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‘Climate change poses risks for human and natural systems’: Key quotes from the IPCC’s Working Group 2 report

  • 01 Apr 2014, 11:55
  • Roz Pidcock & Mat Hope

The Intergovernmental Panel on Climate Change released a big report on the impacts of climate change yesterday. The report looked at everything from how climate change puts species and societies at risk, to what rising emissions may mean for marine life and extreme weather events.

We pick out some key quotes from the IPCC's Working Group 2 Summary for Policymakers.

Impacts of climate change

"Human interference with the climate system is occurring, and climate change poses risks for human and natural systems"

"In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans."

"Some risks of climate change are considerable at 1 or 2°C above preindustrial level. Global climate change risks are high to very high with global mean temperature increase of 4°C or more ... and include severe and widespread impacts on unique and threatened systems, substantial species extinction, large risks to global and regional food security"

"Climate-change impacts are expected to exacerbate poverty in most developing countries and create new poverty pockets in countries with increasing inequality, in both developed and developing countries."

Food production & security

"All aspects of food security are potentially affected by climate change, including food access, utilization, and price stability (high confidence)."

"Based on many studies covering a wide range of regions and crops, negative impacts of climate change on crop yields have been more common than positive impacts (high confidence)."

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The IPCC's report on the impacts of climate change: a summary for everyone

  • 31 Mar 2014, 13:30
  • Ros Donald

Peter Blanchard/Flickr

Today an international group of hundreds of  climate scientists released a report on how climate change will affect the world, and what might be done to adapt to it.

The story so far

The report from the Intergovernmental Panel on Climate Change (IPCC) is the second of three reports. It updates the panel's last bumper report, released in 2007.

Scientists know that carbon dioxide is a greenhouse gas, meaning it traps heat in the atmosphere and oceans.

Over time, scientists have come to understand more about how gases like carbon dioxide, emitted when people burn fossil fuels like oil and gas, affect the climate.  

The first instalment of the IPCC's report, released last September, says scientists are more sure than ever - 95 per cent certain - that humans are causing extra warming. And as a result, oceans, land and atmosphere are getting warmer, snow and ice is melting and sea levels are rising.

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Big impacts: The main messages from today’s big UN climate report

  • 31 Mar 2014, 12:30
  • Roz Pidcock

A landmark new report on climate change came out earlier today, looking at the impact of past and future warming on ecosystems and human society. Here's our rundown of the report's main messages, on everything from fisheries to flooding.

We're already feeling the impacts of climate change

That the planet is warming is not in doubt. Global temperature has risen by  0.85 degrees  over the industrial period (1880 to date). We're already seeing the impacts of this amount of warming over much of the land and oceans.

The Summary for Policymakers ( SPM) says some risks of climate change are considerable at 1 or 2°C above preindustrial levels and that further warming will "increase the likelihood of severe, pervasive, and irreversible impacts."

Greater confidence in the extent and pace of climate change since the last assessment report comes from having more data and new ways of analysing earlier measurements.

Our weather will get more extreme

Climate change is already leading to more hot days and nights and fewer cold days and nights. Heatwaves have become more common and more intense in the last half century.

In general, wet places are set to get wetter, and dry places to get drier. Some parts of the world are already seeing more frequent and more serious drought, leading to a reduction in water availability.

In other regions, changing rainfall patterns and melting glaciers are altering river flow, causing a rise in flooding. The SPM says:

"The fraction of global population experiencing water scarcity and the fraction affected by major river floods increase with the level of warming in the 21st century."

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Carbon briefing: changing views on biofuels reflected in forthcoming climate report

  • 26 Mar 2014, 11:15
  • Robin Webster

The Intergovernmental Panel on Climate Change (IPCC)'s new report, due to be launched next week, is likely to give a new and updated perspective on biofuels - reflecting a flood of research on their impact on natural systems in past years. 

The UN-created body launched its last major report back in 2007. At that time, the idea of using plant based crops as a replacement for fossil fuels was largely viewed as an effective way of reducing greenhouse gas emissions from the transport sector. 

But soon afterstudies began emerging in the scientific literature that challenged this idea. They suggested biofuels could damage the environment, drive up  food prices, or even increase  greenhouse gas emissions

Biofuels in the the IPCC's Fourth Assessment

Back in 2007, the IPCC  identified transport biofuels as a "key mitigation strategy". They "might" play an important role in addressing greenhouse gas emissions in the transport sector, it said. 

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A big UN report on climate change impacts is coming: how is it being reported?

  • 24 Mar 2014, 17:00
  • Roz Pidcock

Hundreds of governments will convene in Japan tomorrow to discuss a new major UN climate change report. From slowing economic growth to species extinctions to food insecurity, the report reviews climate change's wide-ranging impacts on humans and the environment.

Last September, the Intergovernmental Panel on Climate Change (IPCC) released the  first part of the report. It covered the physical science, from extreme rainfall to Arctic ice melt.

Ahead of its official launch on Monday, parts of the media have been previewing the second part of the report on climate change impacts, after it was leaked online a few months ago.

Here's our rundown of which of what's been making the pages of our newspapers;

"Immediate and very human" risks

Seth Borenstein for Associated Press gives a succinct rundown of the "immediate and very human' nature of climate change impacts. On the report's key messages, Borenstein says:

"The big risks and overall effects of global warming are far more immediate and local than scientists once thought. It's not just about melting ice, threatened animals and plants. It's about the human problems of hunger, disease, drought, flooding, refugees and war, becoming worse."

Alister Doyle for  Reuters describes how climate change impacts are already being felt across the world, putting pressure on governments to act. Growing risks include food and water security, violence and conflict, health risks, species losses, extreme weather and slowed economic growth.  

