Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls?
Wl. Chameides et al., Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls?, P NAS US, 96(24), 1999, pp. 13626-13633
Citations number
61
Categorie Soggetti
Multidisciplinary
Journal title
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
The effect of atmospheric aerosols and regional haze from air pollution on
the yields of rice and winter wheat grown in China is assessed. The assessm
ent is based on estimates of aerosol optical depths over China, the effect
of these optical depths on the solar irradiance reaching the earth's surfac
e, and the response of rice and winter wheat grown in Nanjing to the change
in solar irradiance. Two sets of aerosol optical depths are presented: one
based on a coupled, regional climate/air quality model simulation and the
other inferred from solar radiation measurements made over a 12-year period
at meteorological stations in China. The model-estimated optical depths ar
e significantly smaller than those derived from observations, perhaps becau
se of errors in one or both sets of optical depths or because the data from
the meteorological stations has been affected by local pollution. Radiativ
e transfer calculations using the smaller, model-estimated aerosol optical
depths indicate that the so-called "direct effect" of regional haze results
in an approximate to 5-30% reduction in the solar irradiance reaching some
of China's most productive agricultural regions. Crop-response model simul
ations suggest an approximate to 1:1 relationship between a percentage incr
ease (decrease) in total surface solar irradiance and a percentage increase
(decrease) in the yields of rice and wheat. Collectively, these calculatio
ns suggest that regional haze in China is currently depressing optimal yiel
ds of approximate to 70% of the crops grown in China by at least 5-30%. Red
ucing the severity of regional haze in China through air pollution control
could potentially result in a significant increase in crop yields and help
the nation meet its growing food demands in the coming decades.