Starkest report on climate change and ‘unequivocal’ human involvement

‘It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.’ – Excerpts from the recently released ‘Climate change 2021: The physical science basis’ report by Intergovernmental Panel on Climate Change (IPCC)

This around 3000-page Report on climate change by United Nations’ IPCC – the sixth in its history of publication, and based on extensive work of around a decade – is the most elaborate study of scientific literature on climate change, with around fourteen thousand research articles reviewed that were accepted for publication up till end-January 2021. In addition, the Report, which was worked upon by hundreds of leading scientists from around the world, is not just a scientific endeavour; but it holds authentication by reportedly every government of the world; where the governments could suggest, but such recommendations were only admissible for inclusion in the Report after approval by the scientists involved. An August 9 Financial Times (FT) editorial ‘Time is running short to avert “hell on earth”’ pointed out in this regard: ‘A landmark assessment of climate change, released on Monday as a consensus statement by 234 international scientists, makes clear that the world faces a frightening future even if the global economy is decarbonised rapidly. Failure to cut greenhouse gas emissions deeply would lead within a few decades to what a leading climatologist called “hell on earth”.’

The Report points out the damage already done by climate change, especially during the last four decades. According to the Report, ‘Each of the last four decades has been successively warmer than any decade that preceded it since 1850. Global surface temperature in the first two decades of the 21st century (2001-2020) was 0.99°C higher than 1850-1900. Global surface temperature was 1.09 °C higher in 2011– 2020 than 1850–1900, with larger increases over land (1.59°C) than over the ocean (0.88°C). …The likely range of total human-caused global surface temperature increase from 1850–1900 to 2010–2019 is 0.8°C to 1.3°C, with a best estimate of 1.07°C. … Globally averaged precipitation over land has likely increased since 1950, with a faster rate of increase since the 1980s… Human influence is very likely the main driver of the global retreat of glaciers since the 1990s and the decrease in Arctic sea ice area between 1979–1988 and 2010–2019... Global mean sea level increased by 0.20m between 1901 and 2018. The average rate of sea level rise was 1.3mm… between 1901 and 1971, increasing to 1.9mm… between 1971 and 2006, and further increasing to 3.7mm… between 2006 and 2018’.

The Report makes it clear that climate change is happening in every corner of the world, and ‘unequivocally’ caused by humans, and time for bold action is overdue. In this regard, a recent Guardian article ‘Climate crisis “unequivocally” caused by human activities, says IPCC report’ by Damian Carrington pointed out that ‘“It is unequivocal.” Those stark three words are the first in the Intergovernmental Panel on Climate Change’s new report. The climate crisis is unequivocally caused by human activities and is unequivocally affecting every corner of the planet’s land, air and sea already. …Some heating is already inevitable. We will definitely hit 1.5C in the next two decades, whatever happens to emissions, the IPCC finds. The only good news is that keeping to that 1.5C is not yet impossible. …Even cutting emissions, but more slowly, leads to 2C and significantly more suffering for all life on Earth. If emissions do not fall in the next couple of decades, then 3C of heating looks likely – a catastrophe. And if they don’t fall at all, the report says, then we are on track for 4C to 5C, which is apocalypse territory.’

At the same time, the Report also provides five scenarios in which climate change could play out depending on the nature and extent of response in terms of remedial measures; some of which the Report points out in its last section. Damian Carrington in the same article pointed out in this regard that ‘The final section of the IPCC report addresses how future climate change can be limited. It finds that 2,400 billion tonnes of CO2 have been emitted by humanity since 1850, and that we can only leak another 400bn tonnes to have a 66% chance of keeping to 1.5C. In other words, we have blown 86% of our carbon budget already, though the report says the science is clear that if emissions are slashed then temperatures will stop rising in a decade or two and the increases in deadly extreme events will be strongly limited.’ Environment editor of the Guardian, Damian Carrington, recently indicated in a podcast titled ‘Scientists issue a climate code red’ that subsequent editions of this Report will contribute concrete guidance on possible actionable steps, and pointed out in this regard: ‘This new IPCC report is about the physical science of climate change, but it’s only one part of three, the second part will deal with how we can reduce emissions, and third part will deal with how we can, if we can, adapt to the changes, and they are coming out in the next year’.

Moreover, with regard to the five scenarios it builds, it is dependent on the extent of greenhouse gas (GHG) emissions, and its impact in terms of global warming, and curtailing it to desired and committed targets during the Paris Climate deal in 2015 of 2C, and preferably more appropriate level of 1.5C. In this regard, the Report points out: ‘Global warming of 1.5°C relative to 1850-1900 would be exceeded during the 21st century under the intermediate, high and very high scenarios considered in this report. Under the five illustrative scenarios, in the near term (2021-2040), the 1.5°C global warming level is very likely to be exceeded under the very high GHG emissions scenario, likely to be exceeded under the intermediate and high GHG emissions scenarios, more likely than not to be exceeded under the low GHG emissions scenario and more likely than not to be reached under the very low GHG emissions scenario. Furthermore, for the very low GHG emissions scenario, it is more likely than not that global surface temperature would decline back to below 1.5°C toward the end of the 21st century, with a temporary overshoot of no more than 0.1°C above 1.5°C global warming.’

Hence, individual governments need to decide, and fast, and come up with far more concrete and ambitious actions to cut down on fossil fuel reliance, and greenhouse gas emissions. That leaves the upcoming COP26 meetings in Glasgow the most important milestones for the fight against climate change. The same FT editorial pointed out in this regard: ‘The report should fortify the resolve of global leaders to agree on a far-reaching route toward net zero emissions at November’s COP26 summit in Glasgow.’

Already, a weak policy action is showing the impact of climate change across the globe, whereby even during the time of delay of COP26 from last year, climate change is making painful headlines in terms of its consequences as pointed out in a recently published Economist article ‘Where is climate change being felt most acutely?’ According to it, ‘Climate catastrophes have come thick and fast in recent months. In June an unprecedented heatwave blasted the Pacific northwest, creating the conditions for devastating wildfires. In July extreme floods in central China killed more than 30 people. In August deadly fires have been blazing across Turkey and Greece. … Many parts of the world have also experienced much more heavy precipitation (particularly in central and eastern North America and most of Europe and Asia, as well as southern Africa); more droughts have been observed elsewhere.’

Reducing reliance on fossil fuels is indeed very important to fight climate change, and there is not much space in terms of its future usage, as pointed out in a recent Economist article: ‘The budget associated with a 50:50 chance of staying below 1.5ºC allows just 500bn more tonnes of carbon dioxide to be emitted. That is about 15 years of industrial emissions at current rates (emissions from deforestation make things worse). For that to be all that is ever emitted would require the whole world, not just developed countries, to be at net-zero before 2050.’

(The writer holds a PhD in Economics from the University of Barcelona; he previously worked at the International Monetary Fund)

He tweets@omerjaved7

Copyright Business Recorder, 2021