The state of the climate in 2023 (2023)

This week, the UN's climate science body releases a major report on climate change occurring around the world due to human activity.

In its last report for 2021, the Intergovernmental Panel on Climate Change (IPCC) warned thatHuman activity is changing the climate in unprecedented waysand sometimes irreversible. Scientists said drastic reductions in emissions are needed this decade to keep global warming below 1.5°C and protect the world's most vulnerable ecosystems and communities.

This latest report is likely to "underline that time is running out for easier solutions and more gradual transitions to a carbon-free economy," says Bonnie Waring, Grantham Institute Senior Lecturer in Climate Change and Environment at Imperial College London.

In recent years, the world has experienceddevastating extreme weather caused by climate change,record temperatureyrapid melting of ice. Scientists are now tracking the state of the climate more than ever before. Here are five key indicators to gauge your health in 2023.

CO2 atmospheric levels

The amount of CO2 in the atmosphere this year is expected to be419.2parts per million (ppm), according to theMauna Loa Observatory in Hawaii.The world average last year was417,2 ppm.

Over the past 50 years, we've added 100 ppm of CO2 to the atmosphere, according to Martin Siegert, co-director of the Grantham Institute. "It's going up about two points every year, so in 100 years we'd end up at 600 ppm and that would be crazy," he says.

The last time CO2 levels exceeded 400 ppm was aroundfour million years ago, during the Pliocene era, when global temperatures were 2 to 4 °C (3.6 to 7.2 °F) warmer and sea levels were 10 to 25 m (33 to 82 ft) higher than nowadays.

"Atmospheric CO2 levels continue to rise. This is a big problem because we are getting dangerously close to a future where we won't be able to keep [global] warming below 1.5°C," says Waring.

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Last yearthe IPCC warnedwhat to removeCO2of the atmosphere is essential because even deep cuts in emissions will not be enough to limit global warming. "It puts us in a very dangerous situation because we have very few scalable strategies to do this," says Waring. Technologies to capture and store CO2 are still emerging, very expensive and unproven. (read more aboutplans to extract CO2 from the air).

“It's absolutely the worst case scenario that we need to do this because other things have failed,” says Siegert, adding that there is no “magic bullet” for dealing with climate change. "We can't put everything on carbon capture."

forest loss

Planting more trees and protecting ecosystems that absorb carbon is one of the most effective ways to increase carbon sequestration. But forests all over the world areshrinking at an alarming rate. According to new research, the destruction of tropical forests isfar exceeding the current rate of growth.

This is affecting how much carbon rainforests hold. HeyouForest carbon loss in the tropics doubledin 2015-2019 as it was in 2001-2005, according to a 2022 study.

A quarter of the Amazon rainforest now emits more carbon than it absorbs as a result of deforestation and drier conditions (Credit: Mauro Pimentel/Getty Images)

heat record

2022 was the sixth warmest yearsince records began in 1880. The oceans have beenthe hottest on record in 2022. The 10 warmest years on record have occurred since 2010.

A total of 28 countries experiencedits hottest year on record in 2022, including the United Kingdom, China and New Zealand.

Record temperatures often coincide with aEl Niño event (a large band of warm water that forms in the Pacific Ocean every few years), but last year there was a La Niña event (the opposite of El Niño, when a band of colder water forms). Without the La Niña temperature drop, 2022 would have been much warmer.

"You don't need the hottest year globally to experience the hottest weather [in some places]," says Siegert, pointing to record heatwaves in countries likeEuropa,IndiayPorcelain. According toscientists from World Weather Attribution, an independent research institute, climate change has played a clear role in increasing the likelihood of all these events.

melt ice

Arctic sea ice has shrunklowest fifth ever recorded, retreating to 14.62 million square kilometers (5.64 million square miles). "In general, we have thinner ice than we used to have... which leads to less ice in late summer," says Julienne Stroeve, a polar scientist at University College. London.

The rapid loss of sea ice in the Arctic is not just a symptom of climate change, it's also a factor. is decreasing thealbedo effect, which is the ability of snow and ice to reflect heat. "It's a runaway feedback process," says Siegert. "As the ice begins to retreat, the white reflective surface is replaced by a dark surface that absorbs heat, leading to greater sea ice loss."

now there isless sea ice around Antarcticathan at any time since satellites began measuring it in the late 1970s.

The US National Snow and Ice Data Center said stronger-than-average winds combined with warmer ocean and air temperatures reduced coverage to just1.91 million square kilometers (737,000 square miles) on February 13.

This was a new historic low and only the second year that Antarctic sea ice cover has fallen below two million square kilometers (772,000 square miles). The previous record of 1.92 million square kilometers (741,000 square miles) was reached on February 25 last year.

There is now less sea ice around Antarctica than at any time since satellites began measuring it in the late 1970s (Credit: David Tipling/Getty Images)

But what is really worrying is the melting of the Antarctic ice sheets, because it could lead to a dangerous rise in sea levels, says Siegert.

Antarctica is losing ice mass at a rate of150 billion tons per year. The East Antarctic ice sheet could lead to aestimated 52 m (170 ft) potential sea level rise, compared to the West Antarctic ice sheet, which may result in3-4 m (10-13 twists). (read more aboutWhy is East Antarctica a "sleeping giant" of sea level rise?).

"Over the last few thousand years, it's always been the ocean temperature [which causes water to expand] that has caused the sea level to rise by centimeters. But now it's the ice sheets and they're not talking about centimeters, they're talking about meters", says Siegert.

permafrost thawing

Across the northern hemisphere, permafrost, ground that remains frozen year-round for two years or more, is also rapidly warming.

“From observation networks, we see clear warming in permafrost areas,” says Stroeve. This is concerning because permafrost contains a large amount of greenhouse gases, including CO2 and methane, which are released into the atmosphere during melting.

"Since current carbon storage in permafrost is estimated at more thandouble [the amount] in our atmosphere, this is worrying as overall global warming will increase," says Stroeve.

Soils in the permafrost region, which covers 23 million square kilometers (8.9 million square miles) in Siberia, Greenland, Canada and the Arctic, contain nearly1,700 trillion tons of carbon.

Melting permafrost could also damage existing infrastructure and affect the livelihoods of indigenous communities, who rely on the frozen ground to travel and hunt on the edge of sea ice. (read more aboutInuit knowledge disappearing with the ice).

The current state of the climate highlights "why it's so important that we take this seriously now," says Siegert. "We can do something about climate change now and recognize that if we don't, things will only get worse for the people who come after us."

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