancholy not only because exceptional drought was the standard before President Trump, and a national emergency before his Presidency. We have failed to register this national emergency with the same immediacy, even as the theater of the border was magnified in disproportionate ways in public discourse on migration. The sense of melancholy is compounded as the map seems haunted, if only tacitly, and perhaps without acknowledgment, by the fact that the head of the USGS in 1890 admonishingly illustrated virtually the same basins now suffering severe and moderate drought as distinguished by semi-aridity–if the current levels are nothing like those faced over a century ago, when the transition of public to private lands. We have recently mapped the substantial threat of increased aridity to the Great Plains–less than a tenth of whose croplands are irrigated–where farmers depend entirely on rainfall to grow soybeans, sunflowers, cotton, and winter wheat, the fear of greater “dry spells” as anthropogenic emissions drive decreasing rainfall and groundwater reserves–a term that tries to convince us they are not permanent–led red flags to be drawn in broad brushstrokes in those states, where extreme and exceptional ‘drought’ .

But climate change has created a new concept of “water stress”–stresses best be pictured not by the isotherms of weather maps, but the watersheds and drainage districts that were the basis of Powell’s revolutionary map, and matching the very region of the Arid Zone where the soil scientist Powell turned viewers’ attention to the crucial index of ground and soil moisture, the true determinant of the future of agrarian settlement and the future of food. The regions determined of greatest future stress were the very basins that Powell mapped, and suggest the relevance of his map, as well as his caution of the difficulties of governance in an area of severe water stress-stress being understood and indexed as a relation between supply and demand, as well as rainfall, in national watersheds.

3. The “Arid Region” of the Untied States had been austerely and admonishingly described by John Wesley Powell as a geologist to caution against the administration of its future settlement with a level of clarity that reveals his Methodist upbringing. It is hard to know how clearly we can ever parse aridity, in an age when rising temperatures have unremittingly drained soil of water. As if informed by a deep respect for the map as a clarity of record, possessing the power to reorient readers to the world by preaching a new relation to the land, Powell had placed a premium on cartographic form as a tool to re-envision local governance–and prepared his striking eight-color map of the limited rainwater that arrives west of the hundredth meridian, the eastern border of what he baptized as the Arid Region, an almost zonal construction akin to a torrid zone.

The imposing title of this reclassification of the interior of the United States revealed Powell’s own keen sense of the map as a visual record of the territory, whose transparency as a record of the quality of the land would be a basis for all discussion of settlement. Powell parlayed his own deep study of the geography of the Colorado Basin to query the value of parsing the administration of water rights by state lines in 1890, convinced of the need to oversee later apportionment outside the jurisdiction of the arbitrary boundaries of western states, but joined them to his sense of duty of preparing a legible map of striking colors to convey the constraints and difficulties for its future settlement– not only by the scarcity of the threads of rivers curled against its topography, but the few watersheds.

Powell trusted the map might mark the opening of the “Great American Desert” in order to alert the US Congress that the dry lands west of the hundredth meridian was a divide. Even if the meridian no longer marking as clear a divide of reduced rainfall, as we confront the growth with unprecedented degree of global warming of a parched west–both in terms of reduced rainfall and declining soil quality–it may serve as a model for the map we need for the future governance and administration of already contested water rights. Powell’s place in the long story of soil quality reflects how neatly the American west as a microcosm of global warming is rooted in the conversion of public lands to private ownership, into which warming has thrown such a significant wrench.

Arid Region of the United States, Showing Drainage Basins (1890)

For the Arid Region’s aridity has since been unremittingly magnified, producing a region more arid than we have ever experienced and struggle to find an adequate color ramp adequate. But we would do well to try to map the forgetfulness of that arid region, even as we confront the quandary of the stubborn continuity of sustained dryness of a megadrought enduring multiple years, compounding the aridity of the soil, and multiplying fire dangers–and the conditions of combustibility of the region–far beyond what the west has ever known or Powell imagined possible. If aridity of soils and poor land quality has spiraled out of control due to “global warming,” raising questions about the future of farms and livestock, the absence of groundwater and surface water alike, global warming demand we shift from national lenses of water shortage to beyond American territory,–but also to discuss the warping nature of national lenses on the remaking of the sediment of the west–and Colorado Basin.

The difficulties of parsing river-flow by “states” as helpful political aggregations for future settlement was rebutted by the map, which sought to direct attention to the aridity of the ground’s soils to orient its administration in a region where water was destined to remain front and center on settlers’ and residents minds for the foreseeable future. The subsequent attempt to jerry-rig the question of scarcity of water by entitlements that rely on re-apportioning unused water escaped the constraints Powell located in the basic common denominator of groundwater.

As much as the region needs to be mapped outside a national context–despite the national nature of climate tracking–the hope of revealing imbalances of the drought indeed exist across borders, and impact water-sharing agreements, much as the smoke from recent northwest fires has traveled across the Pacific northwest. National territory is as meaningless an analytic category for global warming, or water scarcity, which, this blogpost argues, exists in a global contest of migration, as the migration or transborder transit of fires’ smoke.

4. The conditions of aridity that Powell described in the Colorado Basin and its neighbors offer an oddly productive image of the dryness of the ground, in an era before irrigation, that may be useful for how we can come to terms with the fear of a suspension of irrigation across western states. But it is as if the very definition of aridity was forgotten, as infrastructures of irrigation have re-mapped the region that John Wesley Powell in 1890 mapped as an area of difficult agrarian settlement, as farmlands of agrarian fertility and wealth. Powell proposed to view the “arid region” of the United States east of the Rockies with a clarity approaching scripture in a powerful eight-color map to instructively show how limited water constrained settlement of the region after surveying the Colorado Basin.

