Climate Exchange

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ransport

and

nfrastructure

Service benefits

During the construction of the Qinghai-Tibet railway

various permafrost-protective measures have been taken

to increase the stability of frozen road bases, accord-

ing to climate models and statistical projection results

and in reference to the experience and lessons of other

countries in the high latitudes. In operation, based on the

relevant climate information, the Qinghai-Tibet Railway

Corporation prepares flood-prevention resources in flood-

prone regions, with timely management of freezing or

melting events in winter. These measures guarantee the

safe running of trains, and play important roles in disaster

prevention and mitigation.

The Three Gorges project

The Three Gorges project spans the Yangtze River by the

town of Sandouping, which is located in Xiling Gorge,

Yichang, Hubei Province. The drainage area controlled

by the Three Gorges project is about one million square

km. Its total reservoir capacity is 39.3 billion cubic metres,

which can reduce the peak flow by around 27,000-33,000

cubic metres per second when handled properly. In order

to ensure its safe operation, local climate monitoring,

assessment and projection services are needed.

Local climate monitoring

TheNational Climate Center (NCC), ChinaMeteorological

Administration (CMA) have initiated special climate

observations in the Three Gorges area since 1996. This

has been fully formed as a climate monitoring net between

easily affected by engineering processes and climate change, and this

can produce thaw settlement. In addition, mountain torrents and debris

flow in summer, snow storms and ice cover in spring and winter, low

temperature, frost and sand storms all have adverse impacts on normal

railway transport.

Intensive climate monitoring

The linear structure of the railway means that a natural disaster

affecting part of the line will affect its overall operations. In order to

provide better climate services for the Qinghai-Tibet railway, on the

basis of the full application of existing meteorological data, 2009 saw

the addition of 21 new observation stations to monitor precipitation

and air temperature along the Xining-Golmud line and 16 obser-

vation stations to monitor the ground temperature for permafrost

between Golmud and Lhasa.

The permafrost environment along the Qinghai-Tibet railway is

extremely sensitive to climate change. In order to provide climate infor-

mation regarding the impacts of long-term climate change (30-50 years

in the future), future climate change on the Qinghai-Tibet plateau and

along the Qinghai-Tibet railway was projected using results from global

and regional climate models. Related climate change information was

also issued, including the annual mean temperature, the highest and

lowest temperature, and the highest summer temperature as well as the

lowest winter temperature over the Qinghai-Tibet plateau and along the

Qinghai-Tibet railway.

Landslides, debris flow and other events resulting from intensive

or continuous rainfall along the Qinghai-Tibet railway during flood

seasons (June-September) may cause transport failure. In response

to this, a tailored rainfall forecast is conducted along the railway.

Special forecast information on important weather processes is issued

one or two days in advance if moderate or above-normal rain occurs

during the flooding season. In response to the frost heave phenom-

enon happening along the north section of the Xining-Golmud line

around Qinghai Lake in winter (late November to January of the

following year), soil freezing and melting indexes were developed

with the use of observational permafrost data around the Qinghai

Lake to monitor and assess permafrost change. Monitoring informa-

tion on changes in permafrost depth is also issued. Relevant climate

information and products are issued by national and provincial

special websites, light-emitting diode electronic displays, mobile

short messages, special information reports and so on.

The

Annual Report on Climate Monitoring of

the Three Gorges Reservoir Area

Source: CMA

Image: Qinghai Meteorological Bureau

The Qinghai-Tibet railway crosses the permafrost area