We used the Terrestrial Ecosystem Model (TEM, version 4.0) to estimate net primary
production (NPP) in China for contemporary climate and NPP responses to elevated CO2 and
climate changes projected by three atmospheric general circulation models (GCMs): Goddard
Institute for Space Studies (GISS), Geophysical Fluid Dynamic Laboratory (GFDL) and Oregon
State University (OSU). For contemporary climate at 312.5 ppmv CO2, TEM estimates that China
has an annual NPP of 3,653 TgC yr-1 (1012 gC yr-1). Temperate broadleaf evergreen forest is the
most productive biome and accounts for the largest portion of annual NPP in China. The spatial
pattern of NPP is closely correlated to the spatial distributions of precipitation and temperature.
Annual NPP of China is sensitive to changes in CO2 and climate. At the continental scale,
annual NPP of China increases by 6.0% (219 TgC yr-1) for elevated CO2 only (519 ppmv CO2).
For climate change with no change in CO2, the response of annual NPP ranges from a decrease of
1.5% (54.8 TgC yr-1) for the GISS climate to an increase of 8.4% (306.9 TgC yr-1) for the
GFDL-q climate. For climate change at 519 ppmv CO2, annual NPP of China increases
substantially, ranging from 18.7% (683 TgC yr-1) for the GISS climate to 23.3% (851 TgC yr-1)
for the GFDL-q climate. Spatially, the responses of annual NPP to changes in climate and CO2
vary considerably within a GCM climate. Differences among the three GCM climates used in the
study cause large differences in the geographical distribution of NPP responses to projected climate
changes. The interaction between elevated CO2 and climate change plays an important role in the
overall response of NPP to climate change at 519 ppmv CO2.