Journal articles: 'North American Southwest'

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Villarreal, Aimee. "Sanctuaryscapes in the North American Southwest." Radical History Review 2019, no. 135 (October 1, 2019): 43–70. http://dx.doi.org/10.1215/01636545-7607821.

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AbstractThis article reclaims the historicity and sanctity of sanctuary as a dynamic cultural and spiritual practice and Indigenous survival strategy cultivated in regions of refuge and rebellion in the Americas. Tracing heterogeneous configurations of sanctuary in the North American Southwest during the Spanish colonial period, it compares the institution of church asylum with cross-tribal Indigenous sanctuary place-making and traditions of radical hospitality. As Indigenous people became refugees in their own homeland they capitalized on their knowledge of the landscape and banded with other persecuted and displaced peoples in “sanctuaryscapes,” vast autonomous regions and insurgent urban centers where new pan-Indigenous solidarities and identities emerged. Locating sanctuary practices within specific regional cartographies and social relations substantiates diverse autochthonous traditions of sanctuary that dramatically reorient and revitalize the origin stories that animate and also validate contemporary sanctuary movements and practices.

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Bayman, James M. "Craft economies in the north American Southwest." Journal of Archaeological Research 7, no. 3 (September 1999): 249–99. http://dx.doi.org/10.1007/bf02446113.

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Hu, Qi, and Song Feng. "Variation of the North American Summer Monsoon Regimes and the Atlantic Multidecadal Oscillation." Journal of Climate 21, no. 11 (June 1, 2008): 2371–83. http://dx.doi.org/10.1175/2007jcli2005.1.

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Abstract The North American summer monsoon holds the key to understanding warm season rainfall variations in the region from northern Mexico to the Southwest and the central United States. Studies of the monsoon have pictured mosaic submonsoonal regions and different processes influencing monsoon variations. Among the influencing processes is the “land memory,” showing primarily the influence of the antecedent winter season precipitation (snow) anomalies in the Northwest on summer rainfall anomalies in the Southwest. More intriguingly, the land memory has been found to vary at the multidecadal time scale. This memory change may actually reflect multidecadal variations of the atmospheric circulation in the North American monsoon region. This notion is examined in this study by first establishing the North American monsoon regimes from relationships of summer rainfall variations in central and western North America, and then quantifying their variations at the multidecadal scale in the twentieth century. Results of these analyses show two monsoon regimes: one featured with consistent variations in summer rainfall in west Mexico and the Southwest and an opposite variation pattern in the central United States, and the other with consistent rainfall variations in west Mexico and the central United States but different from the variations in the southwest United States. These regimes have alternated at multidecadal scales in the twentieth century. This alternation of the regimes is found to be in phase with the North Atlantic Multidecadal Oscillation (AMO). In warm and cold phases of the AMO, distinctive circulation anomalies are found in central and western North America, where lower than average pressure prevailed in the warm phase and the opposite anomaly in the cold phase. Associated wind anomalies configured different patterns for moisture transport and may have contributed to the development and variation of the monsoon regimes. These results indicate that investigations of the effects of AMO and its interaction with the North Pacific circulations could lead to a better understanding of the North American monsoon variations.

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PADGET, MARTIN. "The American Southwest Audrey Goodman, Translating Southwestern Landscapes: The Making of an Anglo Literary Region (Tucson: University of Arizona Press, 2002, $40.00). Pp. 250. ISBN 0 1865 2187 5. Molly H. Mullin, Culture in the Marketplace: Gender, Art, and Value in the Amerian Southwest (Durham: Duke University Press, 2001, $64.95 cloth, $19.95 paper). Pp. 248. ISBN 0 822 32610 8, 0 8223 2168 3. Curtis M. Hinsley and David R. Wilcox, The Lost Itinerary of Frank Hamilton Cushing (Tucson: University of Arizona Press, 2002, $50.00). Pp. 450. ISBN 0 8165 2269 3. Hal K. Rothman (ed.), The Culture of Tourism, the Tourism of Culture: Selling the Past to the Present in the American Southwest (Albuquerque: University of New Mexico Press, 2003, $34.95). Pp. 250. ISBN 0 826 32928 4." Journal of American Studies 40, no. 2 (July 27, 2006): 391–97. http://dx.doi.org/10.1017/s0021875806001435.

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Scholars have been debating what constitutes “the Southwest” for decades. Thirty years ago, geographer D. W. Meinig began his landmark study Southwest: Three Peoples in Geographical Change, 1600–1970 by stating: “The Southwest is a distinct place to the American mind but a somewhat blurred place on American maps.” For Meinig, the crucial determining factor in constituting the geographical parameters of his own study was the coincidence of Native American and Mexican American settlement patterns in Arizona, New Mexico and around El Paso, Texas. The watersheds of the Gila River in Arizona and the Rio Grande in New Mexico provide the focus of his study of the historical interaction of Indians, Mexican Americans and Anglos through the successive periods of Spanish colonialism, Mexican independence and American rule. The historical geographer Richard Francaviglia has challenged the relatively narrow focus of Meinig's study by calling for a more expansive consideration of the Greater Southwest, which, in addition to the core of Arizona and New Mexico, also includes parts of Colorado, Utah, Texas and the northern states of Mexico. He rationalizes, “The southwestern quadrant of North America is, above all, characterized by phenomenal physical and cultural diversity that regionalization tends to abstract or simplify. The more one tries to reduce this complexity, the smaller the Southwest becomes on one's mental map.”2

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Coats, Sloan, Jason E. Smerdon, Benjamin I. Cook, and Richard Seager. "Are Simulated Megadroughts in the North American Southwest Forced?*." Journal of Climate 28, no. 1 (December 31, 2014): 124–42. http://dx.doi.org/10.1175/jcli-d-14-00071.1.