Powell probably imagined his map in somewhat revisionary as much as rebarbative, reorienting attention to the dry nature of the soil of the semi-arid region of the Colorado Basin by parsing it in areas by which the availability of water constrainted the settlement of the “open” government lands of the west, obscuring that they were seized from indigenous, to correct the mythic geography propounded by official state-sponsored geologists. Unlike Powell, most state geologists had boosterishly endorsed a site for future pasturage, to be enriched by unknown artesian springs, and ripe for settlement by homesteaders, and Powell’s map posed a more tempered image of resettlement that would obey the laws of the availability of water in the Colorado plateaux and other regions he knew so well, cautioning against the encouragement of settlement and sale to prospective farmers in ways that have improbably made the map something of an icon of conservationist thought. Against promise of prospective bucolic lands of pasture, the dry colors chasten viewers by communicating scarcity of water of drainage basins.

The arid region that Powell correctively propounded was long inscribed in the psycho-geography of the United States to be forgotten, but the arrival of irrigation infrastructure allowing irrigation of western states continues to inform, even in our own era of global warming, the return of the boosterist sloganwhere water flows, food grows,” that is still raised in Northern California’s San Joaquin Valley, to protest “cuts to farmwater” in the recent order of an “emergency curtailment” across rivers of the Sacramento-San Joaquin Delta watershed — essentially the entire Central Valley. The recourse to an engineering “miracle” of making water flow uphill and redistributing more water from reservoirs contest calls for conservation–and only demand the further construction of dams, reservoirs, and water storage for better irrigation. The very promises that the flow of the Colorado River would irrigate lands, that made good on the promises made to homesteaders by describing the region to settlers as a New Canaan, where the growth of future streamflow and even rainfall that had never been documented, would make it suitable for the expansion of animal pasturing and farming, suggests a mythic geography of timeless bounty has replaced its actual conditions.

Friant-Kern Canal Flowing past Kern Dam/Septmeber 2020, Eric Paul Zamora, Fresno Bee

The mythic geography led to a rewriting of America’s irrigation infrastructure that in itself may be one of those pieces of infrastructure just no longer adaptable to extreme climate change. And as we face the scale of the national emergency of water shortages about to be triggered by falling reservoir levels, the crisis of using and recycling water, and the inefficiency of desalination plants of riverwater and groundwater, on which the world currently relies–and were predicted by the US Bureau of Reclamation back in 2003 to provide a “sustainable” solution to the dwindling water provided by the Colorado River, which had allowed the unexpected expansion of the settlement of western states. While desalination plants currently generate worldwide over 3.5 billion gallons daily, with 50 million gallons produced daily in Carlsbad, CA alone, desalination plants in one hundred and twenty counties, only half using sea-water, its energy expense justified as Colorado River decreased, promoted as a “sustainable and drought-proof water supply in Southern California” in an era of climate change, as if to calm our concerns at the dramatically decreased groundwater of western states.

Reclamation scientists assured the nation in 2016 of future recharge in the Upper Colorado Basin would offset temperature increases in their modeling scenarios through 2099, projecting basin-wide precipitation, the fears of the persistence of a mega-drought of extreme aridity with little recharge that may last decades has left fifty-sevens million living in drought conditions across the west according to the U.S. Drought Monitor, that has brought a new era of mega-fires. The thin blue line of the Colorado River is but a crack or thread coursing through a combustible landscape in this recent map of the expansion of unprecedented extreme drought in western states from National Geographic:

For all the disturbing and disquieting elegant if terrifying spread of deep red isotherms in Riley D. Champine’s map, the consequences of such exceptionally below-average levels of precipitation and aridity are difficult to comprehend as cumulative and deep in our nation’s history, as well as the effect of man-made climate change.

The utter saturation of this data vis of growing dryness of a region where rain far below previous norms fell forces the viewer to process an undue range of measures of aridity that they must struggle to process-if the deep orange and reds approaching emergency warning to suggest that surely a climate emergency is at hand. The absence of text in the visualization invites viewers to acknowledge they stand an eery remove of familiarity with an irrevocably landscape, posing unspoken if also unanswered questions about hydrological infrastructure in the Colorado basin, and greater west, that all but erases the geopolitical formation of this landscape–interruption of a rich color ramp at the southwestern border compartmentalize the large-scale decline in precipitation apart from national categories; but the danger lies in its focus on the economically developed north, more than the global south, as if it lacked adequate resources to prudently respond to groundwater shortages, but as an emergency for the developed world.

The focus of the climate emergency is on a large scale, daunting the possibility of individual response, but focussing on prudence at a local level, even if its scale is not defined, questions whether state politics can even resolve the intensity of the dilemma of declining rainfall levels below a thirty-year norm, a deviation on so broad a scale to be impossible to process save in local terms, but that omits the way the basin has been engineered as a site where groundwater now all but fails to accumulate, increasing the basin’s deep aridity more than the color ramp reveals.

The trust that Powell placed in his maps stand in sharp contrast to the “purple” coloration of regions of extreme heat introduced across western states to suggest so many “red-flag” warnings of excessive heat. In a year already tied with 2017 for receiving “excessive heat” warnings from the National Weather Service, already in early summer at a rate that is increasingly alarming, purple designates the need for caution when leaving air-conditioned environments, and suggests the booming of electric cooling across the west: the metric of a prediction of temperatures reaching 105°F for a two-hour stretch has paralleled the debate in Washington on infrastructure spending that suggest a similar disconnect that Powell confronted when he tried to describe the need for constraints on planning settlement west of the hundredth meridian in 1890.

