The latest second part of IPCC’s Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) has warned of multiple climate change-induced disasters in the next two decades even if strong action is taken to reduce the emissions of greenhouse gas emissions. The report talks about climate change impacts, risks and vulnerabilities, and adaptation options.

The report has said the impacts of climate change were far greater, more frequent and vastly more disruptive than previously understood. Nonetheless, the report, which for the first time focuses on solutions, and called for Climate Resilient Development that combines climate adaptations with greenhouse gas reductions.

The report has also , for the first time, made an assessment of regional and sectoral impacts of climate change. It has included risks to, and vulnerabilities of, mega-cities around the world. It has said the ability of human beings, and natural systems, to cope with the changing climate was already being tested, and further rise in global warming would make it even more difficult to adapt.

Also for the first time, the IPCC report has looked at the health impacts of climate change. It has found that climate change is increasing vector-borne and water-borne diseases such as malaria or dengue, particularly in sub-tropical regions of Asia. It has also said deaths related to circulatory, respiratory, diabetic and infectious diseases, as well as infant mortality, are likely to increase with a rise in temperature. Increasing frequency of extreme weather events like heatwaves, flooding and drought, and even air pollution was contributing to under-nutrition, allergic diseases and even mental disorders.

Noting that over 3.5 billion people, over 45% of the global population, were living in areas highly vulnerable to climate change, the report identifies India as one of the vulnerable hotspots, with several regions and important cities facing a very high risk of climate disasters such as flooding, sea-level rise and heat-waves. The report mentioned that India would face extreme climate scenarios on many fronts – from rising sea levels to groundwater scarcity, from extreme weather patterns to a decline in crop production, besides a rise in health risks. The report also projected an increase in river ‘runoff’ in the Indus, Ganga, and Brahmaputra river basins, which contribute water to the densely populated areas of south Asia, between 2050 and 2100.

For example, it has said Mumbai is at high risk of sea-level rise and flooding, while Ahmedabad faces serious danger of heat-waves.Several cities, including Chennai, Bhubaneshwar, Patna and Lucknow, are approaching dangerous levels of heat and humidity.

At present, wet-bulb temperatures in India rarely exceed 31 degrees C, with most of the country experiencing maximum wet-bulb temperatures of 25-30 degrees C, according to IPCC.

It notes that if emissions are cut, but only by the levels currently promised, many parts of northern and coastal India would reach extremely dangerous wet-bulb temperatures of over 31 degrees C towards the end of the century.

If emissions continue to rise, wet-bulb temperatures will approach or exceed the un-survivable limit of 35 degrees C over much of India, with the majority of the country reaching wet-bulb temperatures of 31 degrees C or more.

Wet-Bulb Temperatures

It is a measure that combines heat and humidity.A wet-bulb temperature of 31 degrees Celsius is extremely dangerous for humans, while a value of 35 degrees is unsurvivable for more than about six hours, even for fit and healthy adults.

The report has said if the temperature rise crossed the threshold of 1.5°C from pre-industrial times, then many changes could be irreversible.It has pointed out that there were “feasible and effective” adaptation options which could reduce the risks to people and nature. But the effectiveness of these options decreases sharply with further increases in temperature.

LEARNING FROM HOME/WITHOUT CLASSES/BASICS

CLIMATE CHANGE:  Climate change refers to any change in climate over time whether due to natural variability or as a result of human activity. The term is commonly used interchangeably with global warming and green house effects and refers to increasing concentration of greenhouse gases in the atmosphere that traps sun’s heat causes changes in weather pattern on a global scale.

              Greenhouse gases allow sunlight (shortwave radiation) to pass through the atmosphere freely, where it is then partially absorbed by the surface of the Earth. Greenhouse gases are able to trap heat (longwave radiation) in the atmosphere, keeping the Earth’s surface warmer than it would be if they were not present. These gases are the fundamental cause of the greenhouse effect. Increases in the amount of greenhouse gases in the atmosphere enhances the greenhouse effect which is creating global warming and consequently climate change.

The principal forcing greenhouse gases are:

Carbon dioxide (CO2); Methane (CH4); Nitrous oxide (N2O); Fluorinated gases

PARIS AGREEMENT

The Paris Agreement is an agreement within the United Nations Framework Convention on Climate Change (UNFCCC) dealing with greenhouse gas emissions, mitigation and adaptation. The Paris agreement was signed in 2015 by 195 countries. The Paris Agreement entered into force on 4 November 2016.  The Paris Agreement mandates all countries to take action to minimise the impact of climate change as per their voluntary commitments and individual capacity.It asks richer countries to help out poorer countries: to give them capital to invest in green technologies, but also to help them brace for a changing world.

It sets a global goal of keeping global average temperatures from rising 2°C (compared to temperatures of pre-Industrial Revolution) by the end of the century.

Adaptation

Governments agreed to strengthen societies’ ability to deal with the impacts of climate change;  provide continued and enhanced international support for adaptation to developing countries.

Loss and damage

The agreement also recognizes the importance of averting, minimizing and addressing loss and damage associated with the adverse effects of climate change.