Featured Research

from universities, journals, and other organizations

Rocks can restore our climate ... after 300,000 years

Date:
July 26, 2013
Source:
University of Oxford
Summary:
A study of a global warming event that happened 93 million years ago suggests that Earth can recover from high carbon dioxide emissions faster than thought, but that this process takes around 300,000 years after emissions decline.

A study of a global warming event that happened 93 million years ago suggests that the Earth can recover from high carbon dioxide emissions faster than thought, but that this process takes around 300,000 years after emissions decline.Scientists from Oxford University studied rocks from locations including Beachy Head, near Eastbourne, and South Ferriby, North Lincolnshire, to investigate how chemical weathering of rocks 'rebalanced' the climate after vast amounts of carbon dioxide (CO2) were emitted during more than 10,000 years of volcanic eruptions.

Related Articles


In chemical weathering CO2 from the atmosphere dissolved in rainwater reacts with rocks such as basalt or granite, dissolving them so that this atmospheric carbon then flows into the oceans, where a large proportion is 'trapped' in the bodies of marine organisms.

The team tested the idea that, as CO2 warms the planet, the reactions involved in chemical weathering speed up, causing more CO2 to be 'locked away', until, if CO2 emissions decline, the climate begins to cool again. The Oxford team looked at evidence from the 'Ocean Anoxic Event 2' in the Late Cretaceous when volcanic activity spewed around 10 gigatonnes of CO2 into the atmosphere every year for over 10,000 years. The researchers found that during this period chemical weathering increased, locking away more CO2 as the world warmed and enabling the Earth to stabilise to a cooler climate within 300,000 years, up to four times faster than previously thought.

A report of the research is published in Nature Geoscience.

'Looking at this event is rather like imagining what the Earth would be like if humans disappeared tomorrow,' said Dr Philip Pogge von Strandmann of Oxford University's Department of Earth Sciences, who led the research. 'Volcanic CO2 emissions in this period are similar to, if slightly slower than, current manmade emissions so that we can imagine a scenario in which, after human CO2 emissions ceased, the planet's climate would start to recover and cool down. The bad news is that it's likely this would take around 300,000 years.'

Reconstructing a record of past chemical weathering is challenging because of how plants and animals take carbon out of the environment. To get around this the team used a recently-developed technique involving studying lithium isotopes in marine limestone (this lithium could only come from weathering and is not changed by biological organisms).

The Ocean Anoxic Event 2 is believed to have been caused by a massive increase in volcanic activity in one of three regions: the Caribbean, Madagascar, or the Solomon Islands. The event saw the temperature of seawater around the equator warm by about 3 degrees Celsius. It is thought that this warming caused around 53% of marine species to go extinct. Animals like turtles, fish, and ammonites were amongst those severely affected.

'Everyone remembers the mass extinction of land animals caused by the K-T meteorite impact 30 million years later, thought to be responsible for the demise of the dinosaurs, but in many ways this was just as devastating for marine life,' said Dr Pogge von Strandmann. 'Whilst nutrients from weathering caused a population boom of some species near the surface of the oceans, it also led to a loss of oxygen to the deeper ocean, killing off over half of all marine species and creating a 'dead zone' of decaying animals and plants. It's a scenario we wouldn't want to see repeated today.

'Our research is good news, showing that the Earth can recover up to four times faster than we thought from CO2 emissions, but even if we stopped all emissions today this recovery would still take hundreds of thousands of years. We have to start doing something soon to remove CO2 from the atmosphere if we don't want to see a repeat of the kind of mass extinctions that global warming has triggered in the past.'

The research was supported by the UK's Natural Environment Research Council.


Story Source:

The above story is based on materials provided by University of Oxford. Note: Materials may be edited for content and length.


Journal Reference:

  1. Philip A. E. Pogge von Strandmann, Hugh C. Jenkyns, Richard G. Woodfine. Lithium isotope evidence for enhanced weathering during Oceanic Anoxic Event 2. Nature Geoscience, 2013; DOI: 10.1038/ngeo1875

Cite This Page:

University of Oxford. "Rocks can restore our climate ... after 300,000 years." ScienceDaily. ScienceDaily, 26 July 2013. <www.sciencedaily.com/releases/2013/07/130726074939.htm>.
University of Oxford. (2013, July 26). Rocks can restore our climate ... after 300,000 years. ScienceDaily. Retrieved November 21, 2014 from www.sciencedaily.com/releases/2013/07/130726074939.htm
University of Oxford. "Rocks can restore our climate ... after 300,000 years." ScienceDaily. www.sciencedaily.com/releases/2013/07/130726074939.htm (accessed November 21, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Friday, November 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nations Pledge $9.3 Bn for Green Climate Fund

Nations Pledge $9.3 Bn for Green Climate Fund

AFP (Nov. 20, 2014) Nations meeting in Berlin pledge $9.3 billion (7.4 bn euros) for a climate fund to help poor countries cut emissions and prepare for global warming, just shy of a $10bn target. Duration: 00:46 Video provided by AFP
Powered by NewsLook.com
What's The Point Of Climate Conferences?

What's The Point Of Climate Conferences?

Newsy (Nov. 20, 2014) There's optimism about the U.N.'s climate conference in Paris next year, and if climate conferences past are anything to go off, that's notable. Video provided by Newsy
Powered by NewsLook.com
Mysterious Glow Worms Found in the Amazon

Mysterious Glow Worms Found in the Amazon

Buzz60 (Nov. 20, 2014) Wildlife photographer Jeff Cremer teamed up with entomologist Aaron Pomerantz and others to investigate a predatory glow worm found in the Amazon. Patrick Jones (@Patrick_E_Jones) explains. Video provided by Buzz60
Powered by NewsLook.com
N.Y. Snowfall Renews Climate Change Discussion

N.Y. Snowfall Renews Climate Change Discussion

Newsy (Nov. 20, 2014) Record snowfalls in New York are helping to reinforce new climate catchphrases. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins