Explained: Reading new climate report

The IPCC reports

The latest warnings have come in the second part of IPCC’s Sixth Assessment Report which talks about climate change impacts, risks and vulnerabilities, and adaptation options. The first part report was released in August last year. That one was centred around the scientific basis of climate change. The third and final part of the report, which will look into the possibilities of reducing emissions, is expected to come out in April.

The Assessment Reports, the first of which had come out in 1990, are the most comprehensive evaluations of the state of the earth’s climate. Hundreds of experts go through every available piece of relevant, published scientific information to prepare a common understanding of the changing climate. The four subsequent assessment reports, each thousands of pages long, came out in 1995, 2001, 2007 and 2015. These have formed the basis of the global response to climate change.

What is new

The Sixth Assessment Report does not say anything remarkably new. Over the years, each assessment report has built on the work of the previous ones, adding more evidence, information and data, so that most of the conclusions about climate change and its impacts have far greater clarity, certainty and wealth of new evidence now, than earlier.

But that does not mean this is only a reiteration of previous statements. Each of these reports have also progressively expanded the scope of their assessment, and introduced fresh information about different aspects of climate change.

The latest report has, 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. For example, it has said Mumbai is at high risk of sea-level rise and flooding, while Ahmedabad faces serious danger of heat-waves. Such granular information was not available in previous assessment reports. Flooding in Mumbai and heat-waves in Ahmedabad are common occurrences. What this report has done is to look at granular data affecting these events, and quantified these risks, so that there is a much clearer understanding of the threats posed to these cities.

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.

Other findings

The report has said the impacts of climate change were far greater, more frequent and vastly more disruptive than previously understood.

“Based on increased observations and a better understanding of processes, we now know that the extent and magnitude of climate change impacts on nature are greater than previously assessed. The impacts we see today are appearing much faster, they are more disruptive and more widespread than we expected 20 years ago,” it has said.

The report has said that while strong actions to reduce greenhouse gas emissions in the near term, in the next 20 years, would substantially reduce the threats, and the projected damages, they would not eliminate them all. If the temperature rise crossed the threshold of 1.5°C from pre-industrial times, then many changes could be irreversible.

The need to take adaptation measures is therefore very important, the report has stressed. It has recognised progress being made to adapt to the new situation, but pointed out that, in most places, it was nowhere close to what is required to be done. It has said the gaps in adaptation was a result of lack of funds and political commitment, and also the absence of reliable information and a sense of urgency.

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.

“Adaptation is essential to reduce harm, but if it is to be effective, it must go hand in hand with ambitious reductions in greenhouse gas emissions because with increased warming, the effectiveness of many adaptation options declines,” the report has said.

What now

IPCC reports form the scientific basis on which countries across the world build their policy responses to climate change. These reports, on their own, are not policy prescriptive: They do not tell countries or governments what to do. They are only meant to present factual situations with as much scientific evidence as is possible.

And yet, these can be of immense help in formulating the action plans to deal with climate change. The detailed nature of this latest report, with respect to regional and sectoral impacts, presents actionable intelligence, particularly for countries that lack the resources or the capacity to make their own impact assessments. The fact that these findings are the product of the combined understanding of the largest group of experts on climate science lends it a credibility greater than any individual study.

These reports also form the basis for international climate change negotiations that decide on the responses at the global level. It is these negotiations that have produced the Paris Agreement, and previously the Kyoto Protocol. The Paris Agreement, negotiated on the basis of the Fifth Assessment Report, seeks to keep the rise in global temperatures “well below” 2°C from pre-industrial times, while “pursuing efforts” to limit it to 1.5°C. The Sixth Assessment Report, however, has presented lots of evidence to suggest that pursuing a 2°C target could be disastrous, and more ambitious actions need to be taken to keep the temperature rise within 1.5°C.

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