Climate change has not stopped for the Covid-19 pandemic. With greenhouse gas concentrations in the atmosphere at record levels, emissions heading in the direction of pre-pandemic levels, and the world set to see its warmest five years on record, the threat from climate change is as grave as ever, the United in Science 2020 report says.
The projections are not in line with the targets to keep the rising global temperature well below 2 degrees Celcius or at 1.5 degrees Celcius, above pre-industrial levels.
The report, compiled by the World Meteorological Organisation (WMO) under the direction of the UN Secretary-General, highlights the increasing and irreversible impacts of climate change, which affects glaciers, oceans, nature, economies, and human living conditions.
“This has been an unprecedented year for people and the planet. The Covid-19 pandemic has disrupted lives worldwide. At the same time, the heating of our planet and climate disruption has continued apace,” UN Secretary-General António Guterres said in a foreword of the report. Key findings of the report indicate that transformational action can no longer be postponed if the Paris Agreement targets are to be met.
The projections are not in line with the targets to keep the rising global temperature well below 2 degrees Celcius or at 1.5 degrees Celcius, above pre-industrial levels. (Shutterstock)
While the carbon dioxide emission fell sharply due to Covid-19 induced lockdown globally, methane emissions from human activities have continued to increase. The current emission of CO2 and methane are not on track with respect to the Paris Agreement.
Meanwhile, the average global temperature for 2016–2020 is expected to be the warmest on record, about 1.1 degrees Celcius above 1850-1900. In the five-year period 2020–2024, the chance of at least one year exceeding 1.5 degrees Celcius above pre-industrial levels is 24 per cent, the report concluded.
Changing snow and ice dynamics
The report highlights the risk to people from flooding and other catastrophic events as changing hydrological conditions trigger changes in snow and ice dynamics. According to the report, "By 2050, the number of people at risk of floods will increase from its current level of 1.2 billion to 1.6 billion. In the early to mid-2010s, 1.9 billion people, or 27 per cent of the global population, lived in potentially severely water-scarce areas. In 2050, this number will increase to 2.7 to 3.2 billion people."
The average global temperature for 2016–2020 is expected to be the warmest on record. (Shutterstock)
Climate change is projected to increase the number of water-stressed regions and worsen water shortage situations. The annual runoff from glaciers will reach peak globally by the end of the 21st century, following which, glacier runoff is projected to decline globally with implications for water storage. It is estimated that Central Europe and the Caucasus have reached peak water now and that the Tibetan Plateau region will reach peak water between 2030 and 2050. The glaciers in these regions provide up to 45 per cent of the total river flow, the flow decrease would affect water availability for 1.7 billion people.
Ice sheet melt on track with ‘worst-case climate scenario’
Despite the growing push to curb emissions and reduce carbon footprint, the melting of vast ice sheets is matching with the predictions of the Intergovernmental Panel on Climate Change's (IPCC) worst-case sea-level rise scenarios.
Key findings of the report indicate that transformational action can no longer be postponed if the Paris Agreement targets are to be met. (Shutterstock)
A recent study published in Nature Climate Change concluded that the climate models created by scientists predicting the rise in sea levels match with the satellite observations from the space. An international team of scientists from the University of Leeds in the UK and the Danish Meteorological Institute (DMI) compared the ice-sheet mass-balance results from satellite observations with projections from climate models as part of the ongoing Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE).
According to the study, "Since the systematic monitoring of ice sheets began in the early 1990s, Greenland and Antarctica combined lost 6.4 trillion tonnes of ice between 1992 and 2017 – pushing global sea levels up by 17.8 millimeters." Scientists conclude that if these rates continue, ice sheets are expected to raise sea levels by a further 17 cm – exposing an additional 16 million people to annual coastal flooding by the end of this century. The new observations showed that the ice sheets are reacting surprisingly rapidly to environmental changes.
It is to be noted that climate change is affecting life-sustaining systems, from the top of the mountains to the depths of the oceans, leading to accelerating sea-level rise, with cascading effects for ecosystems and human security.