Observed response of tropical river streamflow to climate change -
evidence from a national database
Abstract
We analyzed streamflow records from more than 300 stations across
Thailand, a tropical country in Southeast Asia. Temporal changes in
runoff yield were assessed over the 1960-2015 period, highlighting a
prominent downward trend over the last two decades. To identify
potential drivers of these changes, gridded data products representing
precipitation, temperature, evapotranspiration, and land cover were also
assessed. We found that runoff yield is primarily driven by annual
precipitation, which has experienced an unprecedented decline since
2010. Two sub-regions with particularly robust data coverage reflected a
spatial contrast in hydrologic response: a more consistent response of
runoff yield to precipitation is observed in the sub-region
characterized by a high density of forest cover relative to the region
characterized by high cropland cover. This feature underscores the need
to take land use and irrigation practices into account when forecasting,
and determining management strategies for, tropical river streamflow in
a warming climate.