This dataset provides the final report from the Adaptation and Response in Drylands (ARID) scoping study. ARID is one of the two scoping studies funded by NASA in 2023 to identify the scientific questions and develop the initial study design and implementation concept for a new NASA Terrestrial Ecology field campaign. This report emphasizes a prioritized research agenda and an initial implementation plan, focusing on the western U.S. to deepen our understanding of national dryland processes and resources. ARID is also leveraging an extensive network of international sites and collaborators in Africa, Australia, Mexico, and South America. This global approach facilitates the evaluation, monitoring, and forecasting of drylands worldwide, ensuring a coordinated effort to address and inform solutions for the challenges facing these critical ecosystems. ARID will use cutting-edge approaches to address four Science Themes: 1) Climate Variability and Drought, 2) Ecosystem Structure, Function, and Biodiversity, 3) Carbon Cycle Interannual Variability and Long-Term Trends, and 4) Social-Ecological Systems. The scoping study performed extensive outreach, conducting over 160 meetings and events with hundreds of scientists and decision-makers across six continents, which translated to the ARID science plan being co-created with a wide range of contributors and perspectives, including remote sensing, modeling, and dryland scientists; Tribal Nations; and a range of U.S. federal entities. This report outlines a targeted plan to deploy field and NASA airborne instruments to vastly augment data derived from satellite observations that, when joined, will substantially advance quantification of drylands' large and changing role in the U.S. and in the Earth system.

This dataset provides the final report from the PAN tropical investigation of bioGeochemistry and Ecological Adaptation (PANGEA) scoping study. PANGEA is one of the two scoping studies funded by NASA in 2023 to identify the scientific questions and develop the initial study design and implementation concept for a new NASA Terrestrial Ecology field campaign. This report provides 1) the scientific rationale; 2) an initial study design concept; 3) a presentation of science questions, goals, and objectives; 4) the rationale in terms of state-of-the-art, relevance, and expected advances; 5) implementation concepts; and 6) other information to enable NASA to fully evaluate the project. This report outlines the PANGEA concept, including the PANGEA science themes, science questions, the scientific and technical advancement arising from PANGEA, the critical role of NASA remote sensing, PANGEA's research strategy and study design, PANGEA's capacity-building and training priorities, community engagement strategy, ability to enable Earth Action, and technical and logistical feasibility. The PANGEA concept reflects the voices of many and was developed in collaboration with over 800 individuals representing over 300 organizations from 42 countries across five continents. This report is provided in five languages including English, Spanish, French, Portuguese, and Indonesian.

This dataset contains global dryland literature abstracts from over the last 75 years (8218 articles) to identify areas in arid ecology that are well studied and topics that are emerging.

Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in distribution and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtropical drylands is well constrained, whereas soil moisture and ecological droughts, which drive vegetation productivity and composition, remain poorly understood in temperate drylands. Here we show that, over the 21st century, temperate drylands may contract by a third, primarily converting to subtropical drylands, and that deep soil layers will be increasingly dry during the growing season. These changes imply major shifts in vegetation and ecosystem service delivery. Our results illustrate the importance of appropriate drought measures and, as the first global study to focus on temperate drylands, highlight a distinct fate for these highly-populated areas. The data are outputs from the SOILWAT ecohydrological model, which was applied in a grid over 6 temperate drylands across the globe (South America, Southern Africa, Eastern Asia, Western and Central Asia, Western Mediterranean basin, and North America. Simulations were conducted for two time periods: 1980-2010 and 2069-2099.

This data set contains three ASCII files (.txt format). Two files contain above- and below-ground biomass and productivity data for a desert grassland in the Jornada Experimental Range, New Mexico, one file for an ungrazed treatment and the other for a light to moderately grazed treatment. The study site (32.60 N, -106.85 W, Elevation 1,350 m) is located in the Basin and Range geomorphic province at the northernmost extent of the Chihuahuan Desert, near the city of Las Cruces, New Mexico, about 60-km northwest of El Paso, Texas. The third file contains climate data for the period 1954-1992 obtained from a weather station located near the study site (32.62 N, -106.73 W, Elevation 1,300 m).Dynamics of above-and below-ground plant biomass were monitored at roughly 2-week intervals during the growing season from 1970 to 1972. Data on above-ground live biomass, recent and old dead matter, and root-crown biomass are available for one to two replications of grazed and "ungrazed" (relatively undisturbed) treatments. Total below-ground biomass was also sampled. Data were collected as part of a coordinated study over 1-3 years at ten grassland sites of the central and western United States, under the US GrasslandBiome Project of the International Biological Program (IBP).Annual above-ground net primary production (ANPP) was estimated, conservatively, by summing peak biomass of individual species, and annual below-ground net primary production (BNPP) estimated as the sum of positive increments in total root biomass.

These data represent simulated soil temperature and moisture conditions for current climate, and for future climate represented by all available climate models at two time periods during the 21st century. These data were used to: 1) quantify the direction and magnitude of expected changes in several measures of soil temperature and soil moisture, including the key variables used to distinguish the regimes used in the R and R categories; 2) assess how these changes will impact the geographic distribution of soil temperature and moisture regimes; and 3) explore the implications for using R and R categories for estimating future ecosystem resilience and resistance.

Notice to Data Users: The documentation for this data set was provided solely by the Principal Investigator(s) and was not further developed, thoroughly reviewed, or edited by NSIDC. Thus, support for this data set may be limited. This data set consists of Vegetation Water Content (VWC) data for two Soil Moisture Experiment 2004 (SMEX04) regional study areas: Arizona, USA and Sonora, Mexico. VWC was derived from the Normalized Difference Infrared Index (NDII) which was obtained from Landsat 5 Thematic Mapper (TM) imagery.

This data set was developed to describe the state of the global land cover in terms of 15 major vegetation types, plus water, before alteration by humans. It forms a complement to the historical croplands data set developed by Ramankutty and Foley (1999). By overlaying the two, one can determine the extent to which natural vegetation has been cleared for cultivation. This data set can be used directly within spatially-explicit climate and biogeochemical models. There are four total files in this data set. Two files contain the land cover types representing potential natural vegetation before human alteration, and two other files contain those points in the original data set submitted by the Principal Investigator that have been modified in order to match the land/water mask of the ISLSCP Initiative II.The geographic distribution of contemporary land cover types can be derived from remotely-sensed data. However, humans now dominate much of the world and there is little evidence of the pre-human-settlement natural vegetation or Potential Natural Vegetation (PNV). PNV, as defined here, does not necessarily represent the world's natural pre-human-disturbance vegetation. Rather, our definition of PNV represents the world's vegetation cover that would most likely exist now in equilibrium with present-day climate and natural disturbance, in the absence of human activities.