Tag Archives: tipping points

Will the IPCC finally come to terms with climate risk?

The IPCC Intergovernmental Panel on Climate Change) is planning to release the first of four reports in its 6th Assessment Report (6AR) on Monday, 9 August, 2021.

I believe the largest question will be whether the IPCC, this time, adequately accounts for risk. Continue reading Will the IPCC finally come to terms with climate risk?

The fierce urgency of now: ie 2009…2021…?

Back in May 2009 some 60 Nobel Prize winners, some of the best minds on the planet, meeting as the St James’s Palace Nobel Laureate Symposium issued a memorandum under the call of The Fierce Urgency of Now:

    calling on world leaders for a global deal on climate change that matches the scale and urgency of the human, ecological and economic crises facing the world today. [ie, May 2009]

Continue reading The fierce urgency of now: ie 2009…2021…?

Climate tipping points: real and present

The planet has changed. This is Iceland’s Skaftafellsjokull glacier in 1989 and 2020:

As reported in Al Jazeera, Christiana Figueres, one of the architects of the Paris Agreement, was stunned speechless when:

    She was told by leading climate scientist Johan Rockström, the director of the Potsdam Institute for Climate Impact Research, that we have already gone beyond some key tipping points. Losing the resilience of the planet was the nightmare that is keeping scientists awake at night, Rockström said.

He was referring to (1) the Arctic summer sea ice (2) West Antarctic glaciers, and (3) tropical coral reef systems. Continue reading Climate tipping points: real and present

Our beds are burning

Ask yourself a simple question. Can you give hope to future generations that the Great Barrier Reef will be protected if your policy is to limit warming to 1.5°C when the GBR is already disappearing before our eyes?

With about 1.1°C of warming we are told that Unprecedented fires in California and Australia signal the dawn of the ‘fire age’. Richard Flanagan talks of a Tasmanian rainforest burnt in 2018, now desolate shale with no sign of regrowth.

As I write, pristine Fraser Island is burning on a front about 46 km long, with reports that water from water bombers is evaporating before it hits the ground.

We have now reached a point where the cost of insurance alone in flood and bushfire-prone communities makes it impossible to live there.

Dangerous climate change is already here.

How can we set a target of 1.5°C temperature (actually a 50% chance of limiting the increase to that level) when we know that during the Eemian interglacial sea levels rose 6-9 metres with 300ppm of CO2, and we have already broken through the 410 ppm? Continue reading Our beds are burning

Has the climate tipped?

‘Tipping point’ is a metaphor, first used by science and the media about climate change from about 2005 as this article explains. The metaphor has become topical now because some of the most senior climate scientists on the planet have used it to warn everyone, just before the nations of the world meet in the Conference of Parties of the UNFCCC meet in the first two weeks of December, as they do every year, this time in Madrid, to plan an international response to what was identified in the Rio Earth Summit as dangerous anthropogenic interference [DAI] with the climate system”.

The article, commentary rather than research – Climate tipping points — too risky to bet against – is freely available at Nature. The authors are Timothy M. Lenton, Johan Rockström, Owen Gaffney, Stefan Rahmstorf, Katherine Richardson, Will Steffen and Hans Joachim Schellnhuber with the message;

    The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions.

Continue reading Has the climate tipped?

Cloud tipping point could yield a cataclysmic 14°C warming

Clouds could trigger a feedback effect. Stocktrek Images, Inc. / Alamy Stock Photo

Commonly 2°C has been seen as the threshold for dangerous climate change, although last year the IPCC report on 1.5°C revealed that at that lower level we enter a zone where tipping points may take us to 4°C and beyond.

Levels of 4°C threaten civilisation as we know it. At 6°C we worry about the survival of the human race. However, at that point Tapio Schneider and his team at the California Institute of Technology, Pasadena, have found that there may be a further tipping point which heats the planet another 8°C to make it 14°C above pre-industrial levels (New Scientist, so probably pay-walled.)

How is this so? Continue reading Cloud tipping point could yield a cataclysmic 14°C warming

Trouble at the top of the world

Arctic summer sea ice minimum was the sixth lowest on record. So we can all relax, right?

Wrong.

I’ll come back to that. However, Tamino at Open Mind points out that while the Arctic warms three to four times as fast as global warming, the Arctic winters are warming at a much faster rate.

Using the NASA data, which is about mid-range in the major players, Tamino finds that the overall average warming rate since 1985 in the Arctic, at 6.48°C/century is fully 3.4 times as fast as the global rate since 1985 of 1.90°C/century. Continue reading Trouble at the top of the world

Science shows the need for urgent climate action

In August last year in Climate clippings 181 (Item 5) I linked to a report by Climate Analytics examining the impacts on Australia of limiting global temperature rise to 1.5°C and 2°C.

For me the crux of the report is this, from a discussion piece at The Conversation:

    The report predicts that half of the world’s identified tipping points – such as the collapse of polar ice sheets and the drying out of the Amazon rainforest – would be crossed under 2C warming, compared with 20% of them at 1.5℃.

If we go to 2℃, we will have a very different climate and there is a good chance we won’t be able to stabilise there. The bad news is that if we just carry on we’ll reach 1.5C by 2024, and 2C by 2036. Continue reading Science shows the need for urgent climate action

Tipping point for climate action?

Recently the Climate Commission issued a report in its The Critical Decade series on Extreme Weather looking at the issues of

  • Heat
  • Bushfires
  • Rainfall
  • Drought, and
  • Sea level rise.

At Radio National’s The World Today Professor Lesley Hughes, a Macquarie University ecologist, talked to Eleanor Hall.

The report looks at extreme weather experience in recent times, such as that documented in the Commission’s report The Angry Summer, puts it in a broader context using the latest science and then uses that as a window to project into the future. The message is plain. The climate has shifted, expect more and more extreme weather and we need to act now.

we really need to view all these events not in isolation but as part of a trend for the future. We need to prepare for them and we need to do our absolute best to cut greenhouse gases to stabilise the climate to prevent them getting to the point at which we cannot adapt.(Emphasis added)

Continue reading Tipping point for climate action?

Climate clippings 39

Greenland ice

Predicting tipping points

Tim Lenton is now attempting to link the basic theory of climatic “tipping points” with observed early warning signals.

Problem is, these tipping points may not be sudden and dramatic but involve a steady but inevitable increase. When outbreaks of pine beetles first became obvious perhaps the eventual destruction of Canada’s boreal forests was inevitable. But Lenton is making an argument “from almost a mathematical point of view” that there are general properties of tipping points. Continue reading Climate clippings 39

Climate clippings 15

These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.

They can also serve as an open thread so that we can keep each other informed on important climate news.

Beware the collapse of the planet’s lungs

Amazon drought is consistent with what scientific models predict for a warmer globe.

Normally, rainforests function like great carbon sinks, absorbing a large proportion of the CO2 that human activity produces. But in 2005, thanks to deforestation, the Amazon became a net emitter of carbon dioxide. In that year, the rainforest is estimated to have emitted some 5 billion tonnes of CO2, almost as much as the entire output of the United States.

Continue reading Climate clippings 15