ICESat Derived Crustal Flexure as Caused by Expansion of an Endorheic Lake on the Tibetan Plateau

Abstract:

Lake expansion in the Tibetan Plateau (TP) has been measurable since the 1970’s, and there has been a marked increase in these expansion rates since the year 2000. From 2003 to 2009 Siling Co, an endorheic lake in the TP, has seen an areal increase from around 2000km2 to nearly 2220km2 with a lake-level increase of more than 4m. This rapid expansion corresponds to around 9Gt of added water load into the lake and onto the lithosphere. Lake expansion and volume rates in the region have been well documented using various satellite‐derived and in‐situ datasets. However, lithospheric flexure as caused by these increased crustal loads has not been studied in great detail, and ICESat data has not been exploited for this purpose until now. ICESat data was utilized to determine flexure rates along several transects adjacent to an endorheic lake (Siling Co) on the TP. The rates were calculated for each kilometer from the lake boundary and show a clear “bowl-like” trend with flexure rates decreasing as distance increases from the Siling Co lakeshore.