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Scientists respond to “misleading” Times article about climate change’s impact on crop yields

  • 21 Mar 2014, 12:35
  • Roz Pidcock

The authors of a new paper on how climate change could affect crop yields in the future have reacted to an article in the Times yesterday, calling the headline "very misleading".

The Times piece suggested the new research shows climate change will boost crop yields, a conclusion the newspaper said is "at odds" with the mainstream scientific view. But this interpretation is "fabricating controversy where none actually exists", the authors tell us.

Extreme heat

The  new study is the first to quantify the effect of future heatwaves on food production. The latest report from the Intergovernmental Panel on Climate Change (IPCC)  concluded it is very likely heatwaves will get longer and more frequent this century.

Until now, studies have only looked at what effect the rise in the global average temperature might have on crops.

Writing in the journal Environmental Research Letters, the authors looked at how the extra impact of heat waves will affect yields of three major crops - maize, spring wheat and soybean.

Crops, heatwaves and carbon dioxide

Heat waves have a negative impact on all three crops, with maize suffering the biggest losses, the researchers found. Their findings show heatwaves could double maize losses by the 2080s, compared to the 1980s.

As well as temperature, the researchers took into account how rising carbon dioxide in the atmosphere could influence crop growth.  Experiments have shown that raising carbon dioxide levels could make plants more efficient at using water, boosting growth.

The new paper's calculations included the possibility that this 'carbon dioxide fertilisation' effect could counteract some of the losses that come from higher temperatures and heatwaves.

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Heatproofing London: Climate change raises city heat death risk, but adaptation can cut the impact

  • 20 Mar 2014, 12:30
  • Ros Donald

Heatwaves have an amplified impact in cities, causing disproportionate discomfort, health risks and mortality rates - an effect that's expected to worsen as temperatures rise, according to new research. But the scientists also find taking measures to adapt cities to higher temperatures can reduce heat-related deaths by between 32 and 69 per cent.

The Intergovernmental Panel on Climate Change (IPCC)'s projections of future climate change suggest it's likely heatwaves may become longer and/or more frequent by the end of the century. That's expected to make baking city summers even more unbearable.

Relatively little research has been done to find out how effective attempts to adapt to hotter temperatures will be.

In the new study, researchers from a group of UK universities set out to give a risk assessment of how higher temperatures will affect city-dwellers - examining projections of urban temperatures into the future, as well as predictions of how populations will change.

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Scientists challenge climate skeptic claims that UN panel overestimates warming

  • 06 Mar 2014, 14:30
  • Roz Pidcock

Lord Lawson's skeptic lobby group, the Global Warming Policy Foundation (GWPF), released a report today criticising scientists' estimate of how sensitive earth's climate is to carbon dioxide.

In what may be a sign of growing confidence in the scientific community about engaging online, climate scientists have been quick to respond, highlighting what they label the report's "cherry picking" approach.

They have also pointed out Lawson's lobby group appears to have unwittingly come out in support of the mainstream scientific view - that we can expect a serious level of warming if emissions aren't brought down swiftly.

The GWPF  report, entitled 'Oversensitive: How the IPCC hid good the news on global warming", argues the UN's official climate body glossed over the possibility of modest future warming in its  latest assessment, in favour of evidence that the risks could be much higher.

Authored by former financier Nic Lewis, who describes himself as an "independent climate scientist", and freelance science writer Marcel Crok, the report claims to provide a "technically sound" and "independent" assessment of the IPCC's conclusions.

But climate scientists strongly disagree, today pointing out issues with the analysis.

A matter of sensitivity

The new GWPF report centres on something called climate sensitivity - the warming we can expect when carbon dioxide concentration reaches double what it was in preindustrial times.

In its most recent report, the IPCC estimated we're likely to see between one and 2.5 degrees Celsius at the point of doubling. This is what's known as the Transient Climate Sensitivity ( TCR).

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Cut the 'weirdo words' and put a human face on climate change, says UN chief

  • 06 Mar 2014, 12:00
  • Ros Donald

Scientists are making a huge effort to translate and humanise climate change - and cut out "weirdo words" the public and policymakers can't understand, the UN's chief climate official said yesterday.

Christiana Figueres told reporters that the UNFCCC, the body dedicated to reaching a global deal on climate change, needs to prioritise getting better at communication. But the way she tells it, there's a revolution going on.

Many of those involved in the UN climate talks, and the production of the bumper science reports from the Intergovernmental Panel on Climate Change (IPCC) have "reached the conclusion that we're just not communicating properly" she told journalists yesterday.

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Special reflection: How scientists, media and the public see the surface warming ‘pause’

  • 26 Feb 2014, 17:45
  • Roz Pidcock

A prestigious journal has released a special issue on what's become something of a preoccupation in the crossover between science and mainstream media recently - an apparent slowdown in surface warming over the last decade or so.

Nature Climate Change dedicates a  whole issue to the so called 'pause' - looking at how scientists, the public and the media have been talking about it.

The issue talks a lot about lessons for scientists in engaging with the media, but is it worth so much soul-searching when evidence suggests the 'pause' has barely made a ripple in the public consciousness?

A lively debate

Since the late 1990s, global average temperature at earth's surface has risen slower than in the preceding two decades. The Intergovernmental Panel on Climate Change (IPCC)'s recent  report said the rate of warming over the past 15 years has been 0.05 degrees Celsius per decade - quite a bit smaller than the 0.12 degrees per decade calculated since 1951.

The apparent slowdown is a hot topic, and not just in the science world. Evidence of the 'pause' in surface warming "has sparked a lively scientific and public debate", says the Nature Climate Change   editorial.

Media pickup

An early outing for the 'pause' as a concept was an op-ed in the Telegraph in 2006. The piece claimed global warming had "stopped", triggering a   series of   articles in parts of the media since then.

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