5.2. Asia
Climate change will impose significant stress on resources throughout the Asian
region. Asia has more than 60% of the world's population; natural resources
already are under stress, and the resilience of most sectors in Asia to climate
change is poor. Many countries are socioeconomically dependent on natural resources
such as water, forests, grassland and rangeland, and fisheries. The magnitude
of changes in climate variables would differ significantly across Asian subregions
and countries. The climate change sensitivity of a few vulnerable sectors in
Asia and the impacts of these limits are presented in Table
TS-6. The region's vulnerability to climate change is captured in Table
TS-7 for selected categories of regions/issues.
| Table TS-6: Sensitivity of selected Asian regions
to climate change. |
 |
| Change in Climatic Elements and Sea-Level
Rise |
Vulnerable Region
|
Primary Change
|
Impacts
|
|
Primary
|
Secondary
|
|
0.5-2°C
(10- to 45-cm sea-level rise) |
Bangladesh Sundarbans |
- Inundation of about 15% (~750 km2)
- Increase in salinity |
- Loss of plant species
- Loss of wildlife |
- Economic loss
- Exacerbated insecurity and loss of employment |
|
4°C
(+10% rainfall) |
Siberian permafrosts |
- Reduction in continuous permafrost
- Shift in southern limit of Siberian permafrost by ~100-200 km
northward |
- Change in rock strength
- Change in bearing capacity
- Change in compressibility of frozen rocks
- Thermal erosion |
- Effects on construction industries
- Effects on mining industry
- Effects on agricultural development |
|
>3°C
(>+20% rainfall) |
Water resources in Kazakhstan |
- Change in runoff |
- Increase in winter floods
- Decrease in summer flows |
- Risk to life and property
- Summer water stress |
|
~2°C
(-5 to 10% rainfall; 45-cm sea-level rise) |
Bangladesh lowlands |
- About 23-29% increase in extent of inundation |
- Change in flood depth category
- Change in monsoon rice cropping pattern |
- Risk to life and property
- Increased health problems
- Reduction in rice yield |
|
| Table TS-7: Vulnerability of key sectors to impacts
of climate change for select subregions in Asia. Key to confidence-level
rankings is provided in Section 1.4 of Technical
Summary. |
|
| Regions |
Food and Fiber |
Biodiversity |
Water Resources |
Coastal Ecosystems |
Human
Health |
Settlements |
|
| Boreal Asia
|
Slightly resilient
****
|
Highly
vulnerable
***
|
Slightly resilient
***
|
Slightly resilient
**
|
Moderately vulnerable
**
|
Slightly or not vulnerable
***
|
|
| Arid and Semi-Arid Asia |
|
|
|
|
|
|
| - Central Asia |
Highly
vulnerable
****
|
Moderately vulnerable
**
|
Highly
vulnerable
****
|
Moderately vulnerable
**
|
Moderately vulnerable
***
|
Moderately vulnerable
***
|
| - Tibetan Plateau |
Slightly or not vulnerable
**
|
Highly
vulnerable
***
|
Moderately vulnerable
**
|
Not applicable
|
No
information
|
No
information
|
|
| Temperate Asia |
Highly
vulnerable
****
|
Moderately vulnerable
***
|
Highly
vulnerable
****
|
Highly
vulnerable
****
|
Highly
vulnerable
***
|
Highly
vulnerable
****
|
|
| Tropical Asia |
|
|
|
|
|
|
| - South Asia |
Highly
vulnerable
****
|
Highly
vulnerable
***
|
Highly
vulnerable
****
|
Highly
vulnerable
****
|
Moderately vulnerable
***
|
Highly
vulnerable
***
|
| - Southeast Asia |
Highly
vulnerable
****
|
Highly
vulnerable
***
|
Highly
vulnerable
****
|
Highly
vulnerable
****
|
Moderately vulnerable
***
|
Highly
vulnerable
***
|
|
5.2.1. Agriculture and Food Security
Food insecurity appears to be the primary concern for Asia. Crop production
and aquaculture would be threatened by thermal and water stresses, sea-level
rise, increased flooding, and strong winds associated with intense tropical
cyclones (high confidence). In general, it is expected that areas in mid-
and high latitudes will experience increases in crop yield; yields in lower
latitudes generally will decrease. A longer duration of the summer season should
lead to a northward shift of the agroecosystem boundary in boreal Asia and favor
an overall increase in agriculture productivity (medium confidence). Climatic
variability and change also will affect scheduling of the cropping season, as
well as the duration of the growing period of the crop. In China, yields of
several major crops are expected to decline as a result of climate change. Acute
water shortages combined with thermal stress should adversely affect wheat and,
more severely, rice productivity in India even under the positive effects of
elevated CO2 in the future. Crop diseases such as wheat scab, rice
blast, and sheath and culm blight of rice also could become more widespread
in temperate and tropical regions of Asia if the climate becomes warmer and
wetter. Adaptation measures to reduce the negative effects of climatic variability
may include changing the cropping calendar to take advantage of the wet period
and to avoid the extreme weather events (e.g., typhoons and strong winds) during
the growing season. [11.2.2.1]
Asia dominates world aquaculture, producing 80% of all farmed fish, shrimp,
and shellfish. Many wild stocks are under stress as a result of overexploitation,
trawling on sea-bottom habitats, coastal development, and pollution from land-based
activities. Moreover, marine productivity is greatly affected by plankton
shift, such as seasonal shifting of sardine in the Sea of Japan, in response
to temperature changes induced during ENSO. Storm surges and cyclonic conditions
also routinely lash the coastline, adding sediment loads to coastal waters.
Effective conservation and sustainable management of marine and inland fisheries
are needed at the regional level so that living aquatic resources can continue
to meet regional and national nutritional needs. [11.2.4.4]