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Abstract Multidecadal drought periods in the North American Southwest (25°–42.5°N, 125°–105°W), so-called megadroughts, are a prominent feature of the paleoclimate record over the last millennium (LM). Six forced transient simulations of the LM along with corresponding historical (1850–2005) and 500-yr preindustrial control runs from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are analyzed to determine if atmosphere–ocean general circulation models (AOGCMs) are able to simulate droughts that are similar in persistence and severity to the megadroughts in the proxy-derived North American Drought Atlas. Megadroughts are found in each of the AOGCM simulations of the LM, although there are intermodel differences in the number, persistence, and severity of these features. Despite these differences, a common feature of the simulated megadroughts is that they are not forced by changes in the exogenous forcing conditions. Furthermore, only the Community Climate System Model (CCSM), version 4, simulation contains megadroughts that are consistently forced by cooler conditions in the tropical Pacific Ocean. These La Niña–like mean states are not accompanied by changes to the interannual variability of the El Niño–Southern Oscillation system and result from internal multidecadal variability of the tropical Pacific mean state, of which the CCSM has the largest magnitude of the analyzed simulations. Critically, the CCSM is also found to have a realistic teleconnection between the tropical Pacific and North America that is stationary on multidecadal time scales. Generally, models with some combination of a realistic and stationary teleconnection and large multidecadal variability in the tropical Pacific are found to have the highest incidence of megadroughts driven by the tropical Pacific boundary conditions.

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Schwerin, Karl H., William C. Sturtevant, and Alfonso Ortiz. "Handbook of North American Indians. Vol. 10: Southwest." Hispanic American Historical Review 65, no. 3 (August 1985): 603. http://dx.doi.org/10.2307/2514875.

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Minnis, Paul E., Michael E. Whalen, Jane H. Kelley, and Joe D. Stewart. "Prehistoric Macaw Breeding in the North American Southwest." American Antiquity 58, no. 2 (April 1993): 270–76. http://dx.doi.org/10.2307/281969.

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The scarlet macaw (Ara macao) was an important prehistoric trade item in northern Mexico and southwestern United States. Paquimé (or Casas Grandes) in northwestern Chihuahua has been assumed to have dominated or even monopolized the macaw trade. This conclusion is a result of the fact that Paquimé is the only site with evidence of substantial macaw-breeding facilities. Two recent archaeological projects in Chihuahua indicate that macaw production was not limited to Casas Grandes. Furthermore, the political relations of production for these ritually and economically important birds differed depending on whether or not the producers were part of the complex polity centered at Casas Grandes.

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Kohler, Timothy A., and Lynne Sebastian. "Population Aggregation in the Prehistoric North American Southwest." American Antiquity 61, no. 3 (July 1996): 597–602. http://dx.doi.org/10.2307/281844.

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We attempt to clarify the role of demographic factors (size, density, history, and trajectory) in aggregation in the ancestral Puebloan Southwest, which we found obscure in Leonard and Reed (1993). In addition, we question one of the case studies from Chaco Canyon that they used to support their model, and we suggest that data from the Mesa Verde region between A.D. 700 and 1300 argue against the generality of their explanation for aggregation.

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Schwerin, Karl II. "Handbook of North American Indians. Vol. 10: Southwest." Hispanic American Historical Review 65, no. 3 (August 1, 1985): 603–6. http://dx.doi.org/10.1215/00182168-65.3.603.

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Huckell, Bruce B. "The archaic prehistory of the North American Southwest." Journal of World Prehistory 10, no. 3 (September 1996): 305–73. http://dx.doi.org/10.1007/bf02286419.

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Lewandowska, Magdalena. "Athapaskan migration to the North American Sout." Contributions in New World Archaeology 12 (December 31, 2019): 139–64. http://dx.doi.org/10.33547/cnwa.12.05.

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The arrival of the ancestors of the Apaches and Navajo to the North American Southwest, the so-called Apachean migra-tion is one of the most widely discussed issues in American archeology. Since the 19th century, after connections were disco-vered between the Athabaskan language family, potential routes and directions of migration between the Arctic and Subarctic region (inhabited by the Northern Athabaskans) and the Southwest (inhabited by the Southern Athabaskans) began to be con-sidered. During the 1930s, the Edward Sapir’s linguistic research made it possible to determine that the migration flowed from north to south, but this conclusion merely sowed the seed of research on Apachean migration, which has since blossomed with archaeological discoveries from the last 20 or 30 years. Today, we are able to pinpoint what prompted the Athabaskans’ journey; we also know of cultures such as Promontory (around the Great Salt Lake) or Dismal River (Great Plains), which we associate with the presence of the Apachean people on both sides of the Rocky Mountains. Still, many questions remain unanswered, and previous hypotheses are being verified in the light of new discoveries. No less interesting proved the results of research into some auxiliary sciences of archeology: genetics and linguistics, and the analysis of historical sources and oral tradition.The following article aims to introduce the reader to the most important and recent discoveries related to the issue of Apachean migration, and present hypotheses that have recently emerged in the scientific community, both in the context of the migration route itself and arrival in the Southwest, as well as the dates associated with them.

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Robinson, Erick, R. Kyle Bocinsky, Darcy Bird, Jacob Freeman, and Robert L. Kelly. "Dendrochronological dates confirm a Late Prehistoric population decline in the American Southwest derived from radiocarbon dates." Philosophical Transactions of the Royal Society B: Biological Sciences 376, no. 1816 (November 30, 2020): 20190718. http://dx.doi.org/10.1098/rstb.2019.0718.

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The northern American Southwest provides one of the most well-documented cases of human population growth and decline in the world. The geographic extent of this decline in North America is unknown owing to the lack of high-resolution palaeodemographic data from regions across and beyond the greater Southwest, where archaeological radiocarbon data are often the only available proxy for investigating these palaeodemographic processes. Radiocarbon time series across and beyond the greater Southwest suggest widespread population collapses from AD 1300 to 1600. However, radiocarbon data have potential biases caused by variable radiocarbon sample preservation, sample collection and the nonlinearity of the radiocarbon calibration curve. In order to be confident in the wider trends seen in radiocarbon time series across and beyond the greater Southwest, here we focus on regions that have multiple palaeodemographic proxies and compare those proxies to radiocarbon time series. We develop a new method for time series analysis and comparison between dendrochronological data and radiocarbon data. Results confirm a multiple proxy decline in human populations across the Upland US Southwest, Central Mesa Verde and Northern Rio Grande from AD 1300 to 1600. These results lend confidence to single proxy radiocarbon-based reconstructions of palaeodemography outside the Southwest that suggest post-AD 1300 population declines in many parts of North America. This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’.

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Crown, Patricia L., Jiyan Gu, W. Jeffrey Hurst, Timothy J. Ward, Ardith D. Bravenec, Syed Ali, Laura Kebert, et al. "Ritual drinks in the pre-Hispanic US Southwest and Mexican Northwest." Proceedings of the National Academy of Sciences 112, no. 37 (September 8, 2015): 11436–42. http://dx.doi.org/10.1073/pnas.1511799112.

