ann
(Ann)
#1
inner mongolia’s extreme weather
In environmental terms, imperial pastoralism was the particular adaptation
required by grassland diversity that the dynasty had to undergo in order to
establish and maintain its regime from Manchuria to Xinjiang. Temperature
and precipitation are the most ecologically significant factors. Grasslands
cover about 70 percent of today’s IMAR, which as China’s third largest
province sprawls over 1. 18 million kilometers^2 or 12 percent of its terri-
tory. 870 , 000 km^2 of this expanse comprises between 25 percent and
33 percent of China’s grasslands. These temperate steppes, which mainly
lie across a plateau confluence of dry alpine rain shadows to the west and
wetter ocean winds to the east, are“extremely sensitive to interannual
variation in climate and land-usage change.”This position creates a marked
precipitation gradient that declines from east to west over this Mongolian
plateau itself. Overall, IMAR temperate steppe zones are generally colder
(average annual temperature− 2 to 4 C) and drier ( 250 to 400 millimeters
per year) in winter than their North American prairie equivalents.^31
These average differences, however, mask extraordinaryfigures that
render steppe winters measurably harsher than prairie winters. In modern
terms this works out tofluctuation across a range of as much as 30 Cina
single day. Qing sources affirm a continuity in these conditions, exhibiting
only a nominal difference in degree:“There is extreme cold in the early
morning and late evening, while at noon there is a sudden heat so that
there can be a difference of forty“degrees”(du) between these periods.”^32
In summer the area receives almost all its precipitation, and it is
possible for about 30 percent of the annual rainfall to hit an area during
one hour in some parts of Mongolia with commensurateflooding and
erosion. In general, wetter areas in the east taper off to drier areas in the
west. This“strong seasonal” tendency has a commensurate effect on
plant cover as well as the animal populations that subsist on it, particu-
larly in winter and spring when the food supply can drop to starvation
levels to cause mass herd mortality.^33
These conditions also contribute to extreme weather events across rela-
tively short time spans. The dynamic relations that produce these conditions
remain incompletely understood. For example, until 2009 it had been gen-
erally, and incorrectly, assumed that one of the most pastorally devastating
of these events, drought, somehow precipitates another catastrophic event,
the Mongoliandzud.Thedzudis the notorious steppe winter event pro-
duced by extreme cold temperatures that causes mass mortalities of live-
stock, mainly by impenetrably freezing out forage. The last time such a
128 Across Forest, Steppe, and Mountain
