Geneva, May 18
Greenhouse gas concentrations, sea level rise, ocean heat and ocean acidification — the four key climate change indicators — set new records in 2021 with extreme weather — the day-to-day 'face' of climate change — led to hundreds of billions of dollars in economic losses, the WMO State of the Global Climate in 2021 report said on Wednesday.
"It wreaked a heavy toll on human lives and well-being and triggered shocks for food and water security and displacement that have accentuated in 2022. This is yet another clear sign that human activities are causing planetary scale changes on land, in the ocean, and in the atmosphere, with harmful and long-lasting ramifications for sustainable development and ecosystems," the World Meteorological Organisation (WMO) said.
Global annual mean temperature difference is considered from pre-industrial conditions (1850-1900) for six global temperature data sets (1850-2021).
The WMO State of the Global Climate in 2021 report confirmed that the past seven years have been the warmest seven years on record and that year 2021 was "only" one of the seven warmest because of a La Nina event (ocean phenomenon in the Pacifics) at the start and end of the year. "This had a temporary cooling effect, but did not reverse the overall trend of rising temperatures. The average global temperature in 2021 was about 1.11 (plus/minus 0.13) degrees Celsius above the pre-industrial level.
"It is just a matter of time before we see another warmest year on record," said WMO Secretary-General Professor Petteri Taalas. "The heat trapped by human-induced greenhouse gases will warm the planet for many generations to come. Sea level rise, ocean heat and acidification will continue for hundreds of years unless means to remove carbon from the atmosphere are invented. Some glaciers have reached the point of no-return, and this will have long-term repercussions in a world, in which more than 2 billion people already experience water stress."
The report's key findings include record high ocean heat — much of the ocean experienced at least one 'strong' marine heatwave at some point in 2021; ocean acidification findings reiterated the Intergovernmental Panel on Climate Change (IPCC) conclusions that open ocean surface pH is now the lowest it has been for at least 26,000 years and current rates of pH change are unprecedented; global mean sea level reached a new record high in 2021, after increasing at an average 4.5 mm per year over the period 2013 -2021, which is more than double the rate between 1993 and 2002 and is mainly due to the accelerated loss of ice mass from the ice sheets and in case of cryosphere, the glaciological year 2020-2021 saw less melting than in recent years, but there is a clear trend towards an acceleration of mass loss on multi-decadal timescales.
The report also speaks of exceptional heat waves droughts, ozone hole over the Antarctic, famine, and internal displacement.
"Extreme weather has the most immediate impact on our daily lives. Years of investment in disaster preparedness means that we are better at saving lives, though economic losses are soaring. But much more needs to be done, as we are seeing with the drought emergency unfolding in the Horn of Africa, the recent deadly flooding in South Africa and the extreme heat in India and Pakistan," Taalas said.
"Early Warning Systems are critically required for climate adaptation, and yet these are only available in less than half of WMO's members. We are committed to making early warnings reach everyone in the next five years, as requested by the United Nations Secretary-General Antonio Guterres," he said.
The WMO State of the Global Climate report complements the IPCC Sixth Assessment report, which includes data up to 2019. The new WMO report provides information and practical examples for policy-makers on how the climate change indicators outlined in the IPCC reports played out during the recent years globally and how the associated implications on extremes have been felt at national and regional level in 2021.