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Chemical analyses of organic residues in fragments of pottery from 18 sites in the US Southwest and Mexican Northwest reveal combinations of methylxanthines (caffeine, theobromine, and theophylline) indicative of stimulant drinks, probably concocted using either cacao or holly leaves and twigs. The results cover a time period from around A.D. 750–1400, and a spatial distribution from southern Colorado to northern Chihuahua. As with populations located throughout much of North and South America, groups in the US Southwest and Mexican Northwest likely consumed stimulant drinks in communal, ritual gatherings. The results have implications for economic and social relations among North American populations.

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Turner II, Christy G. "Dental Transfigurement and its Potential for Explaining the Evolution of Post-Archaic Indian Culture in the American Southwest." Dental Anthropology Journal 14, no. 1 (September 4, 2018): 1–6. http://dx.doi.org/10.26575/daj.v14i1.177.

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The term "dental transfirgurement" is suggested for the non-therapeutic modification of prehistoric teeth. In North America, prehistoric dental transfigurement was a common practice only in Mesoamerica. Hence, among the few explanations possible for the rare occurrences of dental transfigurement in the prehistoric American Southwest, the msot likely one is migration, that is, the actual presence of Mesoamericans who traveled to and subsequently died in the American Southwest. One case, especially, may contribute to understanding the rapid development of the large planned prehistoric towns in and around Chaco Canyon, New Mexico. This case, the oldest example of prehistoric American Southwest dental transfigurement known so far, was part of a mass burial in one of the rooms that N. M. Judd excavated at Pueblo Bonito - a room that Judd believed had been built during the initial phase of construction of this great Chacoan town.

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Aftandilian, Dave. "What Other Americans Can and Cannot Learn from Native American Environmental Ethics." Worldviews: Global Religions, Culture, and Ecology 15, no. 3 (2011): 219–46. http://dx.doi.org/10.1163/156853511x588635.

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AbstractSince the 1960s, many have sought the solutions to North America's ecological crisis in the environmental teachings of Native American peoples. However, for the most part, Native American environmental values have not been investigated in light of the cultural contexts within which they arose. This paper draws on previously published ethnographic work among the Koyukon of interior Alaska and the Hopi of the desert Southwest to elucidate the specific environmental ethics that these two peoples have developed. Based on this contextualized evidence, augmented with teachings from the environmental ethics of other Native American peoples, I then discuss what other Americans can and cannot learn from Native American environmental ethics. Finally, I suggest alternate sources upon which non-indigenous Americans might draw to develop their own traditions of caring about and for the lands they now share with Native peoples.

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Bayman, James M., and M. Steven Shackley. "Dynamics of Hohokam obsidian circulation in the North American Southwest." Antiquity 73, no. 282 (December 1999): 836–45. http://dx.doi.org/10.1017/s0003598x00065571.

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Geochemical analyses of obsidian offer unexpected insights on the size and organization of the Hohokam regional system in the North American Southwest. Networks of obsidian circulation enlarged greatly during the Classic period as community centres with monumental architecture acquired non-local obsidian from a vast territory. This pattern confirms that prior models drastically underestimated the geographic scale of the Classic period regional system.

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Carlson, Roy L. ": Handbook of North American Indians, Volume 10: Southwest . Alfonso Ortiz." American Anthropologist 87, no. 2 (June 1985): 415–16. http://dx.doi.org/10.1525/aa.1985.87.2.02a00260.

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Rostagno, Irene. "Waldo Frank's Crusade for Latin American Literature." Americas 46, no. 1 (July 1989): 41–69. http://dx.doi.org/10.2307/1007393.

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Waldo Frank, who is now forgotten in Latin America, was once the most frequently read and admired North American author there. Though his work is largely neglected in the U.S., he was at one time the leading North American expert on Latin American writing. His name looms large in tracing the careers of Latin American writers in this country before 1940. Long before Franklin D. Roosevelt launched the Good Neighbor policy, Frank brought back to his countrymen news of Latin American culture.Frank went to South America when he was almost forty. The youthful dreams of Frank and his fellow pre-World War I writers and artists to make their country a fit place for cultural renaissance that would change society had waned with the onset of the twenties.1 But they had not completely vanished. Disgruntled by the climate of "normalcy" prevailing in America after World War I, he turned to Latin America. He started out in the Southwest. The remnants of Mexican culture he found in Arizona and New Mexico enticed him to venture further into the Hispanic world. In 1921 he traveled extensively in Spain and in 1929 spent six months exploring Latin America.

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Seager, Richard, David Neelin, Isla Simpson, Haibo Liu, Naomi Henderson, Tiffany Shaw, Yochanan Kushnir, Mingfang Ting, and Benjamin Cook. "Dynamical and Thermodynamical Causes of Large-Scale Changes in the Hydrological Cycle over North America in Response to Global Warming*." Journal of Climate 27, no. 20 (October 7, 2014): 7921–48. http://dx.doi.org/10.1175/jcli-d-14-00153.1.

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Abstract The mechanisms of model-projected atmospheric moisture budget change across North America are examined in simulations conducted with 22 models from phase 5 of the Coupled Model Intercomparison Project. Modern-day model budgets are validated against the European Centre for Medium-Range Weather Forecasts Interim Re-Analysis. In the winter half year transient eddies converge moisture across the continent while the mean flow wets the west from central California northward and dries the southwest. In the summer half year there is widespread mean flow moisture divergence across the west and convergence over the Great Plains that is offset by transient eddy divergence. In the winter half year the models project drying for the southwest and wetting to the north. Changes in the mean flow moisture convergence are largely responsible across the west but intensified transient eddy moisture convergence wets the northeast. In the summer half year widespread declines in precipitation minus evaporation (P − E) are supported by mean flow moisture divergence across the west and transient eddy divergence in the Great Plains. The changes in mean flow convergence are related to increases in specific humidity but also depend on changes in the mean flow including increased low-level divergence in the U.S. Southwest and a zonally varying wave that wets the North American west and east coasts in winter and dries the U.S. Southwest. Increased transient eddy fluxes occur even as low-level eddy activity weakens and arise from strengthened humidity gradients. A full explanation of North American hydroclimate changes will require explanation of mean and transient circulation changes and the coupling between the moisture and circulation fields.

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VanPool, Christine S. "The Shaman-Priests of the Casas Grandes Region, Chihuahua, Mexico." American Antiquity 68, no. 4 (October 2003): 696–717. http://dx.doi.org/10.2307/3557068.

