First we try to make a difference between the key concepts of weather and the climate – some use the terms interchangeably. Weather refers to the state of the atmosphere including its temperature, wind speed, humidity, precipitation and rain or snow etc happening in a place at a specific moment in time. It is influenced by the oceans, land surfaces and ice sheets which together with the atmosphere form the “climate system.” Climate is the normal pattern of weather for a particular place over several decades. In the broadest sense, it is the statistical description of the state of the climate system. Therefore, climate change must simply be regarded as a change in global or regional climate patterns. In particular, scientists use it to describe changes in the statistical properties of the climate system that persists for several decades or longer—usually at least 30 years. These statistical properties include averages, variability and extremes. It is apparent from the mid-to-late 20th century onwards and attributed largely to the increase level of carbon dioxide produced by the use of fossil fuels.
Although it is certain that Earth has naturally warmed up and gotten colder in the past, and that climate had always changed due to natural processes such as the water and energy cycles, these changes had always been much slower and caused by phenomena such as slow shifts in the Earth’s orbit and changes in solar and volcanic activity. Whereas now, human activities within a period of just 200 years have caused sudden shifts in the climate by releasing billions of tons of carbon dioxide into the atmosphere and adding substantially to the green house effect. The major drivers of the current climate change are greenhouse gas emissions, most importantly carbon dioxide and methane, which are primarily released when fossil fuels are burnt. These have increased rapidly since the Industrial Revolution in the 1800s and reached their highest level in the decade to 2010, having even brought about extinctions of species. If continued this way, it will be the end for us.
Deforestation is another leading cause of climate change, which had badly affected the climate system. People cut down millions of trees from the forest land for residential and industrial purposes, though they are a chief source of absorbing carbon dioxide and protect the atmosphere from damage. Deforestation has a multiplier negative effect of emission of greenhouse gases resulting from an increase in livestock farming. As more and more trees are cleared off, extensive land is spared for livestock production. However, animals on the land create waste, which produces methane, a very harmful greenhouse gas – which negatively affects the environment and contributes to climate change.
Pakistan is among the top 10 countries which are vulnerable to the impact of changing weather patterns. The fact is that only 5.7% of its total land is under forest cover, whereas according to global standards it should be more than 20%. We can see that our country’s climate has become increasingly volatile over the past several decades
The surge in the use of chemicals in the domestic sphere and in agriculture in the shape of fertilisers also plays a part in climate change. The high rate of application of nitrogen-rich fertiliser has effects on the heat storage of cropland and runoff excess fertilisers create dead zones in oceans. High nitrate levels in ground water due to over fertilisation are a cause of concern for human health.
The human population is growing exponentially, which is posing severe threat to the climate system. According to The Intergovernmental Panel on Climate Change (IPCC), the leading international body for the assessment of climate change, there is a more than 95% probability that human activities over the past 50 years have warmed our planet. Climate change seems to be the mother of all the problems of the 21st century and an issue of grave concern for people’s lives and the country’s future.
Pakistan’s three major climate challenges are related to floods, drought and sea intrusion. The consequences are water and food scarcity, health issues and population displacement. Now in pre-monsoon days we have observed flooding in the northern parts of Hazara and Malakand, which had caused complete breakdown in lives of people dwelling there. Houses were badly damaged as water accumulated in houses. It turned roads into rivulets and almost all thoroughfares were inundated, making movement of vehicular traffic difficult and causing a great inconvenience to the public.
We need to take corrective measures by creating awareness among the general public and especially the youth, who can participate in the battle against climate change. The government should arrange seminars and conferences and include it in the science curriculum at school and college level, so the successive generations can be able to know about the catastrophic impact of climate change.