Figure 2
Precipitation trends in the EIB and 16 closed inland basins were
detected based on the GPM satellite data. Figure 3 shows the trends in
annual and monthly precipitation for each basin for 2002–2020. There
was a slightly increasing trend in annual precipitation in the EIB, with
the magnitude of 3.7 mm/10a. The decreasing trend was detected in the
BLB, CSB, IIRB, JB, QPB and TuRB; these basins are mainly distributed in
the western and northern EIB. The annual precipitation was increasing in
the remaining ten basins, in which the HRB had the largest increase of
52.3 mm/10a. The magnitude of the increase in the HRB accounted for
28.6% of the mean annual precipitation in this basin. The ratio of
increases to the mean annual precipitation was also relatively higher at
the TB (9.9%), IMPB (7.3%), and GHCB (6.9%). The magnitude of the
decrease in the IIRB also accounted for -10.8% of the mean annual
precipitation in this basin. The ratio of increases or decreases to the
mean annual precipitation was within ±5% in the remaining closed
basins. The annual precipitation trends were non-significant in the EIB
and each closed basin. The increasing trend in the HRB was the closest
to being significant (at p < 0.05). However, annual
precipitation showed significant decreasing trends in three sub-basins
(not shown), including the Issyk-Kul Lake, Southwest Caspian Sea, and
Ural River basins; the magnitudes of these decreasing trends were -86.7,
-68.8, and -57.3 mm/10a, respectively.