Vol.24 No.1 2010
Consultancy
Addressing Impacts of
Glacier and Permafrost
Changes on the QinghaiTibet Plateau
By ZHANG Nan (Staff Reporter)
With a unique eco-environmental system, the QinghaiTibet Plateau plays a fundamental role in safeguarding the
local socioeconomic development and has an irreplaceable
position in ensuring eco-environmental security in China
and in the whole of Asia.
Over the past 30 years, obvious climate change,
predominantly global warming, has an extremely remarkable
impact on the cryosphere of the plateau, the world’s largest
The team conducts comprehensive studies and field trips.
area of mid- and low-altitude glaciers and permafrost. What
CAS Members and other experts in various disciplines.
is the effect of these changes on the regional socioeconomic
The rapid melting of glaciers and permafrost on
development? How to deal with them? These questions
the plateau, according to the report, not only hinders
concern both government officials and scientists, and so
development on the plateau per se, but also affects, on
the CAS Academic Divisions (CASAD) began a research
a larger scale, the regional climate process, atmospheric
project in 2006.
circulation, regional water cycles and resources. Therefore,
Climate change has led to an accelerated receding
it is necessary to address these problems in a scientific and
of mountain glaciers, says the research report, which was
effective way, so as to support the development of the Tibet
released in 2009. “As a result, mountain disasters, such as
Autonomous Region, construct a national stable barrier
glacier lake outburst floods, mud-rock flows and landslides,
for the plateau’s ecosystem, and promote coordinated and
have become more frequent and serious. In addition, the water
sustainable growth between regions.
levels of lakes are rising to inundate nearby grasslands.”
To gain first-hand information of the changes to
The warming has also caused the melting of permafrost
glaciers and permafrost on the plateau, the team conducted
in various degrees, with serious impacts on major road
comprehensive studies and field trips with the support of
construction and engineering projects, and with direct or
local governments.
potential threats to local environmental and ecological systems,
The glacier group centered on the plateau constitutes
observes the research panel, which comprised more than 20
the core group of glaciers in China and High Asia. A recent
Bulletin of the Chinese Academy of Sciences
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Vol.24 No.1 2010
survey found 36,793 individual modern glaciers on the
0.02°C, the permafrost area on the plateau is projected to
plateau in Chinese territory, covering 49,873.44 square
decrease by 8.8% in 50 years, and 13.4% in 100 years. In
kilometers, accounting for 84% of the total glacier area in
the scenario of annual temperature increase by 0.052°C, the
China and 81.6% of its total ice volume. Of those, the Tibet
figure could be 13.5% in 50 years and 46% in 100 years.
Autonomous Region has the most, with 19,594 modern
At that time, permafrost would only exist on the Qiangtang
glaciers and a total area of 24, 893 square kilometers.
Plateau and extremely high mountains.
Experts classify glaciers on the plateau into three
The recession of glaciers and permafrost on the plateau
groups: maritime glaciers, which comprise 22% of the
has brought about a series of geological disasters, with
total area of China’s existing glaciers; sub-continental (or
serious impacts on local resources and the environment.
sub-polar) glaciers, which account for 46%; and extreme
The study identified six major impacts of glacier and
continental (or polar), making up 32%.
permafrost changes on the eco-environmental system, and
Because of global warming, the experts say, the retreat
recommended necessary adaptations:
of glaciers on the plateau has been accelerated in all aspects
1. The accelerated melting of alpine glaciers results
since the 1990s. Due to various increasing rates in local
in the creation of glacier terminal lakes. With the constant
temperature and glacier thawing processes, however, the
expansion of the lakes, their dames may break, leading to
shrinkage range differs in each region. Alpine glaciers in
floods and mud and rock flows, posing direct threats to
areas like the southeast of the plateau, the north slope of the
people and traffic downstream. To deal with catastrophes,
Qomolangma and the Karakoram have the largest retreat
a survey of the lakes must be urgently stepped up so as to
range while those in the hinterland areas with continental
evaluate their safety. Surveillance and management should
climate have seen the smallest. For instance, from 1987
be conducted on risky lakes. Proactive actions could include
to 2000, the glacier area in Poiqu Basin of the central
lakes drainage through engineering projects.