Four Excessive Heat Warnings issued from late May 2021 have introduced yet a new color to prominence in National Weather Service maps, the new deep purple was introduced in weather maps in 1997 as a venture of the NWS into health alerts; rarely used in other weather maps, which in recent years have shifted from urban areas to large stretches of the nation, shifting from a use of red to designate high temperatures to purple to designate risk of triple-digit temperatures, especially in man-made surfaces like asphalt (able to rise to 170°-180° Fahrenheit–territory of third-degree burns–or cars which can rise thirty degrees above air temperature.

Heat Advisories, July 11, 2021/National Weather Service

During the decade before 2003, the water-level of Lake Mead had begun to decline precipitously, inaugurating a historical decline that led it to fall to but 35% of its storage abilities. While the decline was not more precipitous than the two earlier declines in its water-levels in the reservoir from the mid-1950’s and mid-1960’s, the current decline in storage capacity of what is the largest reservoir of water in the United States has raised the unthinkable and unimaginable arrival of water cutbacks, as Arizona’s share of the Colorado River’s waters will be reduced by 7%, and Mexico–where the Colorado runs–will lose 5% of its share, in a scenario never foreseen in the dam’s history, but that reflects the increased aridity of the watershed from which the Colorado River draws. The decline to 1,075 feet in the reservoir’s depth that triggered the Tier 1 reductions in flow may only be a harbinger of the arrival of future Tier 2 reductions, should Lake Mead drop to 1,065 feet, as is expected in 2023, and raises the fear of a Tear 3 reduction, should the lake level fall below 1,025 feet, reducing the water allocated to western cities. In ways that the infrastructure of irrigating the Arid District of the United States could never have foreseen, the arrival of the driest period that the basin has ever experienced in 1200 years has brought longer periods of drier weather without rainfall that have reduced the riverwater that fills the reservoir.

The declining level of Lake Mead plunged below average lake elevation of 1173 feet, by 2003, in ways that should have sent alarms across the west, were we not consumed by a war against terror. The Bush administration’s attacks on global warming grew, questioning the science of global warming and the dangers of increasing aridity. But the disconnect between the expectation for irrigation by the farming industry and farming states was dismissed, with global warming and climate change, as temporary shifts that wouldn’t alter the landscape of irrigation or river flow.

Robert Simmon, based on data provided by the U.S. Bureau of Reclamation

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Mapping Water’s Presence and Absence Across Land: Maps of Aridity and Drought

Maps can potentially provide quite supple tools to draw the distribution of a variations among land and water, and to reflect on the local variations of the specific landscapes they represent.  Yet the conventional of land-mapping do not clearly lend themselves to describe the presence of water in the land–and all too often presume a clear boundary between land and sea, a fiction known as the coast, one of the clearest inventions of cartographers.  We struggle to describe the relation between land and water–whether in our imagery of drought, which has become particularly popular with increasing evidence of climate change and global warming, or in describing the levels of groundwater loss across the land.  Hence, even as we confront the potential collapse of aquifers, and a rapidly shrinking supply of underground water, we don’t have a clear iconography of how to render the very dilemma–even if the problem of groundwater depletion stands to only increase.

The recent findings of such deletion of groundwater sources in much of the United States since 1900 is big news, but the means to illustrate the rates of its increasing disappearance–or indeed the potential losses that such groundwater losses imply in much of the country–pose problems of cartographical rendering, as much as environmental catastrophe:  the two seem far more closely intertwined than has been argued.  Take, for example, a recent and particularly valuable USGS study of the levels of groundwater depletion that historically increasing removal of subsurface groundwater from the lower forty-eight states, in terms of a combination of levels of subsidence, drainage, and water-flow, that mirrors the central regions of agricultural production and farming in the United States since 1900, but which primarily depends on modeling aquifers’ depletion:

Groundwater Depletion, 1900-2008

Groundwater Depletion, cubic km

USGS:  Leonard Konikow, “Groundwater Depletion in the United States (1900–2008)” 

We are similarly deeply challenged, in representing the drama of increasing drought.

The syntax of terrestrial mapping does not lend itself easily to the mapping of drought, or indeed to mapping the presence and absence of water in our worlds, or the role that water plays in the landscape.  For the very mobility and fluidity of water across environments is, as the current drought has revealed, not easily able to be naturalized into the landscape, or fixed in a map, and the interaction of water with our agrarian and rural landscapes in face difficult to map.  Cartographers all too often rely only on ruled lines to organize land maps, and the syntax that was developed to draw divisions and preserve boundary lines, and indeed bound territories and nations have the disadvantage of instantiating divisions as if they were natural, and part of the landscape that we see.

Rather than bounding the regions of land and water by sharp lines as if to differentiate them, web-based maps that sense degrees of the relative presence of water provide a new and almost dynamic format to frame questions that depend on visualizing the presence of water on which even landlocked regions depend.

