Trend analysis of hydro-climatic parameters in Sonbeel: evaluating Asia’s second largest seasonal wetland

Abstract

Wetlands are vital aquatic ecosystems that provide unique benefits to humans but are significantly impacted by climate change. Variations in temperature and rainfall can alter their health and functionality. This study focuses on Sonbeel, Asia’s second-largest seasonal wetland, to assess the trends in five hydro-climatic parameters: maximum and minimum temperatures, potential evapotranspiration (PET), rainfall, and groundwater level (GWL). The analysis employs Sen’s slope estimator and multiple trend detection methods to evaluate the temporal variability and magnitude of these trends. Among the different trend detection methods, the Innovative Trend Analysis method proves effective in identifying long-term non-monotonic trends by distinguishing between low, medium, and high value trends objectively. The study reveals a notable increase in both PET and temperatures over the study period. Conversely, trends for rainfall and GWL are declining seasonally. Specifically, temperature and PET trends are rising, while GWL is decreasing. Rainfall trends also show a decrease, which aligns with the GWL trends. To investigate the potential seasonal relationships between meteorological parameters and GWL, the study compares the trend statistics of these variables. Overall, Sonbeel’s rising temperatures and shifting rainfall patterns highlight the significant impact of climate change on this wetland. These findings underscore the importance of monitoring hydro-climatic factors to understand and address the effects of climate change on wetland ecosystems.