ANALYSIS OF THE TONLE SAP FLOOD PULSE BASED ON REMOTE SENSING: HOW MUCH DOES TONLE SAP LAKE AFFECT THE MEKONG RIVER FLOOD?

An increase of 28 % in cropland expansion since 10 000 BCE has led to a 1.2 % enhancement in the global cropping potential, with varying efficiencies across regions. The continuous expansion has altered the support for population growth and has had impacts on climate and biodiversity, highlighting the effects of climate change. It also points out the limitations of previous studies.

Our work produces a long-term (1979–2020) high-resolution (1/30°, daily) precipitation dataset for the Third Pole (TP) region by merging an advanced atmospheric simulation with high-density rain gauge (more than 9000) observations. Validation shows that the produced dataset performs better than the currently widely used precipitation datasets in the TP. This dataset can be used for hydrological, meteorological and ecological studies in the TP.

Our study quantified the altitudinal precipitation gradients (PGs) over the Third Pole (TP). Most sub-basins in the TP have positive PGs, and negative PGs are found in the Himalayas, the Hengduan Mountains and the western Kunlun. PGs are positively correlated with wind speed but negatively correlated with relative humidity. In addition, PGs tend to be positive at smaller spatial scales compared to those at larger scales. The findings can assist precipitation interpolation in the data-sparse TP.

The Tibetan Plateau (TP), known as the Asian water tower, plays an important role in the regional climate system, while the land surface process is a key component through which the TP impacts the water and energy cycles. In this paper, we reviewed the progress achieved in the last decade in understanding and modeling the land surface processes on the TP. Based on this review, perspectives on the further improvement of land surface modelling on the TP are also provided.