28 Apr 1.5 Degree Celsius Survive and Thrive
My grandfather predicted that last year was hotter than all the previous years. He usually says that temperature has been increasing each year and the rainfall pattern has disturbed. He explains nowadays cropping pattern has significantly differed from his generation. Monsoon has shifted a bit later, wet times being more wetted due to over precipitation and dry periods facing a greater problem of drought. Grandfather also describes the rituals followed by Nepalese farmer like marrying frogs and worshipping God Indra, appealing for rain. As the Nepalese farmers are dependent on rainfall and weather condition, agriculture has been worst affected by global warming. Misbalanced hydrological cycle due to temperature rise has posed a threat of extreme precipitation or enhanced dry period, ultimately resulting in food insecurity. According to a recent data, the annual reduction in precipitation is estimated to be in the range of 10 to 20% across the country.
I met a kid studying in 8th standard, who was wondering about the fact, though Nepal contribute very little to Global Green House Gas Emission (only 0.025% of global emission), Nepal has to face very hazardous impact of temperature increase and had been ranked as a fourth vulnerable country to climate change in the world. In 1985, an avalanche breached the headwater of Koshi river, Dig Tsho lake and slid into the river, overtopping the dam. The event destroyed hydro-electricity projects, bridges, houses and farmland not only in Nepal but also to the Bihar State of India. In 2015, Bardiya district experienced the worst flood in six decades which submerged more than 1,000 houses in Gulariya. The Same year an avalanche on Mount Everest near Everest Base Camp killed 16 Nepali guides and the death toll from the unexpected storm in Annapurna appeared to be more than 30. Based on National Adaptation Program of Action 2010, out of 75 districts, 29 districts are highly vulnerable to natural hazards, 22 districts to drought, 12 districts to glacial lake outburst floods, and nine districts to flooding.
Increased temperature causes the white glossy mountains to turn rocky and barren. Due to ice melting level of snow-fed rivers has raised initially but it would reduce in long-term ultimately resulting in drying of the river. The incidence of flood and glacier outburst has increased in the Himalayan region. Similarly, desertification, forest fire have been evident in tropical areas. Health problems such as dizziness, headache, and fainting have been increased. The rise in body temperature, drying of skin and unconsciousness are other symptoms. Especially, infants and elderly people are more vulnerable to illness and cannot withstand hot temperature and poor air quality. Every year an average of 688 deaths occur only due to extreme heat. Central Asia is currently experiencing one of the hottest heat waves ever recorded.
Changes in monsoon, insufficient water supply for crops, extreme weather incidents, the spread of pests and crop diseases, shifting of climatic zones are some of the impacts evident in the agriculture sector of Nepal. Nowadays, the apple does not grow in the area where it used to grow 20 years ago. Lower Tanahu district is unable to provide a suitable chilling requirement for citrus. Due to shifting zones, there may occur a significant reduction in alpine and cryospheric ecosystems. However, expansion in the tropical zones is seen covering most of the middle mountains and inner valleys of the region. It causes the extinction of several species and landraces of crop and livestock. The incident of 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 high hills too. It is found that increase in temperature by 20 C would decrease the meat and milk quality of ruminants and hatchability of poultry. Also with the increase in 10 C in crops, physiological activities are enhanced by 10 times due to greater respiration. Increased temperature lead to increased evaporation resulting problem of wilt in tropical areas. However, there are some benefits too, tropical crops like cucumber, chilly, tomato and others could be grown in the mid and high hill. Increased temperature have shortened the grain filling duration i.e. reduced maturity days that leads to the cultivation of more number of the crop in the same piece of land. According to FAO, “Early decades of the twenty-first century will see a moderate warming of 1‑2
According to FAO, “Early decades of the twenty-first century will see a moderate warming of 1‑2oC, resulting in reduced crop yields in seasonally dry and tropical regions, while crop and pasture yields in temperate regions may benefit. Further warming in the second half of the century will negatively affect all regions, although agriculture in many developing countries in semi-tropical and tropical regions will bear the brunt of the effects.” According to the UN World Meteorological Organization, the current global temperature is 1.2 degrees Celsius above the preindustrial levels. It seems that global temperature has been rising abruptly, affecting the natural ecosystem. It become urgent necessary for all the responsible citizen 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 reduced its impact to certain extent. Nepal can reduce the impact of global warming by practicing the adaptation techniques like 0-increasing 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), promoting awareness campaign regarding global warming, reducing carbon footprint. Similarly, mitigating practices like conversion of C3 plant to C4 plant, reducing methane production by ruminants through genetic control, search alternative option for non renewable energy, pay tax for each unit carbon emission and others can be practiced.
Written by Arati Joshi, IAAS Nepal