Feeds

Humanity fingered in pre-industrial pollution racket

Slash and burn

Secure remote control for conventional and virtual desktops

Humanity has been affecting the climate for longer than previously imagined, according to scientists studying the history of the planet's atmosphere.

Researchers at New Zealand's National Institute of Water & Atmospheric Research (NIWA) examined tiny air bubbles trapped in ice cores drilled in East Antarctica.

They found that levels of atmospheric methane around 2,000 years ago were much higher than expected. The levels start to drop off after around 1,000AD, however, remaining low until the beginning of the industrial age, when they began to rise rapidly again, the researchers found.

Forest and grassland fires are a significant source of atmospheric methane. The presence of these larger quantities of methane so long ago suggests that there must have been more fires than would have occurred without human intervention.

The results tally well with both climate change, and human land use, according to the paper’s lead author, Dr Dominic Ferretti.

The analysis suggests that between 0 and 1500 AD, the indigenous population of the Americas regularly burned grassland and woodland areas, perhaps for agriculture and hunting. The arrival of Europeans caused a population crash, and with the declining numbers, the burning and methane production was also reduced.

In addition, the researchers say dry periods, like those triggered by El Niño events, correspond to higher levels of methane. They conclude that as global temperatures rise, forest fires will become more common, releasing more methane into the atmosphere.

Methane is a potent greenhouse gas, with an insulating effect 20 times as strong as that of carbon dioxide. The main difference is that it is not very stable, and only persists in the atmosphere for around 20 years. CO2, on the other hand, will happily stick around for a couple of centuries. ®

Boost IT visibility and business value

More from The Register

next story
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
Cutting cancer rates: Data, models and a happy ending?
How surgery might be making cancer prognoses worse
Boffins ID freakish spine-smothered prehistoric critter: The CLAW gave it away
Bizarre-looking creature actually related to velvet worms
CRR-CRRRK, beep, beep: Mars space truck backs out of slippery sand trap
Curiosity finds new drilling target after course correction
Brit balloon bod Bodnar overflies North Pole
B-64 amateur ultralight payload approaching second circumnavigation
Galileo, Galileo! Galileo, Galileo! Galileo fit to go. Magnifico
I'm just a poor boy, nobody loves me. But at least I can find my way with ESA GPS by 2017
Astronomers scramble for obs on new comet
Amateur gets fifth confirmed discovery
Boffins build CYBORG-MOTHRA but not for evil: For search & rescue
This tiny bio-bot will chew through your clothes then save your life
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?