Temperature increases: Negative impacts

Changes in monsoon, insufficient water supply for crops, extreme weather incidents, spread of pests and crop diseases, shifting of climatic zones are some of the impacts evident in the agriculture sector of Nepal

Regardless of insignificant greenhouse gas emission (0.025%) Nepal is vulnerable which is practically felt in context of the increased temperature especially in the Terai belt, erratic rainfall pattern, outburst of different diseases and pest, floods, etc.

Since climate threats are measured by scientists in terms of global average warming above pre-industrial levels, with 2 degrees Celsius warming stakeholders agreed to limit climate change, in terms of warming limits “well below 2C” or holding warming to 1.5C.

In spite of these efforts our planet faced the sixth successive warming year in 2016. Nepal has a mountainous and challenging topography and socio-economic conditions. Climate is influenced by the Himalayan mountain range and the South Asian monsoon.

In the country’s Himalaya, a total estimated ice reserve between 1977 and 2010 has decreased by 29 percent (129 cubic kilometer). The number of glacier lakes has increased by 11 percent and glaciers recede on an average by 38 square kilometers per year.

Increased temperature is facilitating these visible evidences causing the white glossy mountains to turn rocky and barren. The country has suffered from increased frequency of extreme weather events such as landslides, floods and droughts resulting in loss of human lives as well as high social and economic costs.

Agriculture is the major part of the country’s economy and employs approximately more than 65% of its total population and contributes to one-third of the GDP. Annual precipitation reduction is projected to be at the range of 10 to 20 percent across the country which will have a direct negative impact on agriculture production since the country’s agriculture depends upon rainwater.

Changes in monsoon, insufficient water supply for crops, extreme weather incidents, spread of pests and crop diseases, shifting of climatic zones are some of the impacts evident in the agriculture sector of Nepal. Nowadays, apples do not grow in the area where it used to grow 20 years ago.

Lower Tanahu district is unable to provide suitable chilling requirement for citrus. Due to shifting zones a significant reduction in alpine and cryospheric ecosystems may result. However, expansion in the tropical zones is seen covering most of the middle mountains and inner valleys of the region. It causes extinction of several species and landraces of crop and livestock.

Mosquito, ticks and mites have been increasing and have access even up to the high mountains. Diseases like rust and blight have shown their impact in the high hills too. It is found that an increase in temperature by 20 C would decrease meat and milk quality of ruminants and hatchability of poultry.

Increased temperature leads to increased evaporation resulting in wilt in tropical areas.

However, there are some benefits too; tropical crops like cucumber, chilli, tomato and others could be grown in the mid and high hills. Increased temperatures have shortened the grain filling duration, i.e. reduced maturity days that lead to cultivation of more crops in the same piece of land.

Similarly, desertification and forest fire are evident in tropical areas. Health problems such as dizziness, headache and fainting have increased. Rise in body temperature, drying of skin and unconsciousness are other symptoms.

Infants and elderly people are more vulnerable to illness and cannot withstand hot temperature and poor air quality.

A research carried out on possibilities of re-surviving of spring water in Kavre district by ICIMOD and NWCF revealed that the spring water resources have dried up in the hills due to extreme drought, erratic rainfall and increased temperature leading to hardships of the rural hill people for drinking water.

Besides, the country is hit by the unpredictable floods, uneven rainfall, frost, snow which directly affect agriculture production since it is basically rain-fed.

According to the UN World Meteorological Organization, the current global temperature is 1.2 degrees Celsius above the pre-industrial levels. It seems that global temperature has been rising abruptly, affecting the natural ecosystem.

It becomes urgently necessary for all the responsible citizens of every country to reduce the impact of global warming for the welfare of mother earth. Even though the effects cannot be avoided completely, efforts should be made to reduce its impact to a certain extent.

Nepal can reduce the impact of global warming by practicing the adaptation techniques like carbon sequestration by planting trees, adopting conservation tillage practices, mulching and protected cultivation practices, introduction and use of heat and pest tolerant varieties, preservation of genetic material to prevent the extinction of biodiversity, reducing green house gas emission, use of renewable source of energy (like solar), reducing carbon footprint.

Similarly, mitigating practices like conversion of C3 plant to C4 plant, reducing methane production by ruminants through improved ration feeding and genetic control, search alternative option for non renewable energy, tax for each unit carbon emission and others can be practiced.

Hence the increasing temperature above 1.5C is a serious issue for the countries like Nepal in terms of vulnerability.

Kalauni is Member of Vice President Communication Board at International Association of Students in Agriculture and Related Sciences (IAAS)