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The Casas Grandes culture flourished between two well-known regions: Mesoamerica and the North American Southwest. An analysis of Medio period (A.D. 1200-1450) pottery suggests that Paquimé, the center of the Casas Grandes world, was dominated by shaman-priests. The pottery includes images that document a “classic shamanic journey” between this world and the spirit world. These images can be connected to the leaders of Paquimé and to valuable objects from West Mexico, indicating that the Casas Grandes leadership had more in common with the Mesoamerican system of shaman-leaders than with the political system of the Pueblo world of the North American Southwest.

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Styron, Richard, Julio García-Pelaez, and Marco Pagani. "CCAF-DB: the Caribbean and Central American active fault database." Natural Hazards and Earth System Sciences 20, no. 3 (March 25, 2020): 831–57. http://dx.doi.org/10.5194/nhess-20-831-2020.

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Abstract. A database of ∼250 active fault traces in the Caribbean and Central American regions has been assembled to characterize the seismic hazard and tectonics of the area, as part of the Global Earthquake Model (GEM) Foundation's Caribbean and Central American Risk Assessment (CCARA) project. The dataset is available in many vector GIS formats and contains fault trace locations as well as attributes describing fault geometry and kinematics, slip rates, data quality and uncertainty, and other metadata as available. The database is public and open source (available at: https://github.com/GEMScienceTools/central_am_carib_faults, last access: 23 March 2020), will be updated progressively as new data become available, and is open to community contribution. The active fault data show deformation in the region to be centered around the margins of the Caribbean plate. Northern Central America has sinistral and reverse faults north of the sinistral Motagua–Polochic fault zone, which accommodates sinistral Caribbean–North American relative motion. The Central Highlands in Central America extend east–west along a broad array of normal faults, bound by the Motagua–Polochic fault zone in the north and trench-parallel dextral faulting in the southwest between the Caribbean plate and the Central American forearc. Faulting in southern Central America is complicated, with trench-parallel reverse and sinistral faults. The northern Caribbean–North American plate boundary is sinistral off the shore of Central America, with transpressive stepovers through Jamaica, southern Cuba and Hispaniola. Farther east, deformation becomes more contractional closer to the Lesser Antilles subduction zone, with minor extension and sinistral shear throughout the upper plate, accommodating oblique convergence of the Caribbean and North American plates.

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Reyes, Sergio, and Daniel L. Cadet. "The Southwest Branch of the North American Monsoon during Summer 1979." Monthly Weather Review 116, no. 5 (May 1988): 1175–87. http://dx.doi.org/10.1175/1520-0493(1988)116<1175:tsbotn>2.0.co;2.

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Harrington Jr., John A., Randall S. Cerveny, and Robert C. Balling Jr. "IMPACT OF THE SOUTHERN OSCILLATION ON THE NORTH AMERICAN SOUTHWEST MONSOON." Physical Geography 13, no. 4 (October 1992): 318–30. http://dx.doi.org/10.1080/02723646.1992.10642460.

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Adler, Michael A., Todd Van Pool, and Robert D. Leonard. "Ancestral pueblo population aggregation and abandonment in the North American Southwest." Journal of World Prehistory 10, no. 3 (September 1996): 375–438. http://dx.doi.org/10.1007/bf02286420.

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Adovasio, J. M. "The Mexican Connection: Another Look at “Perishable” Relationships between Mexico and Points North." North American Archaeologist 26, no. 2 (April 2005): 209–19. http://dx.doi.org/10.2190/4b14-elv6-21c1-b8f6.

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For more than three decades, it has been clearly possible to distinguish a series of prehistoric basket making “traditions” in western North America, specifically including Mexico. While the exact nature of these traditions remains controversial, virtually no one would deny the existence of distinctive and long-lived regional perishable manufacturing trajectories with unique suites of signature artifacts and definite frontiers. Perhaps some of the most intriguing aspects of these entities are their interrelationships both in time and through time. This article reexamines the relationships between basketry production and basket making populations in Mexico, the American Southwest, and points farther afield, and concludes that certain technologies of Mexican genesis are introduced into the Southwest and elsewhere precisely at the time that a package of domesticates of Mesoamerican origin are also spreading northward. The nature of both dispersals is defined and examined and several scenarios are offered to explain these interrelated processes.

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Phillips, David A. "Adoption and Intensification of Agriculture in the North American Southwest: Notes toward a Quantitative Approach." American Antiquity 74, no. 4 (October 2009): 691–707. http://dx.doi.org/10.1017/s0002731600049015.

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Qualitative models are unable to explain the known variability in the adoption and intensification of agriculture in the prehistoric North American Southwest. Adoption of a quantitative approach (specifically, a model based on marginal costs and benefits) better accounts for that variability.

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Herweijer, Celine, Richard Seager, Edward R. Cook, and Julien Emile-Geay. "North American Droughts of the Last Millennium from a Gridded Network of Tree-Ring Data." Journal of Climate 20, no. 7 (April 1, 2007): 1353–76. http://dx.doi.org/10.1175/jcli4042.1.

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Abstract Drought is the most economically expensive recurring natural disaster to strike North America in modern times. Recently available gridded drought reconstructions have been developed for most of North America from a network of drought-sensitive tree-ring chronologies, many of which span the last 1000 yr. These reconstructions enable the authors to put the famous droughts of the instrumental record (i.e., the 1930s Dust Bowl and the 1950s Southwest droughts) into the context of 1000 yr of natural drought variability on the continent. We can now, with this remarkable new record, examine the severity, persistence, spatial signatures, and frequencies of drought variability over the past milllennium, and how these have changed with time. The gridded drought reconstructions reveal the existence of successive “megadroughts,” unprecedented in persistence (20–40 yr), yet similar in year-to-year severity and spatial distribution to the major droughts experienced in today’s North America. These megadroughts occurred during a 400-yr-long period in the early to middle second millennium a.d., with a climate varying as today’s, but around a drier mean. The implication is that the mechanism forcing persistent drought in the West and the Plains in the instrumental era is analagous to that underlying the megadroughts of the medieval period. The leading spatial mode of drought variability in the recontructions resembles the North American ENSO pattern: widespread drought across the United States, centered on the Southwest, with a hint of the opposite phase in the Pacific Northwest. Recently, climate models forced by the observed history of tropical Pacific SSTs have been able to successfully simulate all of the major North American droughts of the last 150 yr. In each case, cool “La Niña–like” conditions in the tropical Pacific are consistent with North American drought. With ENSO showing a pronounced signal in the gridded drought recontructions of the last millennium, both in terms of its link to the leading spatial mode, and the leading time scales of drought variability (revealed by multitaper spectral analysis and wavelet analysis), it is postulated that, as for the modern day, the medieval megadroughts were forced by protracted La Niña–like tropical Pacific SSTs. Further evidence for this comes from the global hydroclimatic “footprint” of the medieval era revealed by existing paleoclimatic archives from the tropical Pacific and ENSO-sensitive tropical and extratropical land regions. In general, this global pattern matches that observed for modern-day persistent North American drought, whereby a La Niña–like tropical Pacific is accompanied by hemispheric, and in the midlatitudes, zonal, symmetry of hydroclimatic anomalies.

