Fig. 2: Temporal variations in snow, river discharge, and drought intensity in the Colorado River Basin.
From: Multidecadal drought impacts on the Lower Colorado Basin with implications for future management
a Snow water equivalent variability in the recent 10-year period (2015–2024) (Supplementary Table 4), b naturalized discharge at Lees Ferry on the Colorado River between the UCRB and LCRB (Supplementary Table 6), and c, d GRACE Total Water Storage Anomaly (TWSA) in the UCRB and LCRB (Supplementary Table 7) and US Drought Monitor intensity (Supplementary Table 8). Linear trends in TWSA are shown by the dashed red line with trend values of −0.51 km3/yr in the UCRB and −2.0 km3/yr in the LCRB (Supplementary Table 10b). There is substantial interannual variability with TWS in the UCRB remaining fairly stable through 2011, declining sharply to 2013 during intense drought, and then stable and rising in 2019 followed by a rapid decline in 2019–2022 with a return to pre-2021 levels in 2023–2024. (D0, abnormally dry; D1, moderate drought; D2, severe drought; D3, extreme drought, D4, exceptional drought).
