AIR spotlight summary on “Climate Variability”.
AIR spotlight summary on “Climate Variability”.
It was said that winters begin after dasara and end after lohri, but it is no longer true. Sudden delays in rainfall and droughts, all these events are marking India’s climate these days.
Indications of Climate Variability
- Climate change takes place over centuries and decades which mean there is a permanent shift in the weather conditions that is rainfall patterns, temperature patterns, cyclones, droughts and hailstorms. What we are observing at present is climate variability. For example December was the warmest than the last 8 years, which was 25 degree centigrade which was 6 degrees above normal. The minimum temperature did not dip below 7.6 degree centigrade. This was because of the 90% deficit in the rainfall.
- The minimum temperature in January 2016 was 9.2 degree centigrade which was higher than the average temperature of 7.6 centigrade. This year December was very warm and in 2014 the summer was the warmest since 1880. It is the erratic behaviour we are witnessing at present.
Factors leading to Climate Change
- There are changes in the way we use energy, infrastructure, construction and food which have an impact on climate change.
- Climate variability is the by-product of growth. Throughout civilisation till the industrial revolution or as long as we were an agricultural society there was balance in the nature. Later while generating energy, urbanisation etc there was a cut in the link with nature. Instead of producers people became consumers. Due to urbanisation the infrastructure development, transportation contributes carbon dioxide. When people waste food, the transportation of food again generates carbon dioxide.
- Today there are no tax breaks or benefits to the builders if they go for energy efficient construction which can reduce energy consumption drastically. Air conditioning is more energy intensive than heating. We face this problem with the tropical countries than the temperate countries.
Impact of Climate Change
- Climate change cannot be reversed because when the temperature rises, the Pacific Ocean being the largest body of water in the world absorbs lot of heat. Then the ocean currents and the winds that blow over the ocean change and this change affects the global temperature, global weather including India’s monsoon patterns.
- We are experiencing this shift in the Pacific Ocean with some years with El Nino and some years with LA Nina which is not showing a consistent trend.
- Human activity is leading to increase in carbon dioxide which is creating certain chemical reactions in the atmosphere which in turn lead to increase in temperature. While the Arctic ice is melting, the Antarctic ice is expanding where we do not know why this is happening.
- The immediate impact of climate variability is on temperature. The most significant impact is on the shift in the monsoon pattern. It is the monsoon which leads to snowfall in Himalayas and two-thirds of the flow of water in Ganga is dependent on the snow melt and the monsoon. However we need not worry because western Himalayas will receive more rainfall and in the eastern Himalayas there is Brahmaputra River. According to present evidence the impact of climate variability or climate change will not affect India except with the increase in temperature.
- Increase in temperature leads to shifting zones of diseases. If temperature increases, the moisture regimes shift. We need to concentrate more on drainage patterns. The locality where chikungunya is spreading more is the area where there is drainage problem and stagnant water. Part of the drainage problem is also related to urbanisation because during construction of roads we ignored the traditional water drainage system.
Need of the Hour
- It is the urban middle class lifestyle which is causing this problem. The solution is also with the middle class if we change the way we live by using more of public transport, less wastage of food, smaller houses with energy efficiency the condition is bound to improve.
- Two-thirds of the global population is in Asia which is yet to develop. If we develop differently to the way the west developed, we will not have the similar trends in consumption patterns and the impact on the climate is likely to be less.
- We need to change the cropping practices and timing of the sowing according to the timing of the monsoon.
- We are moving towards solar energy, lesser reliance on coal, extension of metro services and there by promoting public transport etc will have a great impact on mitigating climate change. There should be a reduction in the need to travel rather than increasing the efficiency of the vehicle. Using rail travel as against road travel as railways are less pollution in terms of carbon dioxide. We should not waste food as it is bio degradable and it generates methane which leads to climate problem. Behavioural change is a very critical factor.
- While there are certain peak temperature in some months, in between lot of it is following the long term average temperatures. So it is too early to say that the things have deteriorated in a way that our agriculture, water supply etc is threatened. There is still not enough evidence on that.
- Climate variability is completely a man made pattern. It is not irreversible, it can be corrected if individuals and the government work together to reduce carbon dioxide emissions.