Climate science

UK flooding pushes public acceptance of manmade climate change to five-year high

  • 29 Jan 2015, 00:01
  • Robert McSweeney

There is growing public acceptance of the human contribution to climate change, according to a new study published today. The latest results from a national survey show public agreement that humans are causing climate change is at its highest level for 5 years.

The researchers also find that those affected by the UK winter floods in 2013-14 were significantly more likely to be concerned about climate change than those that weren't affected.

Public acceptance

A year on from the major winter flooding in the UK, the new study led by Cardiff University sheds new light on public perception of climate change. Researchers interviewed 1,002 people across the country about their views on climate change and the floods.

The results of the survey show almost nine in 10 respondents said the world's climate is changing (88 per cent), and more than eight in 10 said human activity was at least partly the cause (84 per cent). This represents the highest level of acceptance that the climate is changing since surveys began asking the question in 2005. More than a third (36 per cent) said that climate change is mainly or entirely caused by humans, which is the most agreement on the human impact on climate change since the question was first included in comparative surveys in 2010.

Capstick Et Al (2015) Is The Climate Changing

Responses from this and previous surveys to the question 'As far as you know, do you personally think the world's climate is changing?'. Source: Capstick et al. (2015).

Capstick Et Al (2015) Causes Of Climate Change

Responses from this and previous surveys to the question 'Thinking of the causes of climate change, which best described your opinion?'. Source: Capstick et al. (2015).

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Warming Arctic to break down barriers between Atlantic and Pacific fish, study finds

  • 27 Jan 2015, 16:23
  • Robert McSweeney

For millions of years, fish species in the Pacific and Atlantic oceans have stuck resolutely to where they belong, kept from venturing between oceans by the cold water of the Arctic.

But new research suggests a warming Arctic could soon see fish putting aside their differences and bridging this chilly divide. And this could have implications for native species and commercial fisheries, the researchers say.

A natural barrier

For most of the last 2.6 million years, the cold temperatures and low nutrient levels of the Arctic have deterred fish species from crossing between the Pacific and Atlantic oceans.

The cold conditions mean at present only 135 of more than 800 known fish species are found in latitudes north of where the UK sits, in either the Atlantic or Pacific Ocean.

But a new study, published in Nature Climate Change, finds that with Arctic temperatures increasing almost twice as fast as the global average, this natural barrier is set to weaken.

Melting sea ice will mean ocean currents can carry warmer water and nutrients into Arctic water, taking fish further north and potentially allowing them to mix between oceans.

'Rapid explosion in fish biodiversity'

The researchers use computer models to forecast future ocean conditions such as surface temperatures, salinity, and currents, and project how the distribution of different fish species could respond to climate change.

They analysed how suitable the Arctic seas would be for over 500 fish species during this century if greenhouse gas emissions continue at current rates.

The maps below show that many species will gradually progress north, eventually reaching the northern coasts of Canada and Russia, where fish from each ocean can mix. Their modelling shows that by 2100, 44 species could enter the Atlantic from the Pacific, with 41 species potentially crossing back the other way.

Wisz Et Al . (2015) Fig 1 Fish Interchange

Projected number of fish species in high latitudes under business-as-usual greenhouse gas emissions. Results shown for 2015, 2050 and 2100. The dark blue show areas with the most species present. Source: Wisz et al. (2015).

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Expect twice as many extreme La Niña events under climate change, study warns

  • 26 Jan 2015, 16:00
  • Robert McSweeney

The Pacific weather phenomenon known as El Niño or 'The Little Boy' is regularly in the news. Scientists keep a close eye on its status as events can cause devastating extreme weather around the world.

But El Niño has a lesser-known sister, La Niña, which also has a dramatic impact on global weather. Now a new study suggests that we could see La Niña events occurring twice as often as the climate warms.

The lesser-known sibling

Every five years or so, weakening trade winds causes a shift to warmer than normal ocean temperatures in the eastern equatorial Pacific Ocean, a phenomena known as El Niño.

La Niña, or 'The Little Girl', is El Niño's cold water counterpart. During La Niña events the trade winds strengthen, and the central and eastern Pacific Ocean becomes even colder than normal. La Niñas are known to bring drought to the southwestern US, floods to Central America, and hurricanes to the Atlantic Ocean.

Together, the warm and cold events form the El Niño-Southern Oscillation (ENSO), and cause most of the fluctuations in global weather we see from one year to the next.

Understanding how extreme La Niña will change as global temperatures rise has challenged scientists for the past three decades. A new paper, published in Nature Climate Change, suggests that extreme La Niña events will occur almost twice as often in the twenty-first century than they did in the twentieth.

La -nina

Credit: Rosamund Pearce, Carbon Brief

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