World will look back at 2023 as year humanity
exposed its inability to tackle climate crisis, scientists say
Disastrous events included flash flooding in Africa
and wildfires in Europe and North America
Jonathan
Watts Global environment editor
@jonathanwatts
Fri 29 Dec
2023 14.26 GMT
The hottest
year in recorded history casts doubts on humanity’s ability to deal with a
climate crisis of its own making, senior scientists have said.
As
historically high temperatures continued to be registered in many parts of the
world in late December, the former Nasa scientist James Hansen told the
Guardian that 2023 would be remembered as the moment when failures became
apparent.
“When our
children and grandchildren look back at the history of human-made climate
change, this year and next will be seen as the turning point at which the
futility of governments in dealing with climate change was finally exposed,” he
said.
“Not only
did governments fail to stem global warming, the rate of global warming
actually accelerated.”
After what
was probably the hottest July in 120,000 years, Hansen, whose testimony to the
US Senate in 1988 is widely seen as the first high-profile revelation of global
heating, warned that the world was moving towards a “new climate frontier” with
temperatures higher than at any point over the past million years.
Now
director of the climate programme at Columbia University’s Earth Institute in
New York, Hansen said the best hope was for a generational shift of leadership.
“The bright
side of this clear dichotomy is that young people may realise that they must
take charge of their future. The turbulent status of today’s politics may
provide opportunity,” he said.
His
comments are a reflection of the dismay among experts at the enormous gulf
between scientific warnings and political action. It has taken almost 30 years
for world leaders to acknowledge that fossil fuels are to blame for the climate
crisis, yet this year’s United Nations Cop28 summit in Dubai ended with a limp
and vague call for a “transition away” from them, even as evidence grows that
the world is already heating to dangerous levels.
Scientists
are still processing data from this blistering year. The latest to state it
will be a record was the Japanese meteorological agency, which measured
temperatures in 2023 at 0.53C above the global average between 1991 and 2020.
This was
far above the previous record set in 2016, when temperatures were 0.35C above
that average. Over the longer term, the world is about 1.2C hotter than in
preindustrial times.
The US
National Oceanic and Atmospheric Administration previously calculated that
there was a “greater than 99% chance” that 2023 would be the hottest year in
its 174-year dataset. This followed six record warm months in a row, including
the northern hemisphere’s warmest summer and autumn.
Driven by
human-caused global heating and El Niño, the heat refused to relent. In
November, there was an even greater anomaly, with two days warmer than 2C above
the preindustrial average, according to Europe’s Copernicus Climate Change
Service.
It too has
already confirmed the annual record, as has the World Meteorological
Organization. In December, many parts of the world sweltered through the
hottest-ever Christmas. With the new year approaching, monthly temperature
records were still being beaten in central Asia, South America, Europe and
Australia.
Berkeley
Earth has predicted that average temperatures in 2023 will almost certainly
prove to have been 1.5C higher than preindustrial levels. Although climate
trends are based on decadal rather than annual measurements, many scientists
say it is probably only a matter of time before the world overshoots the most
ambitious of the Paris agreement targets.
Veteran
climate watchers have been horrified at the pace of change. “The climate year
2023 is nothing but shocking, in terms of the strength of climate occurrences,
from heatwaves, droughts, floods and fires, to rate of ice melt and temperature
anomalies particularly in the ocean,” Prof Johan Rockström, the joint director
of the Potsdam Institute for Climate Impact Research in Germany, said.
He said
these new developments indicated the Earth was in uncharted territory and
under siege. “What we mean by this is that we may be seeing a shift in Earth’s
response to 250 years of escalated human pressures … to a situation of
‘payback’ where Earth starts sending invoices back to the thin layer on Earth
where humans live, in the form of off the charts extremes.”
Rockstrom
was among the authors of the 2018 “Hothouse Earth” paper, which warned of a
domino-like cascade of melting ice, warming seas and dying forests could tilt
the planet into a state beyond which human efforts to reduce emissions will be
increasingly futile.
Five years
on, he said that what disturbed him most in 2023 was the sharp increase in sea
surface temperatures, which have been abrupt even for an El Niño year.
“We do not
understand why the ocean heat increase is so dramatic, and we do not know what
the consequences are in the future,” he said. “Are we seeing the first signs of
a state shift? Or is it [a] freak outlier?”
In the
Antarctic, scientists have also been perplexed and worried by the pace of
change. The new Brazilian scientific module Criosfera 2, a solar and
wind-powered laboratory that collects meteorological information, measured the
lowest extent of sea ice in the region both for summer and winter.
“This
environmental alert is a sign of ongoing global environmental changes and poses
a daunting challenge for polar scientists to explain,” said Francisco Eliseu
Aquino, a professor of climatology and oceanography at the Federal University
of Rio Grande do Sul and the deputy director of Brazil’s polar and climatic
centre.
West
Antarctica was affected by several winter heatwaves associated with the
landfall of atmospheric rivers. In early July, a Chilean team on King George
Island, at the northern tip of the Antarctic peninsula, registered an
unprecedented event of rainfall in the middle of the austral winter when only
snowfalls are expected.
In January,
a massive iceberg, measuring about 1,500 sq km, broke off from the Brunt ice
shelf in the Weddell Sea. It was the third colossal calving in the same region
in three years.
Aquino said
human influence – through the burning of fossil fuels – had also created
“frightening” dynamics between the poles and the tropics. Cold wet fronts from
the Antarctic had interacted with record heat and drought in the Amazon to
create unprecedented storms in between. Floods in southern Brazil killed 51
people in early September and then returned with similarly devastating force in
mid-November.
Aquino said
this “record record” was a taste of what was to come as the world entered
dangerous levels of warming. “From this year onwards, we will understand
concretely what it means to flirt with 1.5C [of heating] in the global average
temperature and new records for disasters,” he said.
This is
already happening. This year’s deadliest climate disaster was the flood in
Libya that killed more than 11,300 people in the coastal city of Derna. In a
single day, Storm Daniel unleashed 200 times as much rain as usually falls on
the city in the entire month of September. Human-induced climate change made
this up to 50 times more likely.
Forest
fires burned a record area in Canada and Europe, and killed about 100 people in
Lahaina on Maui island, the deadliest wildfire in US history, which happened in
August. For those who prefer to calculate catastrophe in economic terms, the US
broke its annual record of billion-dollar disasters by August, by which time
there had already been 23.
Raul
Cordero, a climate professor at the University of Groningen and the University
of Santiago, said the effects of this year’s heat were being felt across South
America in the form of unprecedented water stress in Uruguay, record-breaking
fires in Chile, the most severe drought in the Amazon basin in 50 years,
prolonged power shortages in Ecuador caused by the lack of hydropower, and
increased shipping costs along the Panama canal due to low water levels.
Cordero
said El Niño was forecast to weaken in the coming year, but above average or
record temperatures were likely to persist for at least the next three months.
And, as
science has proved beyond any doubt, global temperatures would continue to rise
as long as humanity continues to burn fossil fuels and forests.
In the
years ahead, the heat “anomaly” and catastrophes of 2023 would first become the
new norm, and then be looked back on as one of the cooler, more stable years in
people’s lives. As Hansen warned, unless there is radical and rapid change,
failure will be built into the climate system.
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