Telecoupling of environmental and ecological conditions in aridlands is associated with the Land Surface Template (LST) and precipitation (PPT) patterns. Variation in telecoupling may be shaped by multiple factors, and local (< 1 km2) observations may be similar to regional (> 250 km2) patterns under some conditions and different under others. For example, extreme drought events can influence vegetation over large regions, and overwhelm the effects of many LST factors. Multi-year high PPT periods that resulted in perennial grass production on some sites have received less attention. In the Chihuahuan Desert region, individual rainfall events in the monsoon season are stochastic, suggesting that high PPT is localized and widespread positive telecoupling is improbable. Yet, multi-year high PPT periods may homogenize stochastic rainfall patterns through time and across space to overwhelm local LST conditions, and in this way promote positive telecoupling that is not possible in single years.
Results/Conclusions
Using remote sensing data from 1983-present and a suite of harmonized LST datasets, we sought to quantify telecoupling beginning locally at the Jornada LTER site in New Mexico and expanding to the Chihuahuan Desert in the US and northern Mexico. Our goal was to determine if patterns in climate are coupled to patterns in vegetation response during a wet period or if local heterogeneity in soils and land use decouple climate and vegetation response. We hypothesized that high PPT would aggregate through time to become more regionally-similar and/or more probable, and that increasing duration of a local forcing event at JRN would increase its similarity to the larger region. Our results show that telecoupling in this region is instigated by the aggregation of sustained high PPT and/or extreme high PPT events through time, but its pattern within the rainfall area is contingent on local factors. Wet periods are changing and will play an important role in shaping the future pattern and dynamics of aridlands. By identifying and quantifying patterns in telecoupling, we develop new insight on how climate and landscapes interact, and how these landscapes may respond to future climates.