Climate science

Widespread methane leakage found on US Atlantic coast

  • 26 Aug 2014, 15:39
  • Robert McSweeney

New research has found evidence of methane leaking from under the sea floor on the Atlantic Coast of the US. Could this be the beginnings of a huge release of methane into our atmosphere? Scientists tell us probably not.

Seabed seeps

The research has identified hundreds of 'seeps' along the American Atlantic coast - places where gas bubbles out of the sea floor. This could be just the beginning, with perhaps "tens of thousands" more seeps to discover, the researchers say.

They also say it's likely the bubbling gases include methane - a powerful but short-lived greenhouse gas. Methane stored under the seabed is one of the largest reserves of methane on the planet - a companion article describes the overall size of the reservoir as "staggering".

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Pacific watch: Is El Niño finding its second wind?

  • 22 Aug 2014, 14:55
  • Roz Pidcock

Scientists around the world have been watching closely to see if an El Niño develops this year - a weather phenomenon in the Pacific that drives extreme weather worldwide.

After initially predicting with  90 per cent certainty we'd see an El Niño by the end of the year, forecasters began scaling back their predictions earlier this month.

But interest in the Pacific weather phenomenon shows no sign of waning. And after much talk of El Niño cooling off, there are hints it could be rebounding, say scientists.

El Niño watch

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

Together, El Niño and its cooler counterpart La Niña are known as the El Niño Southern Oscillation (ENSO). Between them, they're responsible for most of the fluctuations in global temperature and rainfall we see from one year to the next.

Earlier this year, the ocean looked to be primed for an El Niño, with above average temperatures in the eastern Pacific lasting throughout March and May.

But last month, forecasters across the world began  dialling down their forecasts. The atmosphere had "largely failed to respond" to sea surface temperatures, scientists announced.

"Waiting for Godot"

This week, the US National Oceanic and Atmospheric Administration (NOAA)  dropped the odds of an El Niño developing in autumn or winter to 65 per cent, down from 80 per cent  earlier this month. As NOAA scientist, Michelle L'Heureux,  described recently:

"Waiting for El Niño is starting to feel like Waiting for Godot"

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Surface warming ‘hiatus’ could stick around for another decade, say scientists

  • 21 Aug 2014, 19:00
  • Roz Pidcock

A flip-flopping natural fluctuation in the Atlantic is behind a recent slowdown in surface warming - and it's not due to reverse for another ten years, according to new research.

The theory outlined in a paper  published today in the journal Science disagrees with other research, which pins the blame for the so-called "pause" on changes in the Pacific.

We talked to some other scientists working in the field - and they don't seem convinced.

Puzzle solving

Scientists know greenhouse gases are driving up  global temperature. But data on land and  the surface of the ocean shows  slower than expected warming in the last 15 years or so.

Periods of slower and faster warming  aren't unusual. Scientists say the main reason we're seeing one now is because more heat is finding its way to the  deeper ocean, rather than staying at the surface.

But which ocean? Knowing where the heat is ending up might help scientists predict how long the hiatus will last.

Where Is Global Warming Going _infographic

More than 93 per cent of the heat reaching earth's surface goes into the oceans. Just 2.3 per cent stays in the atmosphere. Source: Skeptical Science

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