Himalayas decreased by 20% with an increase in the glacier
2. The more rapid retreat of glaciers could trigger a
lake area by 47% while the area of Jialong Lake to the east
new active stage of mud and rock flows and landslides,
of the Xixiabangma (or Shishapngma) increased by 104%.
causing a disaster chain. From alpine frigid zones, to river-
From 1969 to 2000, the total glacier area in Geladandong
branch valleys and to heavy populated basins, disasters
region, where the Yangtze River originates, decreased by
could escalate in scale, destructive power and range,
1.7%. The total glacier area in the Anemaqen Mountains,
with enormous losses. Studies are urgently required on
where the headstreams of the Yellow River form, decreased
the prevention and control of mud and rock flows and
by 13.8% with a reduction of ice volume by 9.8%.
landslides, giving priority to the mechanism underlying
The future thawing of glaciers on the plateau will
the impact of treating glaciers on this kind of disasters,
depend on the rate of air temperature rise, according to
and to the predictions on their movements and potential
the study. In scenarios in which the average temperature
damages. Efforts should be made to carry out a survey
increases by 0.8°C, 2.0°C and 3°C, the total glacier area
across the region to conduct monitoring and pre-warning in
would decrease by 12%, 28% and 45%, respectively.
key townships and infrastructure, to set up a platform for
The retreat range of maritime glaciers in southeast of the
information sharing, to formulate comprehensive planning
plateau would continue to be far larger than that of extreme
for disaster mitigation, and to develop technologies for
continental glaciers in the west of the plateau.
disaster mitigation for alpine cold regions.
The researchers also found out that the warming has led
3. As a result of glacier ablation, swollen alpine lakes
to the shrinking of the permafrost area in the north of the
could flood nearby grasslands in winter and spring, reducing
plateau, raising the lower elevation boundary in permafrost
the already inadequate pasture resources and impeding the
distribution. This recession is especially obvious for island-
development of local husbandry. To deal with this calamity,
shaped areas on the fringes of permafrost. From the 1960s
evaluation should be made of the potential risks of the lakes,
to the 1990s, this boundary rose by about 70 meters on
background survey should be conducted of nearby eco-
average. In the scenario of annual temperature increase by
environmental systems, and an early-warning system should
36 Bulletin of the Chinese Academy of Sciences
Vol.24 No.1 2010
Consultancy
be set up for lake disasters. At the same time, studies on a
to protect and utilize local tourism resources. Mountain
contingency plan for grassland inundation and upstream
glaciers are a rare and precious tourism resource on the
diversion engineering should be carried out. Schemes should
plateau. As an alternative resource for local tourism, it
also be drafted for the utilization of lake water resources for
would become a new growth point for local socioeconomic
mitigating the negative effects of higher river levels and for
development. The receding of glaciers would have two
benefiting local people’s production and livelihood.
major impacts on the resources. First, it would lower the
4. The glacier receding seriously affects the regional eco-
quality of the glacier resources; and second, it would lead to
environment and socioeconomic development. In the short
disasters, damaging tourism facilities and threaten the safety
term, it tends to increase water volume of rivers, unbalancing
of tourists. Great attention should be paid to the changes of
those rivers that depend on glaciers. In addition, the ablation
the Rongbuk Glacier, with active prevarication measures
of glaciers mostly takes place in the peiord of heavy
for the possible disasters caused by constant ablation. A
precipitation, significantly raising the frequancey and process
tourism planning should be prepared in a scientific way, with
of floods. In the long run, with the constant retreat of glaciers,
a comprehensive evaluation of the possible impacts of the
there will be a decrease in glacier melt water, progressively
ablation on terminal moraine, climbing camps and tourism
reducing the water supply to rivers and posing the threat of
resorts. Monitoring and early warning systems for other
them drying up. To address the problem, efforts should be
glacier tourism resources should also be conducted.
made to strengthen water resource protection and gradually
6. Permafrost degradation would seriously affect the
establish an observation network for variations in glaciers,
performance of major engineering projects, especially roads
glacier runoff, river runoff, lake area and water levels, and
on the plateau. To ensure the safety of the Qinghai-Tibet
climate factors, and to establish a mechanism for network
Highway, various measures could be adopted to deal with
management and data sharing. At the same time, constant
different kinds of road section by taking into account the
vigilance should be exercised by combining remote sensing
intensification of global warming and the impacts of human
technology with field observations for the long-term and
engineering activities.
dynamic monitoring of any unexpected retreat of glaciers, and
With the objective of effectively addressing the
to set up an effective early-warning system so as to upgrade
geological hazards caused by glacier retreat and permafrost
the decision-making capacity to address problems of water
degradation and their negative impacts, the report calls on the
resources caused by melting glaciers. By gradually adopting
central government to increase support to relevant provinces
tree and grass planting and husbandry controls according
and regions (Tibet Autonomous Region in particular) in terms
to scientific planning, improvements will be made to the
of human, material and financial resources, so as to set up and
ecosystem of basins mainly dependent on glaciers for water
improve a comprehensive system for the dynamic and real-
supply, and increase water conservation capacity.
time monitoring of disasters caused by glacier lakes, mud and
5. The retreat of glaciers makes it more difficult
rock flow and permafrost degradation.
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