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Evaluating the response of vegetation to climate change is relevant to improving the management of both human and natural systems. Here, we quantify the response of the MODIS-based enhanced vegetation index (EVI) to temperature, precipitation, and large-scale natural variability across the South-Central U.S. for summer (JJA) from 2000 to 2013. We find statistically significant relationships between climate and EVI that vary across the region and are distinct for each land cover type: the mean coefficient of determination (R 2 ) between EVI and climate is greatest for pasture (0.61 ± 0.13) and lowest for forest (0.55 ± 0.14). Among the climate variables, three-month cumulative precipitation has the strongest influence on summer vegetation, particularly in semi-arid west Texas and eastern New Mexico. Summer monthly maximum temperature plays an important role in the eastern half of Texas and Oklahoma, moderated by the influence of both Atlantic and Pacific teleconnection indices over inter-annual time scales. Based on these relationships, we train, cross-validate, and, where statistically significant relationships exist, combine this multivariate predictive model with projected changes in teleconnection indices and statistically-downscaled temperature and precipitation from 16 CMIP5 global climate models to quantify future changes in EVI. As global mean temperature increases, projected EVI decreases, indicative of stressed and dry vegetation, particularly for grasslands as compared to other land types, and in Oklahoma and western, central and Gulf Coast Texas for mid- and end-of-century. These trends have potentially important implications for agriculture and the regional economy, as well as for ecosystems and endemic species that depend on vegetation. [ABSTRACT FROM AUTHOR]

Climate change is expected to alter the mean and variability of future spring and summer drought and wet conditions during the twenty-first century across North America, as characterized by the Standardized Precipitation Index (SPI). Based on Coupled Model Intercomparison Project phase 5 simulations, statistically significant increases are projected in mean spring SPI over the northern part of the continent, and drier conditions across the southwest. Dry conditions in summer also increase, particularly throughout the central Great Plains. By end of century, greater changes are projected under a higher radiative forcing scenario (RCP 8.5) as compared to moderate (RCP 6.0) and lower (RCP 4.5). Analysis of projected changes standardized to a range of global warming thresholds from +1 to +4 °C reveals a consistent spatial pattern of wetter conditions in the northern and drier conditions in the southwestern part of the continent in spring that intensifies under increased warming, suggesting that the magnitude of projected changes in wetness and drought may scale with global temperature. For many regions, SPI interannual variability is also projected to increase (even for regions that are projected to become drier), indicating that climate may become more extreme under greater warming, with increased frequency of both extreme dry and wet seasons. Quantifying the direction and magnitude of projected future trends from global warming is key to informing strategies to mitigate human influence on climate and help natural and managed resources adapt. [ABSTRACT FROM AUTHOR]

• Some types of weather affect Americans' belief that they have experienced global warming. • Americans associate hot, dry days and extreme drought with global warming. • People often fail to interpret extreme rainfall or flooding as due to global warming. Public perceptions of climate change in the United States are deeply rooted in cultural values and political identities. Yet, as the public experiences extreme weather and other climate change-related impacts, their perceptions of the issue may shift. Here, we explore whether, when, and where local climate trends have already influenced perceived experiences of global warming in the United States. Using a large national survey dataset (n = 13,607), we compare Americans' experiences of climate with corresponding trends in seven different high-resolution climate indicators for the period 2008 to 2015. We find that increases in hot dry day exposure significantly increases individuals' perceptions that they have personally experienced global warming. We do not find robust evidence that other precipitation and temperature anomalies have had a similar effect. We also use multilevel modeling to explore county-level patterns of perceived experiences with climate change. Whereas the individual-level analysis describes a likely causal relationship between a changing climate and individuals' perceived experience, the multilevel model depicts county-level changes in perceived experience resulting from particular climate trends. Overall, we find that exposure to hot dry days, has a modest influence on perceived experience, independent of the political and socio-demographic factors that dominate U.S. climate opinions today. [ABSTRACT FROM AUTHOR]

Historically, extreme hot, dry summers over the South‐Central (SC) United States are dominated by an isolated dome of high pressure centered over the region. Applying self‐organizing map techniques to North American Regional Reanalysis reanalysis and historical and future Coupled Model Intercomparison Project version 5 (CMIP5) simulations, we find that as the world warms, this type of high‐pressure system is likely to become stronger and more frequent—even after removing the effect of surface warming on the expansion of the lower atmosphere. These projected changes appear to be related to self‐reinforcing ocean‐atmosphere interactions in a warming world. Specifically, intensified easterly winds over the Atlantic and Gulf of Mexico drive an increase in the meridional sea surface temperature gradient due to oceanic Ekman transport, which further enhances the ridge of high pressure extending across the SC United States: a dynamical relationship that increases confidence in regional projections of summer drought risk over the SC United States. Plain Language Summary: Water is already a scarce resource in the South‐Central United States. The region's frequent droughts pit its agriculture community against the energy industry, ecosystem managers, and growing municipalities in competition for the region's increasingly over‐allocated water resources. Our study identifies the daily weather patterns associated with historical drought and examines how these are likely to change as the world gets warmer. We find that the main weather pattern associated with drought, an isolated dome of high pressure centered over the South‐Central region, is likely to become stronger and more frequent by the late 21st century under human‐induced climate change. We also find that this appears to be related to self‐reinforcing ocean‐atmosphere interactions: in other words, the warmer the world gets, the stronger this pattern becomes. This is not good news for the region, as it establishes a physical mechanism that explains why projected summer rainfall is expected to decrease, and droughts to become stronger and longer, as climate continues to change. Key Points: Extreme hot and dry summers over the South‐Central United States are historically characterized by an isolated dome of high pressure over the regionFuture projections indicate that this high‐pressure system is likely to become stronger and more frequent, as climate changesProjected changes in the high‐pressure system appear to be related to self‐reinforcing ocean‐atmosphere interactions in a warming world [ABSTRACT FROM AUTHOR]