Tuesday, November 29, 2016

Overview of Climate and Climate Pattern in Bhutan

Bhutan is a small landlocked country characterized by rugged terrain with elevations ranging from around 100 to more than 7000 meters above the sea level. In order to separate areas with similar sets of potentials and constraints for assessment of land suitability and potential productivity, Bhutan can be broadly categorised in to three agro-ecological zones:

1.      Sub-tropical (100-1800 masl) zone constitute the Himalayan foothills in the southern belt (LCMP, 2010). It is characterized by high humidity and heavy rainfall with temperature ranging from 150 C to 300C all year round.
2.      Warm temperate (1800-3600 masl) zone are the main central valleys characterized by cool winters and hot summers with moderate rainfall. Summer temperatures are usually from 150 C to 260 C while winter temperature ranges from -40C to 150C.
3.      Alpine (3600-7500 masl) zone is composed of snow-capped peaks and alpine meadows above with very cold winters and cool summers.

Bhutan currently has forests coverage of 70.46% (LCMP, 2010) of the land area and sequestration by forests is estimated at 6.3 million tons of carbon. Emissions in 2013 are estimated at 2.2 million tons of carbon making Bhutan a net sink for green house gases. However, Bhutan remains highly vulnerable to emerging climate change impacts due to its geographic location and dependence of country’s economy on climate-sensitive sectors such as agriculture, hydropower and forestry. Climate variability has shown considerable impact on the glaciers and snows in the Himalayan Mountains, which are the source of drinking water, irrigation of agriculture fields and generation of hydropower.

Existing information show further warming of the atmosphere in Bhutan, as is happening globally. This change is occurring against the background of high climate variability, but the signal is clear. Air temperatures are rising steadily and this warming has seen Bhutan experiencing more warm weather and extreme events such as glacier retreat posing GLOF threats, reduction in availability of agricultural water, change in phenology, loss of habitat and increased incidences of pest and diseases over the recent years. Further, number of studies revealed rapid changes in average temperatures, precipitation patterns, and increased risks of climate related hazards in the recent years.  Department of Agriculture reported that the climate-induced hazards such as excessive rains, flash floods, windstorms, hailstorm, droughts etc. have caused massive loss and damage to farming households. There is also evidence of new pests and diseases affecting crops and livestock production.