The map brings into being new entities to visible form that we could not otherwise see in a material form, and allow us to better contemplate and reflect upon the different sort of water-levels on which the fertility and richness, but even the usability, of land depends.  The two-fold qualities of how the map brings things into existence and offer tools to think exist as two sides of the same sheet of paper, both present in how we inscribe space in a map as a way to  view space in the definition of their contents.  Whereas informative content lies inscribed according to indices on the map’s surface, maps also project meanings lying beneath:  on their obverse lies their take-away value, or the picture of the world that they shape in our minds. The symbolic conventions of maps are to be judged both by the accuracy of their design and their communicative value.  But while lines are useful tools to define and bound territorial space for viewers, they are far more limited as tools to describe the presence of water in the land, much as notoriously neglect or efface the areas where land and water interact, or the fluctuation of the boundaries between land and sea, and even harder to map the absence of water in the land–either in terms of its severity or the gradations that can be drawn in conditions of drought.

Despite the compelling nature of our mapping of the California drought–and the prospect of regions sensitive to increasing water stressors and drought worldwide–maps of drought raises compelling questions the conventions of its mapping and the take-away of maps of drought and aridity.  And the picture that emerges of the recent three-year California drought in one’s mind seems of utmost important to its understanding:  one can think of the hugely valuable perspective that Michael Bostock has recently compiled, using data from the National Climatic Data Center, charting regional climactic variations in drought across the United States since 1880–in addition to a more qualitatively detailed set of visualizations of the drought’s local effect on specific crops–with truly dizzying results. How to best orient readers to the shifting boundaries and relatively recent advances of drought in the American West, without falling into dangers of historical relativism?  How to both appreciate the current drought’s significance and present it to readers?

We’ve perhaps only begun to consider drought as a mapped concept, but the complex interaction between aquifers, land-water, snowfall, rainfall, and ambient temperature due to global warming–all difficult enough to visualize on their own, let alone in relation to each other–are particularly difficult to map in a cogent but dynamic form.  Does the most recent map of the Drought Monitor, authored by Richard Tinker for the USDA, disarm viewers by a heat map to show basic gradations of drought across the entire state–where black designates exceptional drought (“D4”), and red extreme drought (“D3”), mapping the reach of parched land as terrestrial expanse.  But despite its impressive impact, is this image a communicator of the scope of drought or its effects, even as it charts relative aridity across California’s counties?  This both invites reflection on the economic future of the region’s farms , but threatens to naturalize the very subject that it also maps.

January 21, 2014

Although we demand to be able to use the syntax of the line in maps to define territories, a similar syntax is less able to be borrowed to map water or map drought. Indeed, the lines that are present in the above drought map to shade regions to acknowledge drought severity are hard to reconcile with the same lines that bound the  state, or that divide its counties, since they are of course less sharply indicated by a line, or approximated by the broad classifications used in a heat-map, whose lines are more porous and approximate as much as definitive–and overly suggestive of clear boundary lines.  This is more clear in some of the interactive drought maps that ostensibly image drought conditions in and around the Central Valley, a center of produce and agriculture, here oddly superimposed on a Google Earth satellite view:

SF and Central Valley by Satellite View

Drought can be mapped, at the same website of interactive drought conditions, as distinguishing drought severity superimposed as filters on a base map of the state of Google Earth provenance, to divide red “severe drought” in the north coast and the “extreme drought” in the northeast interior basin of the state:

California Interactive Drougth Conditions

Sure, the subjects of states and drought are apples and oranges:  mapping tools don’t lend themselves easily to such a data visualization, both by drawing false equivalents and distracting from the nature of drought and the mapping of its momentous effects–if not offering an instantiation the condition of drought as if a fait accompli and natural event–rather than one that emerged because of the uniquely opportune mechanisms of water redistribution in the state that have left it so open and vulnerable to the drought’s occurrence.

If paleoclimatologists doubt that a drought of comparable severity has not only not existed in the recorded history of rainfall in California of the past one hundred and sixty-three years, but past ‘megadroughts’ from 850 to 1090 AD and from 1140 AD to 1320, and has already been drier than any time in the past 434 years, due to the perfect storm of water diversion and agricultural intensification.  And the lack of a clear map of drought leave us without any clear sense how long the drought will last, and no sense of how urban demand for–and ability to pay for–water will be resolved with a limited supply.

We’re not used to or well-equipped mapping oceans or bodies of water that overlap with lands.  Even when we include oceans in land maps to define their edges or describe their coasts, the syntax of much mapping of territories ends at the water’s front.  And much as we need new modes to map the interface and exchange of habitats on estuaries or shores, the mapping gradations of moisture or aridity are difficult to inscribe in the surface of the map–even as we demand to map the limits of groundwater and the prospect of draught.  The exclusion of water from most land maps reflects our limited abilities to map and the limitations of liabilities are increasingly evident.

The two spheres needed to be mapped–under and above water–are seen as incommensurate with each other and we map them by lines in different and distinct ways:   we map limits and frontiers by rings or lines, or note fixed routes of travel or topographic elevations by fixed lines, the conventions of the line seems less suited to the blurring of gradations in groundwater, levels of drought, and the levels of water lying in the land–or of the diminution of both rivers and aquifers. And the presence of water in a region, or in the levels of soil and subsoil–and aquifers–that lie beneath the land’s surface, is particularly difficult to map by the syntax of a land map, because its conditions are multiple.