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Adams, David K., and Enio P. Souza. "CAPE and Convective Events in the Southwest during the North American Monsoon." Monthly Weather Review 137, no. 1 (January 1, 2009): 83–98. http://dx.doi.org/10.1175/2008mwr2502.1.

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Abstract The relationship between atmospheric stability, measured as CAPE, and deep precipitating convection has been widely studied but is not definitive. In the maritime tropics, CAPE and precipitation are usually inversely correlated. In continental convection (i.e., midlatitude and tropical), no consistent relationship has been found. In this study of the semiarid Southwest, a moderate positive correlation exists, approaching 0.6. Correlations based on radiosonde data are found to be sensitive to the parcel level of origin. The strongest correlations are found by modifying the preconvective morning sounding with the maximum reported surface temperature, assuming well-mixed adiabatic layers to the level of free convection with pseudoadiabatic ascent. These results show that the upper bounds on parcel instability correlate best with precipitation. Furthermore, the CAPE–precipitation relationship is argued to depend on the convective regime being considered. The North American monsoon convective regime requires essentially only moisture advection interacting with the strong surface sensible heating over complex topography. Elimination of strong convective inhibition through intense surface sensible heating in the presence of sufficient water vapor leads to the positive CAPE–precipitation relationship on diurnal time scales. These results are discussed in light of contradictory results from other continental and maritime regions, which demonstrate negative correlations.

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Kohler, T. A., and K. M. Reese. "Long and spatially variable Neolithic Demographic Transition in the North American Southwest." Proceedings of the National Academy of Sciences 111, no. 28 (June 30, 2014): 10101–6. http://dx.doi.org/10.1073/pnas.1404367111.

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Kohler, Timothy A. "Prehistoric human impact on the environment in the upland North American Southwest." Population and Environment 13, no. 4 (June 1992): 255–68. http://dx.doi.org/10.1007/bf01271026.

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Newman, Andrew J., and Richard H. Johnson. "Dynamics of a Simulated North American Monsoon Gulf Surge Event." Monthly Weather Review 141, no. 9 (August 28, 2013): 3238–53. http://dx.doi.org/10.1175/mwr-d-12-00294.1.

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Abstract Gulf surges are transient disturbances that propagate along the Gulf of California (GoC) from south to north, transporting cool moist air toward the deserts of northwest Mexico and the southwest United States during the North American monsoon. They have been shown to modulate precipitation and have been linked to severe weather and flooding in northern Mexico and the southwest United States. The general features and progression of surge events are well documented but their detailed dynamical evolution is still unclear. In this study, a convection-permitting simulation is performed over the core monsoon region for the 12–14 July 2004 gulf surge event and the dynamics of the simulated surge are examined. Initially, convection associated with the tropical easterly wave precursor to Tropical Cyclone Blas creates a disturbance in the southern GoC on early 12 July. This disturbance is a precursor to the gulf surge on 13 July and is a Kelvin shock (internal bore under the influence of rotation) that dissipates in the central GoC. The surge initiates from inflow from the mouth of the GoC along with convective outflow impinging on the southern GoC. Continued convective outflow along the GoC generates multiple gravity currents and internal bores while intensifying the simulated surge as it propagates up the GoC. As the core of the surge reaches the northern GoC, a Kelvin shock is again the best dynamical fit to the phenomenon. Substantial low-level cooling and moistening are associated with the modeled surge along the northern GoC as is observed.

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Leonard, Robert D., and Heidi E. Reed. "Population Aggregation in the Prehistoric American Southwest: A Selectionist Model." American Antiquity 58, no. 4 (October 1993): 648–61. http://dx.doi.org/10.2307/282200.

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The settlement practices of the prehistoric Anasazi of the North American Southwest exhibited shifts from the occupation of dispersed settlements to aggregated villages in many locales both concurrently and at different times. Explaining the nature and timing of these shifts has long been a focus of interest to researchers working in the Southwest. We present a model that outlines the relations among population growth, population dispersion and aggregation, regional abandonments, the nature of specialized systems of production, labor organization, climatic change, and the role of natural selection in producing evolutionary explanations. We offer the hypothesis that aggregation is the product of changes in the organization of corporate labor related to the stabilization of specialized strategies of resource production in response to changes in environmental conditions.

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Cook, Benjamin I., Richard Seager, and Ron L. Miller. "On the Causes and Dynamics of the Early Twentieth-Century North American Pluvial." Journal of Climate 24, no. 19 (October 2011): 5043–60. http://dx.doi.org/10.1175/2011jcli4201.1.

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The early twentieth-century North American pluvial (1905–17) was one of the most extreme wet periods of the last 500 yr and directly led to overly generous water allotments in the water-limited American west. Here, the causes and dynamics of the pluvial event are examined using a combination of observation-based datasets and general circulation model (GCM) experiments. The character of the moisture surpluses during the pluvial differed by region, alternately driven by increased precipitation (the Southwest), low evaporation from cool temperatures (the central plains), or a combination of the two (the Pacific Northwest). Cool temperature anomalies covered much of the West and persisted through most months, part of a globally extensive period of cooler land and sea surface temperatures (SST). Circulation during boreal winter favored increased moisture import and precipitation in the Southwest, while other regions and seasons were characterized by near-normal or reduced precipitation. Anomalies in the mean circulation, precipitation, and SST fields are partially consistent with the relatively weak El Niño forcing during the pluvial and, also, reflect the impacts of positive departures in the Arctic Oscillation that occurred in 10 of the 13 pluvial winters. Differences between the reanalysis dataset, an independent statistical drought model, and GCM simulations highlight some of the remaining uncertainties in understanding the full extent of SST forcing of North American hydroclimatic variability.

