Regional and National Agroecosystem Ltar Climate Representativeness.

The Long-Term Agroecosystem Research (LTAR) network is a new way to approach the challenge of sustainable agricultural intensification at the regional and national scale. The 18 LTAR sites span the country, and although a few gaps remain, notably in California, the major agricultural regions are represented. At another level of detail, the next question to address is how well the LTAR network represents the conditions required to produce major crops, and conversely, what cropping systems does each LTAR site represent? We compared the LTAR sites with gridded climate products, notably the PRISM 800 m precipitation and temperature products, and the daily gridMET 4 km precipitation and temperature products. Both products were compared to long-term observations of the Walnut Gulch Experimental Watershed LTAR site, a 150 km² area surrounding the town of Tombstone Arizona. Production statistics for major crops are available at the county level and remote sensing products related to vegetation estimate such as Landsat, at a gross scale, production with great spatial detail, available at regional/national scale. At the national scale, climate datasets show a general warming trend across the LTAR sites with summer periods showing a warming trend with no significant change in precipitation while winter periods exhibiting an increasing trend in temperature and precipitation. Drought conditions at the site level are compared with production from major crops statistics and remote sensing proxies to identify the influence of water-limited conditions on production. This climate representativeness assessment is supported by the use of emerging tools for analysis, visualization, and data sharing technologies with the main focus of collaboration at a distance and applying reproducibility concepts in the LTAR network.