The syntax of the heat map may seem appropriate in its cognitive associations, but is far less supple or sensitive as a map of environmental impact, let alone as a tool to conceive of drought.  Indeed, any “ecotones“–a word coined to direct attention to those regions where bordering ecosystems meet and intersect–are  difficult to map both because they are so difficult to demarcate and because it is difficult to establish a single perspective on the intersection of worlds often assessed by different criteria.  The shoreline, such as, as the meeting place between land and sea, has long been notoriously difficult to map, and not only because of its fluidity.  We map a stable topography, mountains, rivers, and lakes, where the quotient between land and sea is fixed:  and mapping rarely extends out to the surrounding waters, or boundaries of blurred, shifting, or overlapping lines:  a problem of increasing notice in those endangered areas where habitats of land and water overlap and intersect, making clear boundaries less able to be defined.  This is especially true in drought, where we must consider relations between groundwater storage, aquifers, and surface water, and the different sources and flow of water through agrarian and to urban landscapes. This problem of cartographical representation is as pronounced in the mapping of drought.  The  mapping of the absence of water is indeed a particularly apt problem for cartographical design in a heating-up world, as revealed in the maps we use to track, analyze, and understand drought. Bay Area to Modesto and Monterrey Mapping the shifting dryness of the land–and the drying up of resources–presses the conventions of cartographical inscription.  And all too often, we have only mapped land–not water, or even dryness–save in the limits of the desert lands.  And the two sides of mapping the presence or absence of water offer complementary images, in ways that might often make it difficult to assess or chart the meanings and impact that the drying out of regions and habitats might have–or, indeed, to “embody” the meaning of or spread of drought and dryness in a legible manner.  What would it mean to make drought a part of mapping that would be readable?  How, in other words, to give legibility to what it means to subtract water from the environment? Indeed, we demand a dynamic form of mapping over time that charts the qualitative shifts in their presence in the land.

Whereas resources like water have been long assumed to be abundant and not in need of mapping in space, as they were taken to be part of the land, the increasing disappearance of water from regions like much of California–the first subject of this post–raise challenges both of conceiving drought as a condition by embodying the phenomenon, and by using graphic conventions to trace levels of water in the ground.  In the case of the recent California drought, the compounded effects of an absence of winter rains, which would normally provide the groundwater for many plants throughout the year, feeding rivers and more importantly serving to replenish  groundwater basins, but has decreased for the past three years at the same time that the snowfalls over the Sierra Nevada, whose melting provides much of the state with running water–and on which the Owens Valley and Southern California depend–have also dried up, leading to a decrease in the snowpack of a shockingly huge 80%.  At the same time as both these sources of water have declined, the drying up of the Colorado River, on whose water much of the western US depend, have curtailed the availability of another source of water on which it has long depended.   How to map the effects and ramifications of historical drought levels or impending dryness over time that synthesize data in the most meaningful ways?

These are questions both of cartographical design, and of transferring data about the relative presence of water in the land to a dynamically legible form, at the same time as retaining its shock content.  The pressing need to map the current and impending lack of water in the world raise these questions about how to map the growing threat of an expanding drought and the implications that drought has on our land-use.  The question with deep ramifications about its inhabitation and inhabitability, but not a question whose multiple variables lead themselves to be easily mapped in a static graphic form.  And yet, the impact of drought on a region–as Thomas Friedman has got around to observing in the case of Syria, both in regard to the failure of the government to respond to drought that devastated the agricultural sector and that swelled cities in a veritable ecological disaster zone–offers a subject that threatens to shake the local economy.   And what will animals–both grazing animals and local wildlife alike, including salmon–make of the lack of river water, much coming from the Sierra Nevada, or the residents of the multiple regional delta across the state? Friedman’s analysis may seek to translate the political divisions in Syria into the scissors of the Annales school–he advocates the importance that dedicating funds to disaster relief have already been proven to be central in foreign relations as well as in a region’s political instability, as if to table the question of the content of a political struggle.  But the impact of rising aridity on agricultural societies is perhaps not so much lesser than its impact on agricultural industry.

Rather than offer metrics to indicate social unrest–although political consequences will surely ensue–the rise of water maps show shifting patterns that will probably be reflected most in a tremendous growth of legal questions about the nature of “water-use rights,” however, and the possible restriction or curtailing of a commodity often viewed as ever-plentiful and entirely available for personal use, as well as a potential shift in food prices, eating habits, and a dramatic decrease–at least potentially–in access to freshly grown food across much of the United States, if not the sort of massive out-migration from rural areas that occurred in Syria. Michael Bostock’s current mapping of drought’s local effect on specific crops provides a compelling record of the complex questions that mapping the data about the presence of water in the land might be able to resolve.  For the main source of much produce in the US, with the California drought, seem drying up, if we consider dry America’s considerable heavily subsidized acreage of agricultural production.

CaliforniaCommodity Agriculture urban design lab

But we are in the very early stages of making clear the legibility of a map of dryness and draught, or of doing so to communicate the consequences of its effects. The interest in mapping our planet’s dryness is a compelling problem of environmental policy, but of cartographical practice.  Maps of drought and dryness are often econometric projections, related as they are to interlaced systems of agricultural production, resources, and prices of food costs, and based on estimates or climactic measures. But they are powerful tools to bring dryness into our consciousness in new ways–ways that have not often been mapped–or integrated within maps of drought’s local effect on specific national crops.  Perhaps the familiarity with understanding our climate through weather maps has created or diffused a new understanding of climactic changes, forming, as they do, visual surrogates by which to understand complex and potentially irresolvable topics into inevitable complex public debates, and indeed understand our shifting place in the world’s changing environment.

The recent severity of the current California drought–the greatest in measured history, and actually extending far into much of the West– and the parallel drought in the central United States creates a unique mapping of drought severity across a broad swathe of the country that raises problems not only in our agricultural prices, but in much of the almonds, lettuce, and strawberries that derive from California.  The drought is not limited to the confines of the state, although the intense reliance of California farmers on irrigation–some 65% of state crop lands are irrigated, mostly in the Central Valley, where they depend on the viaducts to carry water from the Sierra’s snowfall to farmlands–makes it stand out in a map of the drought’s severity.  (One might return here to Bostock’s powerful visualization of drought’s local effect on specific crops.)