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Stauffer, Mel R., and Don J. Gendzwill. "Fractures in the northern plains, stream patterns, and the midcontinent stress field." Canadian Journal of Earth Sciences 24, no. 6 (June 1, 1987): 1086–97. http://dx.doi.org/10.1139/e87-106.

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Fractures in Late Cretaceous to Late Pleistocene sediments in Saskatchewan, eastern Montana, and western North Dakota form two vertical, orthogonal sets trending northeast–southwest and northwest–southeast. The pattern is consistent, regardless of rock type or age (except for concretionary sandstone). Both sets appear to be extensional in origin and are similar in character to joints in Alberta. Modem stream valleys also trend in the same two dominant directions and may be controlled by the underlying fractures.Elevation variations on the sub-Mannville (Early Cretaceous) unconformity form a rectilinear pattern also parallel to the fracture sets, suggesting that fracturing was initiated at least as early as Late Jurassic. It may have begun earlier, but there are insufficient data at present to extend the time of initiation.We interpret the fractures as the result of vertical uplift together with plate motion: the westward drift of North America. The northeast–southwest-directed maximum principal horizontal stress of the midcontinent stress field is generated by viscous drag effects between the North American plate and the mantle. Vertical uplift, erosion, or both together produce a horizontal tensile state in near-surface materials, and with the addition of a directed horizontal stress through plate motion, vertical tension cracks are generated parallel to that horizontal stress (northeast–southwest). Nearly instantaneous elastic rebound results in the production of second-order joints (northwest–southeast) perpendicular to the first. In this manner, the body of rock is being subjected with time to complex alternation of northeast–southwest and northwest–southeast horizontal stresses, resulting in the continuous and contemporaneous production of two perpendicular extensional joint sets.

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Langford, Sally, Samantha Stevenson, and David Noone. "Analysis of Low-Frequency Precipitation Variability in CMIP5 Historical Simulations for Southwestern North America." Journal of Climate 27, no. 7 (March 26, 2014): 2735–56. http://dx.doi.org/10.1175/jcli-d-13-00317.1.

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Abstract Drier future conditions are projected for the arid southwest of North America, increasing the chances of the region experiencing severe and prolonged drought. To examine the mechanisms of decadal variability, 47 global climate model historical simulations performed for phase 5 of the Coupled Model Intercomparison Project (CMIP5) were assessed. On average, the CMIP5 models have higher climatological precipitation over the past century in southwestern North America than current instrumental or reanalysis products. The timing of the winter peak in climatological precipitation over California and Nevada is accurately represented. Models with resolutions coarser than 2° show a larger spread in the location and strength of the North American monsoon ridge and subsequent summer precipitation, in comparison with the higher-resolution models. Less than 20% of decadal variability in wintertime precipitation over California is associated with North Pacific sea surface temperature anomalies, a larger proportion than is associated with the tropical forcing but not sufficient for making decadal drought predictions. North American monsoon precipitation is strongly associated with local land temperatures on interannual-to-decadal time scales attributable to evaporative cooling and radiation changes driven by varying cloud cover. Soil moisture in Texas and Oklahoma in April is shown to be positively correlated with monsoon precipitation for the following summer, indicating a potential source of nonoceanic interseasonal persistence in southwestern North American hydroclimate. To make meaningful decadal predictions in the future, it is likely that forecasting will move away from sea surface temperature–driven anomaly patterns, and focus on land surface processes, which can allow persistence of precipitation anomalies via feedbacks.

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Poore, R. Z., M. J. Pavich, and H. D. Grissino-Mayer. "Record of the North American southwest monsoon from Gulf of Mexico sediment cores." Geology 33, no. 3 (2005): 209. http://dx.doi.org/10.1130/g21040.1.

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Cordell, Linda S., Stephen R. Durand, Ronald C. Antweiler, and Howard E. Taylor. "Toward Linking Maize Chemistry to Archaeological Agricultural Sites in the North American Southwest." Journal of Archaeological Science 28, no. 5 (May 2001): 501–13. http://dx.doi.org/10.1006/jasc.2001.0598.

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38

Preucel, Robert W. "Foraging, farming and village formation in the American Southwest." Antiquity 93, no. 370 (August 2019): 1092–95. http://dx.doi.org/10.15184/aqy.2019.100.

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Over 30 years ago, Paul Minnis (1985) proposed the distinction between ‘pristine domestication’ and ‘primary crop acquisition’. The former refers to the initial domestication of wild plant resources and is characterised by only a dozen or so places in the world, most notably China, the Near East and Mesoamerica. The latter refers to the local integration of crops that were domesticated elsewhere and is the more common process. The American Southwest, here defined as the U.S. states of Nevada, Utah, Arizona and New Mexico, and the Mexican states of Sonora and Chihuahua, is a classic case of primary crop acquisition. Cultigens, first maize and then squash and beans, originally domesticated in Mesoamerica, were brought north by immigrant groups who joined with local hunter-gatherer communities. The introduction of these cultigens did not initiate major immediate changes in ecological or social relationships, instead the shift to agriculture as the central subsistence practice took millennia. Just why this is the case continues to be hotly debated. The two volumes under review offer new data and valuable syntheses relevant to scholars interested in the interrelationships between the adoption of cultigens, mixed mobility strategies, and trade and exchange relationships.

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Cook, Robert A., and Aaron R. Comstock. "Evaluating the Old Wood Problem in a Temperate Climate: A Fort Ancient Case Study." American Antiquity 79, no. 04 (October 2014): 763–75. http://dx.doi.org/10.7183/0002-7316.79.4.763763.

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Abstract Schiffer (1986) first identified the old wood problem for wood charcoal-based dates from archaeological contexts in the American Southwest. The potential for dates to be skewed toward excessively old calendar ages in this region has recently generated reticence in part of the archaeological community towards including wood charcoal dates in general. Some scholars have even begun to cleanse the radiocarbon databases of regions throughout North America, partly with this presumed limitation in mind. However, the issues that contribute to the old wood problem have not been closely examined outside the arid climate of the American Southwest, resulting in some studies excluding hundreds of radiocarbon dates. The present study fills that void by examining the radiocarbon record from four well-dated Fort Ancient sites in southwestern Ohio and southeastern Indiana. Specifically, we test whether or not there are significant differences between wood charcoal and non-wood charcoal assays. Our findings suggest that wood charcoal dates should not be excluded. We explore reasons for this difference in the Eastern Woodlands and propose an ideal dating regime.

