April vegetation dynamics and forest-climate interactions in central appalachia

Abstract

The study of land-atmosphere (L-A) interactions is an emerging field in which the effects of the land on the atmosphere are strongly considered. Though this coupled approach is becoming more popular in atmospheric research, L-A interactions are not fully understood, especially in temperate regions. This study provides the first in-depth investigation of L-A interactions and their impacts on near-surface climate conditions in the Appalachian region of the Eastern United States. By way of statistical analysis, we explore vegetation dynamics, L-A interactions, and the consequences for near-surface climate, along with the competing effects of the albedo (energy) and moisture (evapotranspiration and soil moisture) feedback. Based on the results from linear regression, composite, and correlation analyses, we conclude that: (1) a statistically significant increasing trend in April vegetation exists from 1982 to 2015 in central Appalachia; (2) there was empirical evidence that this increasing vegetation trend was significant and altered near-surface climatic conditions, as indicated by significantly enhanced latent heat flux, 2 m-specific humidity, and soil moisture; and (3) the dominant biogeophysical process responsible for the changes in near-surface climate conditions could be the positive moisture feedback process.