‘Nowhere to run’: 5 takeaways from the UN report on climate change, plus global reaction

The report says almost all of the warming that has occurred since pre-industrial times was caused by the release of heat-trapping gases such as carbon dioxide and methane. Much of that is the result of humans burning fossil fuels — coal, oil, wood and natural gas.

Scientists say that only a fraction of the temperature rise recorded since the 19th century can have come from natural forces.

Almost all countries have signed up to the 2015 Paris climate accord that aims to limit global warming to 2 degrees Celsius (3.6 Fahrenheit) — and ideally no more than 1.5 degrees Celsius (2.7 degrees Fahrenheit) — by the year 2100, compared to the late 19th century.

The report's 200-plus authors looked at five scenarios and concluded that all will see the world cross the 1.5-degree threshold in the 2030s — sooner than in previous predictions. Three of those scenarios will also see temperatures rise 2 degrees Celsius above the pre-industrial average.

About the photo: In this Wednesday, Feb. 17, 2021 file photo, a floating dock sits on the lakebed of the Suesca lagoon, in Suesca, Colombia. The lagoon, a popular tourist destination near Bogota that has no tributaries and depends on rain runoff, has radically decreased its water surface due to years of severe droughts in the area and the deforestation and erosion of its surroundings. 

The 3,000-plus-page report concludes that ice melt and sea level rise are already accelerating. Wild weather events — from storms to heat waves — are also expected to worsen and become more frequent.

Further warming is "locked in" due to the greenhouse gases humans have already released into the atmosphere. That means even if emissions are drastically cut, some changes will be "irreversible" for centuries, the report said.

About the photo: In this Thursday, July 29, 2021 file photo, birds fly over a man taking photos of the exposed riverbed of the Old Parana River, a tributary of the Parana River during a drought in Rosario, Argentina. Parana River Basin and its related aquifers provide potable water to close to 40 million people in South America, and according to environmentalists the falling water levels of the river are due to climate change, diminishing rainfall, deforestation and the advance of agriculture. 

While many of the report's predictions paint a grim picture of humans' impact on the planet and the consequences that will have going forward, the IPCC also found that so-called tipping points, like catastrophic ice sheet collapses and the abrupt slowdown of ocean currents, are "low likelihood," though they cannot be ruled out.

About this photo: In this Tuesday, July 20, 2021 file photok the Staten Island Ferry departs from the Manhattan terminal through a haze of smoke with the Statue of Liberty barely visible in New York. Wildfires in the American West, including one burning in Oregon that's currently the largest in the U.S., are creating hazy skies as far away as New York as the massive infernos spew smoke and ash into the air in columns up to six miles high. 

The panel is composed of independent experts put forward by governments and organizations to provide the best possible scientific consensus on climate change.

Scores of scientists provide regular reports on a range of aspects of global warming that governments draw on when discussing what countries can contribute to curb greenhouse gas emissions and adapt to the impacts of climate change.

About this photo: In this Friday, Aug. 6, 2021 file photo, smoke spreads over Parnitha mountain during a wildfire in the village of Ippokratios Politia, Greece, about 35 kilometres (21 miles), north of Athens. Thousands of people fled wildfires burning out of control in Greece and Turkey on Friday, as a protracted heat wave left forests tinder-dry and flames threatened populated areas and electricity installations. 

The report was "a code red for humanity. The alarm bells are deafening, and the evidence is irrefutable: Greenhouse gas emissions from fossil fuel burning and deforestation are choking our planet and putting billions of people at immediate risk.”

— United Nations Secretary-General Antonio Guterres

"The new IPCC report contains no real surprises. It confirms what we already know from thousands previous studies and reports — that we are in an emergency. ... It is up to us to be brave and take decisions based on the scientific evidence provided in these reports. We can still avoid the worst consequences, but not if we continue like today, and not without treating the crisis like a crisis.”

— Greta Thunberg, teenage environmental activist

“The impacts of the climate crisis, from extreme heat to wildfires to intense rainfall and flooding, will only continue to intensify unless we choose another course for ourselves and generations to come. What the world requires now is real action. All major economies must commit to aggressive climate action during this critical decade.”

— John Kerry, U.S. special presidential envoy for climate

“We know what must be done to limit global warming — consign coal to history and shift to clean energy sources, protect nature and provide climate finance for countries on the frontline.”

— British Prime Minister Boris Johnson, who is under pressure to block plans for a new coal mine in Cumbria

“The climate emergency is intensifying each day, and we in the Climate Vulnerable Forum — representing the most climate-vulnerable nations in the world — are on the front line, our nations battered by storms, droughts and rising seas."

— Mohamed Nasheed, the former president of the Maldives who now represents a group of 48 countries particularly at risk of global warming

“To those who seek to argue that it’s too hard, or too late, and so not worth trying — the report is a reminder that every fraction of a degree of warming really does matter."

— Former Irish President Mary Robinson, who chairs the independent group known as The Elders, a group of former world leaders who campaign for peace and human rights

"The report confirms in an impressive way the connection between man-made climate change and weather extremes. Floods after heavy rains, as we have just experienced, are increasing, as are heat waves and forest fires, which have plagued us in recent years.”

— German Environment Minister Svenja Schulze, whose country was last month hit by deadly flooding