Hu, Z-Z., S. Yang, and R. Wu, 2003:
Long-term climate variations in China and global warming signals
COLA Technical Report No. 141, Center for Ocean-Atmosphere-Land Studies, Calverton, Maryland, USA, 36 pp.


In this work, the authors firstly analyze the observed long-term variations of seasonal
climate in China, and then investigate the possible influence of the increase in greenhouse
gas concentrations on these variations by comparing the observations with the simulations
of the second phase of the Coupled Model Intercomparison Project (CMIP2).
The long-term variations of precipitation and temperature in China are highly seasonally
dependent. The main characteristic of summer precipitation in China is a drying trend in
the north and a wetting trend in the central part. The precipitation in winter shows an
increasing trend in South and eastern-central China. Interesting features have also been
found in the transitional seasons. In spring, precipitation variations are almost opposite to
those in summer. In autumn, the precipitation decreases in almost the whole country, except
for the middle and lower reaches of the Yangtze River Valley. In addition, the seasonality of
precipitation becomes slightly weaker in recent decades in southern and eastern China.
Pronounced warming is observed in the entire country in winter, spring, and autumn,
particularly in the northern part of China. In summer, a cooling trend in central China
is particularly interesting. The variations of seasonal-mean temperature are strong coupled
with those of precipitation. Cooling (warming) trends generally coexist with wetting (drying)
trends. The coupling becomes weaker in the other seasons. It has also found that the long-
term climate variations in China may be connected to the warming trend in the Indian
A comparison between the observed seasonal climate variations and the CMIP2 simula-
tions of 16 models indicates that the observed long-term variations of winter temperature
in China are associated with the increase in greenhouse gas concentrations. However, such
a connection has not been found for the summer temperature. The tremendous uncertain-
ties among the models in precipitation simulations make it difficult to link the precipitation
variations to the global warming.
Full Text (in PDF format)