Simulation of the Plausible Climate Effects of Ecological Restoration Programs in China - Land Use Impacts on Climate - page 157

Fig. 5.12 Difference between the simulated and observed annual average temperature (a, C)
and annual precipitation (b, mm) in the overgrazing areas of Northwest China in 2010
(Fig. 5.11 a). However, the temperature is obviously lower than the observed value
in both the summer and autumn, with the difference ranging from 0.5 to 2.5 C. As
shown from Fig. 5.12 a, the stimulated annual average temperature is lower than
the observed value, and the difference between them ranges from 0.2 to 1.4 C,
indicating that there is only slight difference between the stimulated and observed
annual average temperature.
The simulated precipitation in the spring and autumn of 2010 is lower than the
observed value, and the difference between them ranges from 5 to 40 mm in most
of the months except June (Fig. 5.11 b). Figure 5.12 b reveals that the annual
precipitation of 2010 in overgrazing areas of Northwest China, especially the
southeast part of Gansu Province and northwest of Shaanxi Province, is lower than
the observed value, and the difference between them generally ranges from 5 to
30 mm. Overall, the difference between the simulated and observed monthly and
annual change of precipitation is not extremely obvious. Therefore, the WRF
model can also simulate the monthly and annual change of precipitation very well.
5.3.2.3 Effects of Grassland Degradation on the Land Surface
Temperature
The impacts of grassland degradation on the temperature in overgrazing areas of
Northwest China can be analyzed through calculating the difference in the annual
average near-surface temperature (air temperatures at 2 m above the ground)