The map of the absence of water in these regions is, however, difficult to get one’s mind around as if it were a property or an accurate map of a territory:  the measurement of its severity is indeed difficult to understand only as a status quo of current meteorological events, for it poses the potential triggers for never before seen changes in agricultural markets and lifestyle.  How can one map the effects of what seems to be the driest in perhaps 434 years, as UC Berkeley paleoclimatologist Lynn Ingram has argued? Both raise the specter of global warming more concretely than we have seen, but are oddly difficult to place into public discussion outside the purely local terms in which they are long conceived:  the drought is not only the problem of Governor Jerry Brown, perhaps personally haunted by the drought of 1977, but the news stories on the issue–as one from which this map was reproduced used in the New York Times to illustrate the drought’s scope, and to hint at the severity of its consequences as much as the expanse of the drought itself, that combines all three aforementioned sites of drought–the Sierra Nevada snowfall; winter rains; Colorado river–in one powerful graphic that reveals the effects of drought on the entire western United States, as if it was a fixed or invading miasma, the vectors of whose spread are less known: ‘ Drought Severity--California

Max Whittaker’s quite eery photograph captures the resurfacing of an abandoned ghost town in Folsom Lake, now suddenly able to be seen with declining water levels of a marina now at a mere 17% capacity, is a striking image of water’s absence in one specific region of the state:

DROUGHT-master675Max Whittaker/NY Times

Other lakes on which much of the southern half of the state depends, like Owens Lake, have shrunk to a visible extent:


How can we adequately map this shift in liquid resources?  To make the graphic palpable, an animated stop-action map of dryness–both historical and projected–could express a useful and compelling record of the mechanics of draught and global drying out might illuminate a perspective on the shifting relation to water we are condemned to live with.

The global shifts in water, from regional water-tables to rainfall to ocean levels, and the mixtures of saline and freshwater they will create, suggests a broader calculus of hydrographic mapping and potable water, the likes of which were never conceived just forty years ago–or, perhaps, just twenty years past.  As a start, such a map might begin from the shifts in a resource like snow, whose absence has caused not only many Californians to cancel trips to Tahoe or to ruin their skis on the slopes, but to face an economic crisis in water’s availability, evident by a comparison of aerial photographs showing the ecosystems of levels snowfall in the Sierra on successive January 13’s just one year apart which reveal dramatically different appearances of identical terrain:

January 13, a year apart

Far more shocking than a map, in many ways, the two images effectively register and embody a shift in how the landscape exists, even if it only implicitly suggests the ecological impact that the absence of that huge snowfall has on its nearby regions:  the absence of green in the adjoining basin, now a dust bowl, suggests a radical transformation in landscape and ecosystem. How can one show the shifting water-table, rainfall level, against the rivers that provide water to the land and its several delta?

A ‘better’ map would help get one’s mind around the dramatically different notion of the usage and circulation of water in and across space–as much as the regions of dryness or low water-levels in the state.  Both NOAA and NASA determined that last year was tied for the fourth place as the warmest year globally since record-keeping began in 1880 with the year 2003:  probably due to increased use of coal, raising the temperature 1.78 degrees Farenheit above the average for the twentieth century, but also creating specific problems in the form of an off-coast high-pressure ridge that has created a barrier that has blocked winter storms, perhaps due to the increased cold in Antarctica on top of the decline in water that descends, melted, from the Sierra’s icepack–leading to an increased reliance on groundwater that will continue for the foreseeable future. The current USGS map of the drought today–January 21, 2014–notes severe conditions of drought in dark brown, and moderate drought conditions in orange, placed above a base-map of dryness across a visible network of riverine paths each and every day: Today's Drougth

Yet the variations of coloration can’t fully communicate the consequences desiccation of the land.  The “moderate” drought in the central valley–surrounded by conditions of severe drought–reflects the limited amount of water brought by aqueducts to the region, rather than a reprieve from national conditions, and roughly correspond to the paths of the California Aqueduct and San Joaquin river:


Perhaps a better model for mapping drought exists, but questions of how best to unify empirical measurements with the availability of water–and the consequences of its absence–are questions for data visualization that have not been fully met.  The ways that USGS maps real-time stream flow in comparison to historical conditions for that day provides a pointillist snapshot of dryness–but using the red to suggest “low” and crimson “much below normal,” as measured in percentile–and yellow “below normal”–the scientificity of the map gives it limited rhetorical power, and limited conceptual power as a basis to assess the expansive effects of drought or extrapolate the critical readings of water across that network in ways easy to visualize.

Streamflow Conditions in CA--Jan 21

The USGS Waterwatch offers an even better metric–if with minimal visual shock–in mapping the areas of severe hydrologic drought in crimson and a new low of drought levels in bright red, in its map of stream flows over a 7-day period, which suggests the range of lows throughout the region’s hydrographic water-stations and across the clear majority of its extensive riverine web, and indeed the relative parching of the land in sensitive regions as the northern coast, Sierra, and parts of the central valley, as well as the rivers around San Francisco and Los Angeles:

New Lows in Riverine Flow

These maps seem to omit or elide human agency on the rapidly changing landscape.  Despite the frequent vaunting of the purity of the water carried from the snows of the Sierra, deep problems with the California water supply–problems caused by its inhabitation and industrial agriculture– become more apparent when one considers the impurity of the groundwater table.  This map, based on domestic wells of water withdrawal, offers a sobering image of what sort of water remains;  although the most southern sector of the state is clearly most dependent on groundwater withdrawals of some 30-80 millions of gallons/day, significant sites of the withdrawn groundwater from within the Central Valley Aquifer, extending just inland from and south of San Francisco, and at select sites on the coast, contain surprisingly high nitrate contamination due to fertilizer runoff or septic tanks–measured against a threshold for having a negative effect on individuals’ health.

