Revealed: The Earth's 'electrical heartbeat' seen in clouds

Mar 07, 2013

(Phys.org) —The height of clouds changes by up to 200m during a day under the influence of a global 'electrical heartbeat' in the atmosphere, scientists at the University of Reading have discovered.

The findings, made by analysing 10 years' data of cloud heights from the north and south poles, open up a whole new perspective on our understanding of how clouds form and influence our weather and climate.

Scientists have been aware of the daily global ebb and flow of electric current through the atmosphere for 100 years, when it was shown to vary consistently throughout the day wherever on the planet it was measured. This regular variation, effectively a global electrical heartbeat, is known as the Carnegie curve, after the ship whose cruises provided the defining experiments in the 1920s.

The electric current is caused by electrified storms across the world. Its daily peak occurs at 7pm GMT each day when the major sources of thunderstorms are the American and African landmasses. The current is usually weakest at 3am GMT, night-time across most of the world's , when there are fewest thunderstorms occurring globally.

This video is not supported by your browser at this time.

Previously no connection had been made between this current and the formation of clouds. But, by analysing  cloud base measurements made during polar darkness when there are few other influences on , University of Reading meteorologists Professor Giles Harrison and Dr Maarten Ambaum found evidence for the first time that cloud heights are closely linked to the Carnegie curve.

Professor Harrison said: "What we found was remarkable. The variations from both north and south poles are almost identical, suggesting a strong link with the Carnegie curve, when other factors are taken out of the equation. This may arise from charging of small in the cloud's base, encouraging them to stick together.

"This implies that factors inside or outside the climate system which change the global , such as ocean temperatures or cosmic rays, may influence the properties of layer clouds. However our results say nothing about any long-term effects, as they were found for rapidly-occurring changes from hour to hour."

Layer clouds are particularly relevant to global temperatures. At night they act like a warm blanket, preventing heat from being lost from the earth into space, and during the day help cool the surface by reflecting away the sun's energy.

"The realisation the electrical of the planet plays a role in the formation of layer clouds indicates that existing models for and climate are still missing potentially important components," said Dr Ambaum.

"Understanding these missing elements is crucial to improve the accuracy of our weather forecasts and predicting changes to our climate. The keeps on surprising us with its immense complexity and richness."

The findings are published in the journal Environmental Research Letters.

Explore further: NASA gets two last looks at Tropical Cyclone Jack

More information: Harrison, G. and Ambaum, M. 2013 Electrical signature in polar night cloud base variations, Environ. Res. Lett. 8 015027 iopscience.iop.org/1748-9326/8/1/015027/article

Related Stories

The birth of a cloud droplet

Oct 31, 2011

(PhysOrg.com) -- Wrapped in mystery, the formation of a cloud droplet comes down to physics. Pacific Northwest National Laboratory led a research team that has helped peel away another layer of the cloud droplet ...

The proof is in the clouds

Jan 26, 2012

For most people, clouds are just an indication of whether it's a "good" or "bad" day. A team of scientists from Pacific Northwest National Laboratory found that certain clouds hold the key to climate behavior ...

Recommended for you

NASA sees last vestiges of Tropical Depression Jack

10 hours ago

Tropical Cyclone Jack had weakened to a tropical depression when NASA and JAXA's Tropical Rainfall Measuring Mission (TRMM) satellite passed above on April 22, 2014 at 1120 UTC/7:20 a.m. EDT.

New discovery helps solve mystery source of African lava

13 hours ago

Floods of molten lava may sound like the stuff of apocalyptic theorists, but history is littered with evidence of such past events where vast lava outpourings originating deep in the Earth accompany the breakup ...

Climate change likely to make Everest even riskier

14 hours ago

Climbing to the roof of the world is becoming less predictable and possibly more dangerous, scientists say, as climate change brings warmer temperatures that may eat through the ice and snow on Mount Everest.

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

cantdrive85
1.6 / 5 (7) Mar 07, 2013
The electric current is caused by electrified storms across the world.


Cart in front of the horse, the current creates the storms. The daily ebb and flow is due to the Earth interacting with the Sun's currents.

"From the smallest particle to the largest galactic formation, a web of electrical circuitry connects and unifies all of nature, organizing galaxies, energizing stars, giving birth to planets and, on our own world, controlling weather and animating biological organisms. There are no isolated islands in an electric universe."

~David Talbott and Wallace Thornhill, Thunderbolts of the Gods
Maggnus
5 / 5 (2) Mar 07, 2013
Of course, the title of the article had electrical in it. And there's cantthinkcoherently.

Why am I NOT surprised? In fact, I am so NOT surprised that I could fall down and have a heart attack from NOT suprised!
barakn
5 / 5 (1) Mar 07, 2013
Cart in front of the horse, the current creates the storms. The daily ebb and flow is due to the Earth interacting with the Sun's currents.

How does your external model explain the timing of the diurnal rhythm?

More news stories

On global warming, settled science and George Brandis

The Australian Attorney General, Senator George Brandis is no stranger to controversy. His statement in parliament that "people do have a right to be bigots" rapidly gained him notoriety, and it isn't hard to understand why ...