CLIMATE CHANGE is a phenomenon that has swirled across the globe and almost whole world acknowledges it. Climate Change is commonly defined as variations in climatic pattern either on large or small scale. These variations have change the life behavior of living organisms including human, domestic animals, crops and wildlife. Around the entire globe, temperature is fluctuating, sea levels are rising and seasons are also shifting. Heat-trapping gases releasing from automobiles, power plants, deforestation and other sources are warming up. Throughout the 20th century, mean temperature of earth rose one degree Fahrenheit and scientists project if the heat trapping carbon emissions arent reduced, average earth temperature could increase by 3 to 10 degree Fahrenheit by the end of century.
Everyday solar radiations enter into earths biosphere. These radiations are reflected back and filtered by aerosols, dust particles, clouds and other atmospheric gases. But gases like CO2 are main source of adsorbing harmful radiations from sun and trapping in earths atmosphere, as a result increase the mean temperature that leads towards an adverse green house effect. The rising levels of GHGs emissions are changing the climate flaring other challenges like water security, food security, biodiversity depletion etc. during 20th century global mean sea level has risen by 10-20cm and volume of glaciers is also decreasing. In last three decades, arctic ice thickness has decreased by 40%. The migration pattern of birds, fishes and other species also make the change of habitat due to climate change that subsequently effects on animals at top of food chain.
There are a lot of incidents and devastations caused by change in climatic conditions, these changes have left avowed enigma for scientists and researchers to find out strategies to cope with these challenges. It is believed that more than 90% of natural disasters in recent years have been triggered by climate change. This situation is scarily dismal and requires immediate actions to cope with. Climate change cause hurricanes, storms and tropical storms to become more powerful. As temperature rise, there are threats of heat-related illness and even death for the furthermost vulnerable human populations. Like in 2003, extreme heat waves causes 20,000 deaths in Europe and even in Pakistan more than two thousand people died in Karachi this year. Scientists have linked the deadly heat waves to climate change and warn of more to come.
Pakistan is included in list of top ten countries which are most vulnerable to climate change. Pakistan is among three most affected countries since 2010 according to Global Climate Risk Index. Our country experiences unpredictable rainfall, variation in seasons and increased temperatures. According to global climate risk index, Pakistan in 2012 was third most affected country due to climate change. Our country is extremely vulnerable in climate change perspective and implications are already evident in form of unexpected rains, floods, water scarcity, drought etc. glaciers are the most delicate precursors of climate change. The global retreat of glaciers is certainly conspicuous. Increase in summer rains brings soil erosion, more land degradation and floods.
Pakistn is facing floods continuously for last few years. These increasingly severe floods occurred due to unpredictability of monsoon rains. Due to these monsoon rains and floods rural infrastructures, transport network, communication system and agricultural economy are suffering a lot, it is estimated that around 9 billion dollars losses incurred only. Pakistan is a disaster prone country and is frequently exposed to natural hazards like floods, drought and cyclones. With these monsoon rains and floods the rise in temperature is also predicted in Pakistan.
During last decades Pakistan economy has been facing serious problems due to heavy and repeated flooding. Two back to back floods have experienced in 2014 and 2015. These floods caused in malnutrition and hunger that resulted in overall poverty. These climatic variations have adverse effects on our agriculture. Losses during 2010 includes crop losses like sugarcane, cotton, rice, wheat, livestock loss and it also effect GDP about 3 percent. The productivity of these crops is seriously affected. In 2008-09 there were drought conditions as rainfall was less than optimum level. It is likely that there would be increase in growing degree days up to 8% in 2020 with rainfall decrease by 6% and net irrigation requirements could increase by 20%. In 2010 and 2013, rainfall more than optimum level had cause flood in different parts of Punjab.
In coming 50 years, global agriculture needs to produce more food than in the previous 10,000 years, with little or no increase in resources including water. By 2030, world needs to produce more than 50% food than being produced today. According to International Fertilizer Development Centre USA, by 2080 agriculture productivity will be reduced to 10 to 25 percent in developing countries. Due to climate change, growing season of wheat will be reduced that have negative effects on yield. Increase in air temperature shortens winter season and overall productivity of Rabi crop will be greatly affected.
According to estimates, there would be 1.2-2.8 ̊C rise maximum and 1.0-2.2 ̊C rise in minimum temperature during early and mid century in rice-wheat cropping system in Punjab. In such a future scenario 20-30% production of live stock will decrease, creating juncture in meat, poultry and milk productivity. Wheat, rice and maize contribute to 80% cereal production in Pakistan.
Crop productivity is affected by climatic variables in two ways direct and indirect impact. Direct impact includes plant evapotranspiration rate, soil moisture, plant intake status and indirect impact includes plants pest and disease influx processes which are triggered by increased temperature in atmosphere. Intense temperature results in increase in evaporation rate that ultimately leads to high demand of irrigation. Recurring floods in last few years are responsible for dribbling trend in Pakistans economy and agriculture. In Sindh and Balochistan, drought has reduced the reduced the river flow and resulting in drying up of irrigation canals, leading to severe scarcity of water. Seasonal monsoon is disturbed by climate that inflicts serious challenges to sustainable crop production.
To overcome the effect of climate change, there is need to take some practical measures such as developing new and innovative farm production practices, improve productivity and production management, changing in cropping patterns like sugar beet cultivation instead of sugarcane. Through the progress in breeding and genetics research, short duration varieties of wheat and other rabi crops should produced. Heat and moisture stress resistant varieties for wheat, rice, maize, cotton and sugarcane should produce. Flood irrigation should avoid and modern irrigation techniques should be adopted, such as use of drip and sprinkler irrigation system in order to overcome water scarcity and to enhance water use efficiency. Protect the fertile soil by reducing the seepage from canals and distribution network. By adopting these measures, we can reduce the adverse effects of climate change on crop productivity, ensuring food security and reducing poverty level in our country.
In crux, a holistic approach to devise climate resilient policies that account for a combination of adaptation and reduction of CO2 emissions are the answers to the conundrum related to climate change impacts and thus increasing Pakistans mettle to cope with the hovering cumbersome vulnerability. There should be awareness campaigns for public and government agencie compelling them to revise their environmental protection laws and these regulations should implemented strictly in whole country. Anyone who tried to break these rules or have a bad impact on environment by his actions should punished iron handedly; otherwise we may not give a safer habitat to our next generation.