Groundwater in State

The closer one looks at the maps of how the state has begun to dry up over time, the further peculiarities seem to emerge of California’s geography and its relation to water–and indeed the sort of water-exchanges of three-card monte that seem to characterize the state–that are to an extend compacted by the dependence of much of coastal California on the extended winter rains that provide enough water for most plants to store.  (The absence of water in much of Northern and Central California now means that the leaves of maples and many other trees are turning bright red, due to their dryness and the bright winter sun, in ways rarely seen.) We might do well to compare some of the other means of tracking drought.  The US Drought Monitor suggests that conditions in current California dry spell differ dramatically from just two years ago–at a time, just two year ago, when Texas seemed a far more likely candidate for ongoing drought.


While the image is not able to be easily accessed in animated form, a contrast to a recent reading of drought from this year reveals the striking expanse of extreme and exceptional drought in California’s Central Valley and much of the entire state, to compare the above to two more recent drought maps:

US Drought Monitor Jan 21

Drought Monitor Jan 28 2014

Yet the concentration on broad scale changes in the regions that it maps offers somewhat limited sensitivity to the variations of water-depth.  The map moreover suggests a somewhat superficial appreciation of the drought’s expanse and the nature of its boundaries.  But the greater sensitivity of satellite readings offers a more multi-leveled–and indeed both a thicker and a deeper reading of underlying factors of the local or regional drought in the American West.  The upgrading of drought–or the degradation of local conditions–in only one week is striking, and effects precisely those regions most sensitive to river irrigation that were effected by the failure of arrival of a melted snowpack, the effects of which seem destined to intensify.

One Week Shift

The twin satellites that measure the distribution of groundwater offer an other point of view of the local variations of drought.  The record of hydrological health, known as the  Gravity Recovery and Climate Experiment, whose paired satellites use two sensors spaced some 220 km apart as a means to detect a shift in the ongoing redistribution of water on the earth’s surface, offering a comprehensive indexing of their remotely-sensed measurements by longitude and latitude.

Satellite NASA

The extracted data is combined with an existing meteorological dataset, in order to create a record sensitive to variations of but one-centimeter in groundwater level.  Although not registering the depletion of aquifers, and primarily climactic in nature, the portrait that emerges from specific shifts in gravity suggested by water’s lower mass effectively track water’s presence with considerable precision on exact coordinates, creating a composite image of national drought that suggest the different variations in the presence of groundwater, by integrating groundwater and soil moisture from surface moisture of their remotely sensed data with actual meteorological changes observed from land and space to create a comprehensive picture of water storage at different levels in the earth.

GRACE mechanics

GRACE has aimed to map the shifts in groundwater levels over time:  the result suggests in surprising ways some relative stability between 1948 and 2009, to generate “a continuous record of soil moisture and groundwater that stretches back to as a way of indexing moisture levels in the soil at different strata.  The striking change in such levels in relation to data of 1948 is an especially striking record of the contrast between just 2012 and 2014.  By creating a map based on the composition of underground water storage as remotely sensed via two satellites orbiting earth, the measurement of ground water retained in the land is a crucially informative record of gradations of aridity, and levels of drought, allowing us to discriminate between ground water and soil moisture–and indeed to understand their relationships in an easily viewable manner, translating satellite measurements into a format easy to compare as a mosaic of local levels of aridity and regional differences that demand to be cross-referenced with agricultural production and across time.

Groundwater Storage 19489-2014

The map of ground-water storage suggests strong contrasts of the relative surplus of waters within the irrigated Central Valley and the relative aridity or dryness of land in much of the Lost Coast in California and deep south.  The “change in perspective” resulting in two years shifts attention to shifts in the amount of groundwater measured, processing data of water stored in the earth that has the potential to analyze the relative irrigation of expanse in easily viewed fashion.

Within just two years, or course, this picture of ground water storage had dramatically and radically changed whose impact we are only beginning to assess, and done so in ways that show no signs of ending.

Ground-Water Storage 1948-20089

To be sure, the wetness percentile of areas near the land of lakes and central United States seems a striking contrast in this image of ground water storage, in this image deriving from the University of Nebraska, which reveals itself to be a particularly rich area of soil storage of groundwater, in, significantly, an area without much surface soil moisture based on Soil Moisture Study.  But the deep pockets of wetness decline by far–both in storage and in soil moisture, based on the draining of aquifers and increased aridity or desertification–present a bleak picture in some strong crop-producing regions of the south and southwest, as much as California–and an even more terrifying story when the moisture of its soil suffer dryness–the excessive aridity specific to California relative to the nation is far more starkly revealed.

Soil Moisture on Surface

The registration of surface soil moisture and groundwater suggests a dynamic tiling of national space that we can use to map wetness over time, and extrapolate the effects of increased aridity on farm-lands and regions that will no doubt shift the prices of water, as well as the costs of agricultural production and livestock.  The mapping of specific water available for root systems across the nation, based on satellite data coded to specific longitudes and latitudes, provides a third level of analysis based on the levels of water available to root systems across the nation–and reveals the even more concentrated effects of drought within the region that depend on water from the California Sierra that will no longer arrive in the Central Valley this year:  more concentrated than the earlier image of ground water storage, that reveals the amount of water available to the root systems presents a picture even more closely related to agricultural constraints created by three years of drought.