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Smithers, Gregory D. "Putting Ethnohistory to Work: Jack Forbes and the Remaking of American Historical Consciousness." Ethnohistory 68, no. 1 (January 1, 2021): 29–51. http://dx.doi.org/10.1215/00141801-8702324.

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Abstract Jack Forbes enjoyed a prolific and influential career as an ethnohistorian and educator. His groundbreaking analysis of the Southwest borderlands and interdisciplinary studies of mixed-race histories endures, and his championing of Native-centered pedagogies is now seamlessly woven into curricula throughout North America. This article examines Forbes’s efforts to remake the American historical consciousness—what Forbes called the “conqueror consciousness”—by using ethnohistorical methodologies in his scholarship and teaching. The article outlines Forbes’s career, paying particular attention to his scholarship and curriculum reform efforts during the 1960s. Those years proved crucial in Forbes’s development as a scholar and teacher and in advancing the nascent field of ethnohistory.

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Licht, Alexis, Jay Quade, Andrew Kowler, Marie de los Santos, Adam Hudson, Andrew Schauer, Katharine Huntington, Peter Copeland, and Timothy Lawton. "Impact of the North American monsoon on isotope paleoaltimeters: Implications for the paleoaltimetry of the American southwest." American Journal of Science 317, no. 1 (January 2017): 1–33. http://dx.doi.org/10.2475/01.2017.01.

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Yáñez-Arancibia, Alejandro, and John W. Day. "Water scarcity and sustainability in the arid area of North America: Insights gained from a cross border perspective." Regions and Cohesion 7, no. 1 (March 1, 2017): 6–18. http://dx.doi.org/10.3167/reco.2017.070103.

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The arid border region that encompasses the American Southwest and the Mexican northwest is an area where the nexus of water scarcity and climate change in the face of growing human demands for water, emerging energy scarcity, and economic change comes into sharp focus.

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43

Cook, Benjamin I., Richard Seager, A. Park Williams, Michael J. Puma, Sonali McDermid, Maxwell Kelley, and Larissa Nazarenko. "Climate Change Amplification of Natural Drought Variability: The Historic Mid-Twentieth-Century North American Drought in a Warmer World." Journal of Climate 32, no. 17 (July 29, 2019): 5417–36. http://dx.doi.org/10.1175/jcli-d-18-0832.1.

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AbstractIn the mid-twentieth century (1948–57), North America experienced a severe drought forced by cold tropical Pacific sea surface temperatures (SSTs). If these SSTs recurred, it would likely cause another drought, but in a world substantially warmer than the one in which the original event took place. We use a 20-member ensemble of the GISS climate model to investigate the drought impacts of a repetition of the mid-twentieth-century SST anomalies in a significantly warmer world. Using observed SSTs and mid-twentieth-century forcings (Hist-DRGHT), the ensemble reproduces the observed precipitation deficits during the cold season (October–March) across the Southwest, southern plains, and Mexico and during the warm season (April–September) in the southern plains and the Southeast. Under analogous SST forcing and enhanced warming (Fut-DRGHT, ≈3 K above preindustrial), cold season precipitation deficits are ameliorated in the Southwest and southern plains and intensified in the Southeast, whereas during the warm season precipitation deficits are enhanced across North America. This occurs primarily from greenhouse gas–forced trends in mean precipitation, rather than changes in SST teleconnections. Cold season runoff deficits in Fut-DRGHT are significantly amplified over the Southeast, but otherwise similar to Hist-DRGHT over the Southwest and southern plains. In the warm season, however, runoff and soil moisture deficits during Fut-DRGHT are significantly amplified across the southern United States, a consequence of enhanced precipitation deficits and increased evaporative losses due to warming. Our study highlights how internal variability and greenhouse gas–forced trends in hydroclimate are likely to interact over North America, including how changes in both precipitation and evaporative demand will affect future drought.

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44

Newman, Andrew J., and Richard H. Johnson. "Simulation of a North American Monsoon Gulf Surge Event and Comparison to Observations." Monthly Weather Review 140, no. 8 (August 1, 2012): 2534–54. http://dx.doi.org/10.1175/mwr-d-11-00223.1.

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Abstract Gulf surges are transient disturbances that propagate along the Gulf of California (GoC) from south to north, transporting cool moist air toward the deserts of northwest Mexico and the southwest United States during the North American monsoon. They have been shown to modulate precipitation and have been linked to severe weather and flooding in northern Mexico and the southwest United States. The general features and progression of surge events are well studied, but their detailed evolution is still unclear. To address this, several convection-permitting simulations are performed over the core monsoon region for the 12–14 July 2004 gulf surge event. This surge event occurred during the North American Monsoon Experiment, which allows for extensive comparison to field observations. A 60-h reference simulation is able to reproduce the surge event, capturing its main characteristics: speed and direction of motion, thermodynamic changes during its passage, and strong northward moisture flux. While the timing of the simulated surge is accurate to within 1–3 h, it is weaker and shallower than observed. This deficiency is likely due to a combination of weaker convection and lack of stratiform precipitation along the western slopes of the Sierra Madre Occidental than observed, hence, weaker precipitation evaporation to aid the surge. Sensitivity simulations show that convective outflow does modulate the intensity of the simulated surge, in agreement with past studies. The removal of gap flows from the Pacific Ocean across the Baja Peninsula into the GoC shows they also impact surge intensity.

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45

Van Dyke, Ruth M. "Indigenous Archaeology in a Settler-Colonist State: A View from the North American Southwest." Norwegian Archaeological Review 53, no. 1 (January 2, 2020): 41–58. http://dx.doi.org/10.1080/00293652.2020.1778779.

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46

Nauslar, Nicholas J., Benjamin J. Hatchett, Timothy J. Brown, Michael L. Kaplan, and John F. Mejia. "Impact of the North American monsoon on wildfire activity in the southwest United States." International Journal of Climatology 39, no. 3 (November 21, 2018): 1539–54. http://dx.doi.org/10.1002/joc.5899.

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47

Kligman, Ben T., Adam D. Marsh, Hans-Dieter Sues, and Christian A. Sidor. "A new non-mammalian eucynodont from the Chinle Formation (Triassic: Norian), and implications for the early Mesozoic equatorial cynodont record." Biology Letters 16, no. 11 (November 2020): 20200631. http://dx.doi.org/10.1098/rsbl.2020.0631.

