Feature Importance Evaluation and Trend Analysis of Long Time Series of Reference Evapotranspiration in California
Abstract
Evapotranspiration (ET) is a key component in the global hydrological cycle and a decisive determinant in agricultural water management. Contrary to actual ET, reference ET (ETo) is a meteorological variable that relies on only four driving factors: solar radiation, air temperature, air humidity, and wind speed. Since the relative importance of these driving factors are region and climate specific and varies daily and seasonally, a clear understanding of their dynamic interactions can assist in accurate ETo prediction. This study employs Pearson correlation, mutual information, and random forest feature importance analyses to investigate the relative importance of meteorological driving forces of ETo in California. For this task, 36 years of daily meteorological reading from 237 standardized weather stations (1,365,823 data samples) have been analyzed. Moreover, this study investigates seasonal and annual trends of ETo and its driving factors in California using the Mann-Kendall test. To explore the daily data more accurately, it has been categorized as monthly and seasonal clusters. Also, the case study is divided into homogeneous climatic zones. Our findings indicate that solar radiation is the most influential driving factor of ETo in California. However, analyzing the monthly and seasonally clustered data reveals that vapor pressure deficit is more informative during the hot seasons, while solar radiation is more important during the fall and winter. The results of the trend analysis don't suggest a monotonic trend for ETo and its driving factors in California. However, it is shown that irrigation-oriented regions like the Central Valley are getting warmer and drier, especially during the irrigation season. This can cause problems for the agriculture and water resources of California in the future.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H45D..01A