Agricultural food production is influenced by many policies, economic, and biophysical factors. Biophysical risks to agriculture production, or components of it, include natural resource shortages, climate change. It is found that climate change has a long-term influence on agrarian communities throughout the world. Crop yields will be impacted by climate change, posing a danger of food insecurity. A rising temperatures and altered precipitation patterns have a great influence on agricultural production. As a result of variations in rainfall trends, floods, rise in temperature, droughts, and negative impact on water and resources of land, climate change has the greatest influence on agricultural production. South Asia is the most susceptible region to climate change. Over 70% (roughly 1.1 billion people) of the population in South Asia lives in villages, where agriculture is the main activity, and out of those 1.1 billion, over 75% living in poverty. South Asia's annual mean temperature would climb by 3.3 degrees Celsius until the end of the current century, according to the (AR5 Synthesis Report: Climate Change 2014 — IPCC). Evidence shows that the agriculture industry in South Asian countries is in horrible shape due to these adverse climate events.

Pakistan is a country located in South Asia. Pakistan is one of the most climate-sensitive countries, although generating only 0.8 percent of atmospheric Greenhouse Gases (GHG). Pakistan ranks 135th in the world in terms of GHG emissions and is among the top ten nations that are at greater risks to climate change. Agriculture is a significant economic sector in Pakistan, generating 21% of GDP, employing 45 % labour, and accounting for nearly 60 % of exports. Aside from its financial value to Pakistan, climate change is posing severe difficulties to this industry, including rising temperatures, droughts, floods, and crop losses. Agriculture in Pakistan is particularly sensitive to climate change due to its geographical position with dry and semiarid climates. Pakistan is facing severe weather occurrences such as extreme temperatures, flooding, water shortages, droughts, and increasing disease and insect attacks. Pakistan has total cultivated land area is 23.4 million hectares (Mha), which is accounting for 29 percent of declared land, with irrigated areas accounting for 18.63 Mha, with Punjab accounting for 77 percent, Sindh 14 percent, Khyber Pakhtunkhwa 5 percent, and Balochistan 4 percent. The Pakistan agricultural sector is facing various climatic risks and many studies projected that the future scenario of agriculture production in Pakistan.

The temperature rise is one of the primary concerns that agriculture productivity in Pakistan will confront. A rise in temperature during the replantation phase increases the photosynthesis rates and reduces the rice crop growth phase, resulting in lower rice output.  Similarly, when temperature increases (+0.5 C–2 C), crop productivity is anticipated to fall by 8%–10% by 2040 (Asian Development Bank, 2017). Because of the rise in temperatures, climate change shortened the growing season, the best time for a crop to be grown. When average temperature increases, the length of a crop's growing season, or cycle of growth, i.e., the time from planting to maturity, shortens, forcing crops to mature faster and thereby preventing full crop production. Furthermore, rising temperatures are predicted to shorten crop lifecycles and reduce grain yields. As the mean temperature rises, extra water evaporates from the soil surface and transpires from plant leaves, resulting in "evapotranspiration losses." More evapotranspiration means the plant will need extra water to conduct its physiological activities and sustain maximum growth, resulting in increased irrigation or rain-water requirements in the future under water stress conditions. This increase in water requirement combines with increase in shortage of irrigation water availability due to decrease in river water flow will impact the agricultural production of Pakistan in Future.

Similarly, the shift and increase in rainfall patterns and increase in the occurrence of extreme events like floods will also be a threat to agricultural productivity posed by climate change in Pakistan. Changes in rainfall trends may be more important than temperature rise in terms of crop production, especially in an area where dry seasons are a limiting factor for agricultural production. The changing trend of rain from August to September, while those of winter will change toward March, will be expected in the Pakistan future scenario (Asian Development Bank report), and will harm crop production and even until the end of the current century, these shifts in rain peaks will persist. Intense rain during the active growing stage during the vegetative phase, affects the number of rice crops and the length of the rice-growing phase, resulting in lower rice yield.

Similarly, according to (Asian Development Bank, 2017), Western Himalayan glaciers are expected to decline over the next 50 years, creating an increase in Indus River flows that will result in floods. However, Floods have wreaked havoc on Pakistan's agriculture productivity in the past. The evidence showed that the floods in Punjab, Pakistan, had an impact on rice output between 2001 and 2010. According to the monthly assessment, the low production year of 2010 was caused by floods in the tillering stage. Furthermore, heavy localized monsoonal rain caused urban flooding in Islamabad and Rawalpindi in July 2001.

Pakistan possesses the world's biggest contiguous Indus Basin Irrigation System, which is reliant on rainfall, glaciers, and snowmelt. River inflows (142 MAF) in the Indus Basin Irrigation system are the principal source of water. Agriculture uses water (92%), industries use water (3%), and residential and infrastructure uses water (5%). According to the (Asia Development Bank, 2017), Western Himalayan glaciers are expected to decline over the next 50 years, creating an increase in Indus River flows at first, until the glacier reservoirs dried up, culminating in a 30 percent to 40 percent decline inflows over the following 50 years. Therefore, it is expected that in the future, under expected temperature stress, agriculture water requirement will increase because increase of evapotranspiration losses and expected decline in river flows due to an increase in glacial melting that will reduce water crop productivity.

About the Author: Muhammad Arslan Aslam is currently doing MPhil in "Climate Change And Sustainable Development" from Asian Institute of Technology, Thailand.