38
an increase in precipitation and intensity. The highest percentage of soil loss occurs
in the medium and high regions of Tajikistan, Kyrgyzstan, Eastern Uzbekistan, and
East Kazakhstan. This suggests that there will be more occasions for soil losses at
medium and high altitudes than has ever been experienced in the past. Consequently,
high soil erosion may lead to high sedimentation in rivers, lakes, and reservoirs, and
these are critical for flooding and water pollution (Yang et al. 2003) (Fig. 4.12).
4.6 Rainfall Erosivity and Soil Erosion at the National Level
In the baseline period, Kyrgyzstan has an estimated average rainfall erosivity of
869.7 MJ mm ha
−1
h
−1
year
−1
. The MIROC5 and MPIESMLR scenarios (RCP 2.6
and RCP 8.5, respectively) project an increase in the mean rainfall erosivity ranging
from 27.9% to 50.1% and from 0.9% to 27%. The BCCCSM1.1 scenarios also projected a mean increase of 6.3% for all periods and a decrease (−7.8%) for
BCCCSM1.1-8.5 in the 2070s.
In Kazakhstan, we calculated the mean values of rainfall erosivity of 374.3 MJ
mm ha
−1
h
−1
year
−1
during the baseline period. From MIROC5, BCCCSM1.1, and
MPIESMLR (both scenarios), we note an increase in the mean rainfall erosivity of
5.3% to 27.3%, 11.6% to 23.2%, and 0.6% to 15.7%, respectively, in this country
with a slight increase in the northern part and a significant increase in the eastern
Fig. 4.9 Soil erosion for different scenarios for the 2030s and 2070s according to the RCP 2.6 and
RCP 8.5 scenarios driven by the BCCCSM1.1, IPSLCM5ALR, MIROC-5, and MPIESMLR GCM
models
4 Projected Rainfall Erosivity and Soil Erosion in Central Asia
an increase in precipitation and intensity. The highest percentage of soil loss occurs
in the medium and high regions of Tajikistan, Kyrgyzstan, Eastern Uzbekistan, and
East Kazakhstan. This suggests that there will be more occasions for soil losses at
medium and high altitudes than has ever been experienced in the past. Consequently,
high soil erosion may lead to high sedimentation in rivers, lakes, and reservoirs, and
these are critical for flooding and water pollution (Yang et al. 2003) (Fig. 4.12).
4.6 Rainfall Erosivity and Soil Erosion at the National Level
In the baseline period, Kyrgyzstan has an estimated average rainfall erosivity of
869.7 MJ mm ha
−1
h
−1
year
−1
. The MIROC5 and MPIESMLR scenarios (RCP 2.6
and RCP 8.5, respectively) project an increase in the mean rainfall erosivity ranging
from 27.9% to 50.1% and from 0.9% to 27%. The BCCCSM1.1 scenarios also projected a mean increase of 6.3% for all periods and a decrease (−7.8%) for
BCCCSM1.1-8.5 in the 2070s.
In Kazakhstan, we calculated the mean values of rainfall erosivity of 374.3 MJ
mm ha
−1
h
−1
year
−1
during the baseline period. From MIROC5, BCCCSM1.1, and
MPIESMLR (both scenarios), we note an increase in the mean rainfall erosivity of
5.3% to 27.3%, 11.6% to 23.2%, and 0.6% to 15.7%, respectively, in this country
with a slight increase in the northern part and a significant increase in the eastern
Fig. 4.9 Soil erosion for different scenarios for the 2030s and 2070s according to the RCP 2.6 and
RCP 8.5 scenarios driven by the BCCCSM1.1, IPSLCM5ALR, MIROC-5, and MPIESMLR GCM
models
4 Projected Rainfall Erosivity and Soil Erosion in Central Asia