Research highlights:
A team of researchers led by Ke Zhang, Yang Hong, and Jonathan Gourley recently discovered that Global Vegetation Greening, combined with Climate Change, Promote Multi-decadal Rises of Global Land Evapotranspiration, accelerating global water cycles and potential regional drought risks. The findings were published on Nature Publishing Group Scientific Report magazine’s website (http://www.nature.com/articles/srep15956/).

The research team first generated a long-term global satellite record of land evapotranspiration using remote sensing satellite data since 1982. They investigated multi-decadal changes looking at trends between 1982 and 2013. In addition to global evapotranspiration trends, they examined vegetation greenness and general climate data including temperature, precipitation and cloudiness. Collectively, results show that during the past 32 years general increasing trends in both plant growth and evaporation with recent climate change mainly driven by vegetation greening and rising atmosphere moisture deficits. The study predicts that a continuation of these trends will likely exacerbate regional drought-induced disturbances, especially during regional dry climate phases associated with strong El Nino events.

Figure: (a) Annual anomalies of global land ET, global land air temperature and vegetation index NDVI from 1982 to 2013. A multivariate ENSO index, MEI, is shown with vertical color shading intensity. (b) Multi-decade spatial pattern of global land ET trends from 1982 to 2013.