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The Upper Triassic tetrapod fossil record of North America features a pronounced discrepancy between the assemblages of present-day Virginia and North Carolina relative to those of the American Southwest. While both are typified by large-bodied archosaurian reptiles like phytosaurs and aetosaurs, the latter notably lacks substantial representation of mammal relatives, including cynodonts. Recently collected non-mammalian eucynodontian jaws from the middle Norian Blue Mesa Member of the Chinle Formation in northeastern Arizona shed light on the Triassic cynodont record from western equatorial Pangaea. Importantly, they reveal new biogeographic connections to eastern equatorial Pangaea as well as southern portions of the supercontinent. This discovery indicates that the faunal dissimilarity previously recognized between the western and eastern portions of equatorial Pangaea is overstated and possibly reflects longstanding sampling biases, rather than a true biogeographic pattern.

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48

Seager, Richard, and Martin Hoerling. "Atmosphere and Ocean Origins of North American Droughts*." Journal of Climate 27, no. 12 (June 5, 2014): 4581–606. http://dx.doi.org/10.1175/jcli-d-13-00329.1.

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Abstract The atmospheric and oceanic causes of North American droughts are examined using observations and ensemble climate simulations. The models indicate that oceanic forcing of annual mean precipitation variability accounts for up to 40% of total variance in northeastern Mexico, the southern Great Plains, and the Gulf Coast states but less than 10% in central and eastern Canada. Observations and models indicate robust tropical Pacific and tropical North Atlantic forcing of annual mean precipitation and soil moisture with the most heavily influenced areas being in southwestern North America and the southern Great Plains. In these regions, individual wet and dry years, droughts, and decadal variations are well reproduced in atmosphere models forced by observed SSTs. Oceanic forcing was important in causing multiyear droughts in the 1950s and at the turn of the twenty-first century, although a similar ocean configuration in the 1970s was not associated with drought owing to an overwhelming influence of internal atmospheric variability. Up to half of the soil moisture deficits during severe droughts in the southeast United States in 2000, Texas in 2011, and the central Great Plains in 2012 were related to SST forcing, although SST forcing was an insignificant factor for northern Great Plains drought in 1988. During the early twenty-first century, natural decadal swings in tropical Pacific and North Atlantic SSTs have contributed to a dry regime for the United States. Long-term changes caused by increasing trace gas concentrations are now contributing to a modest signal of soil moisture depletion, mainly over the U.S. Southwest, thereby prolonging the duration and severity of naturally occurring droughts.

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Grantz, Katrina, Balaji Rajagopalan, Martyn Clark, and Edith Zagona. "Seasonal Shifts in the North American Monsoon." Journal of Climate 20, no. 9 (May 1, 2007): 1923–35. http://dx.doi.org/10.1175/jcli4091.1.

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Abstract Analysis is performed on the spatiotemporal attributes of North American monsoon system (NAMS) rainfall in the southwestern United States. Trends in the timing and amount of monsoon rainfall for the period 1948–2004 are examined. The timing of the monsoon cycle is tracked by identifying the Julian day when the 10th, 25th, 50th, 75th, and 90th percentiles of the seasonal rainfall total have accumulated. Trends are assessed using the robust Spearman rank correlation analysis and the Kendall–Theil slope estimator. Principal component analysis is used to extract the dominant spatial patterns and these are correlated with antecedent land–ocean–atmosphere variables. Results show a significant delay in the beginning, peak, and closing stages of the monsoon in recent decades. The results also show a decrease in rainfall during July and a corresponding increase in rainfall during August and September. Relating these attributes of the summer rainfall to antecedent winter–spring land and ocean conditions leads to the proposal of the following hypothesis: warmer tropical Pacific sea surface temperatures (SSTs) and cooler northern Pacific SSTs in the antecedent winter–spring leads to wetter than normal conditions over the desert Southwest (and drier than normal conditions over the Pacific Northwest). This enhanced antecedent wetness delays the seasonal heating of the North American continent that is necessary to establish the monsoonal land–ocean temperature gradient. The delay in seasonal warming in turn delays the monsoon initiation, thus reducing rainfall during the typical early monsoon period (July) and increasing rainfall during the later months of the monsoon season (August and September). While the rainfall during the early monsoon appears to be most modulated by antecedent winter–spring Pacific SST patterns, the rainfall in the later part of the monsoon seems to be driven largely by the near-term SST conditions surrounding the monsoon region along the coast of California and the Gulf of California. The role of antecedent land and ocean conditions in modulating the following summer monsoon appears to be quite significant. This enhances the prospects for long-lead forecasts of monsoon rainfall over the southwestern United States, which could have significant implications for water resources planning and management in this water-scarce region.

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Weiss, Jeremy L., Christopher L. Castro, and Jonathan T. Overpeck. "Distinguishing Pronounced Droughts in the Southwestern United States: Seasonality and Effects of Warmer Temperatures." Journal of Climate 22, no. 22 (November 15, 2009): 5918–32. http://dx.doi.org/10.1175/2009jcli2905.1.

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Abstract Higher temperatures increase the moisture-holding capacity of the atmosphere and can lead to greater atmospheric demand for evapotranspiration, especially during warmer seasons of the year. Increases in precipitation or atmospheric humidity ameliorate this enhanced demand, whereas decreases exacerbate it. In the southwestern United States (Southwest), this means the greatest changes in evapotranspirational demand resulting from higher temperatures could occur during the hot–dry foresummer and hot–wet monsoon. Here seasonal differences in surface climate observations are examined to determine how temperature and moisture conditions affected evapotranspirational demand during the pronounced Southwest droughts of the 1950s and 2000s, the latter likely influenced by warmer temperatures now attributed mostly to the buildup of greenhouse gases. In the hot–dry foresummer during the 2000s drought, much of the Southwest experienced significantly warmer temperatures that largely drove greater evapotranspirational demand. Lower atmospheric humidity at this time of year over parts of the region also allowed evapotranspirational demand to increase. Significantly warmer temperatures in the hot–wet monsoon during the more recent drought also primarily drove greater evapotranspirational demand, but only for parts of the region outside of the core North American monsoon area. Had atmospheric humidity during the more recent drought been as low as during the 1950s drought in the core North American monsoon area at this time of year, greater evapotranspirational demand during the 2000s drought could have been more spatially extensive. With projections of future climate indicating continued warming in the region, evapotranspirational demand during the hot–dry and hot–wet seasons possibly will be more severe in future droughts and result in more extreme conditions in the Southwest, a disproportionate amount negatively impacting society.

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Journal articles on the topic 'North American Southwest'

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