Root Zone Moisture

The remote sensing of such levels of moisture and groundwater affords a model of mapping that can be keyed directly to the questions of specific crops in ways that can be eventually used to make prognostics of the impact of drought on the local economy.  If California’s conditions seem to be due to meteorological particularities of low snowfall and few winter rains, held off the shore due to a high pressure ridge of air related to dramatic cooling in Antarctica, the problems that underpin the mapping of the local of integrating layers of data from different sources are repeated.  They reveal magnified risks in ways comparable to the more speculative tools of forecasting used to  assess the multiple water stresses that shape the environmental pressures on population in different areas of the world.

The following sequence of global projections of aridity are often rooted in the possibility–or near-eventuality–of rising temperature worldwide, and the pressures that these stand to place on water usage. The projection of what these water stressors will be seem to synthesize the data of rainwater levels, water tables, and ocean levels to depict the collective constraints facing agricultural communities across the world–and raising questions of what effect they might have–that will no doubt endanger rising political instability and economic hardships world-wide, in ways difficult to conceive.  The problems that underpin the mapping of the local are repeated, if with magnified risks, when trying to synthesize the data of rainwater levels, water tables, and ocean levels as a collective set of water stresses that are facing agricultural communities across the world. If California’s conditions seem due to low snowfall and few winter rains, held off the shore due to a high pressure ridge of air that seem related to the dramatic cooling of Antarctica, projections of aridity are often rooted in the possibility–or near-eventuality–of rising temperature worldwide.

The remarkably and relatively suddenly increased stresses on water-supplies world-wide are now better mapped as futures–which they indeed offer, by the World Resources Institute, a sort of barometer on the shifting dynamics of water availability in the world.  In the below charging of water stressors prospectively through 2025, based on the prospect of a world warmer by three degrees centigrade, we are pointed to the particular hot-spots in the globe.  These include the central US, which extend in arcs of desiccation poses particularly pernicious threats through much of Anatolia, Central (equatorial) Africa, and South Asia.  Specific water stressors that are projected in the map are due to the combined pressures of growing use of a limited supply of waters that higher temperatures will bring; the global map of the impact of rising temperatures poses particular problems for populations in India and China, two centers of pronounced population growth where markets where food distribution will clearly feel stresses in increasingly pronounced ways.

Crop Yield with Climate Change World Map

The pronounced pressures on fertility rates are expected to stay strong in Asia, as well as the United States, according to the below bar graph, developed by the World Resources Institute.

Fertility Rates Mapped

The areas in which the World Resources Institute predicts the most negative effects on crop production reflects the relative impact of water stresses due to projected climate change alone–revealing a far more broad impact throughout South America, northern Africa, Arabia, and Pakistan, as well as much of Australia.  (Similarly, a certain pronounced growth occurs across much of Canada–aside from Ontario–Scandinavia, and Russia, and parts of Asia, but one hardly considers these as large producers in a world that has warmed by some three degrees centigrade.)  But the highly inefficient nature of water-use–both in response to population growth and to a lack of re-use or recycling of water as a commodity and in agriculture–creates a unique heat-map, for the World Resource Institute, that will be bound to increase water stressors where much of the most highly populated and driest areas intersect.

 Water Stress Map

The rise of the temperatures is prospective, but also difficult to map in its full consequences for how it threatens the experience of the lived–or inhabited–world to the degree that it surely does.  (Indeed, how the habitable world–the ancient notion of a habitable “ecumene,” to rehabilitate the classical concept of the inhabited world and its climactic bounds by torrid zones–would change seems a scenario more clearly imagined by screenwriters of the Twilight Zone or of science fiction novels than cartographers or data visualizations.)  If we focus on the band of the hardest-hit regions alone, one can start to appreciate the magnitude of the change of restricted access to water and its restricted availability in centers of population:  the map suggests not only a decline by half of crop yields around equatorial regions, but stressors on local economies and rural areas. It staggers the mind to imagine the resulting limitations on world agriculture in this prospective map, which offers something of an admonitory function for future food and agricultural policy, and indeed international relations:

Band of hardest Hit

The shifting pressures on resources that we have too long taken for granted is sharply starting to grow.  The stressors on water will direct attention to the importance of new patterns and habits of land use, and of the potential usability or reconversion of dry lands, to compensate for these declines.  Indeed, the mapping of available water provides a crucial constraint on understanding of the inhabited–and inhabitable–world, or how we might be able to understand its habitability, bringing the resources that we have for visualizing data in ways that we might bring to bear on the world in which we want to live, or how we can best describe and envision the effects of drought as an actor in the world. Such huge qualitative shifts are difficult to capture when reduced to variations that are charted in a simple heat-map.

In a way, the constraint of water was more clearly and palpably envisioned within the earliest maps of California from the middle of seventeenth century than it is in our vision of a land that is always green, and nourished by mountain waters all along its Pacific rim.  Indeed, this image of an imagined green island of California, surrounded by waters and beside a green mainland nourished by rivers and lakes, seems extremely powerful as a mental image of the region that is increasingly remote as the water resources of the region begin to evaporate.

California Island


Filed under agriculture in america, aquifers, Climate Change, drought, mapping climate change