Wyrd - OE: that which has become; fate-shaping; destiny-unfolding

Thursday, 22 May 2014

Grasping for silver linings ...and blooming saviours

Plankton blooms swirl north of Norway (ESA)
In the ongoing blizzard of climate change worries, it's always nice to spot a break in an otherwise relentlessly overcast sky. In fact, it only takes the briefest glimpse of 'good-news' research, and some are already polishing up the silver-lining they've just spotted in the swirling clouds. Today was just such a day for the polishers. 

"Iron from melting ice sheets may help buffer global warming"

That's the lead from a press-release accompanying an interesting new paper in Nature. The paper's authors have found that melting ice sheets in Greenland and Antartica aren't just cranking up sea-levels, inch-by-worrying-inch. They're also pumping out iron - an important nutrient - into the seas surrounding them. Given that a little bit of extra iron has been shown to boost the growth of blooms of phytoplankton - the tiny micro-organisms that are the basis of nearly all marine life - and that phytoplankton absorbs CO2 - the headache gas of global warming - it's easy enough to spot the kernel of a good-news story.

Nanoparticulate ferrihyrite in all its glory
It's not just any old iron, either, that ice-sheets are spilling into the sea, after grinding away at the mountains in the hinterland. The iron they are gifting to the oceans consists of hosts of tiny nano-sized iron particles, something that scientists call 'bioavailable iron'. That means the iron is readily absorbed by critters like phytoplankton. And without a paucity of iron holding them back, those plankton blooms can really boom.

The fact that melting glaciers are a major source of this 'bioavailable' iron is something of a novel concept. It may go some way towards explaining the large blooms of phytoplankton that colour the Arctic ocean in spring and summer. So this paper is major step forward in understanding the complex interweave between climate, chemistry and life in the coldest spots on the planet. But does this new research also point the way towards phytoplankton blooms as a force for good in the battle against climate change?

Friday, 9 May 2014

Is the 'little fella' about to bring big trouble in his wake?

Peruvian fishermen fear him, hurricane-battered Pacific islanders hope for him, and parched Californians are right now praying for him. El Niño - the 'little boy' or Christ-child - is gathering himself for a reappearance later this year, ready to wreak havoc with weather across the globe. Today the US's Climate Prediction Center pegged the chances of an El Niño event swarming across the Pacific at 65% for the summer - and 80% for the autumn.

With the hot-tempered little lad come changes across the globe - from heightened fire-risk in Australia and winter cloudbursts in California, to fisheries failures in the east Pacific. Naturally enough, headline writers are rolling out the gloom-and-doom headlines. Time to mark up a notch to the growing chorus of 'climate chaos', then? 

Not so fast.

After all, El Niño, for all its global meteorological drama, is part of a natural rhythm of wind and ocean movements, which have persisted for millennia. 

The sea-temperatures across the middle of the world's largest ocean have beat out an erratic pulse between hot (El Niño) and cool (La Niña) since at least the start of the last ice-age. There is certainly drama in El Niño, and the wave of consequences it pushes across the rest of the world. But it is a drama that's rather long in the tooth.

Thursday, 29 August 2013

Of monsters, methane and the burdensome sea

It's the ultimate tipping point - the so-called Methane Burp. Gigatons (Gt) of methane are released into the atmosphere by some sudden phase change in the earth's climate system.
Plumes of methane in Arctic Ocean (Westbrook et al, 2009)

With its vastly greater global warming potential - up to 100 times more powerful than CO2, over short timescales - a sudden pulse of methane would accelerate human-caused global warming. It could even cause a cascade of other knock-on effects (Amazon deforestation, collapse of the ice-sheets) so creating a runaway greenhouse effect.

It's that sort of a scenario - with 50Gt of methane gushing from a source in the Arctic over 10-20 years - that was recently modeled by economists in Nature. They put a $60 trillion price tag for the global economy from the consequences of ratcheting upwards man-made climate change. A scary monster, made even more real by describing it in the language our leaders understand most - hard cash.

But the Methane Burp is also complete fantasy - at least according to some recent detractors. Many climate scientists believe the methane locked up in frozen soils, or the curious, icy 'methane-hydrates' under the sea-floor, are a real threat - but only as a slow-burn cooker for the globe's climate. As the planet warms, the natural emissions from these sources will increase, they believe. But not at a rate that will be catastrophic. They struggle to see how anything like as large as 50,000 million tonnes of methane can erupt so quickly from Arctic permafrost, or sub-sea methane hydrates. Such sources have been thought to have been stable in the recent geological past.

Sunday, 2 June 2013

From White to Green - Greenland's Glaciers are History

Article first published as From White to Green - Greenland's Glaciers are History on Technorati.

Greenland ice sheets (Credit: destination arctic circle/ Flickr)
Take a long hard look at Greenland's towering glacial caps - they may well already be history. That's according to a paper published in Nature Climate Change. Scientists have already noticed that the speed at which Greenland's glaciers are rushing into the sea has accelerated. And they have long-feared that, without commitments to curb our greenhouse gas emissions, much of its ice cap will eventually disappear into the sea.

But there is now research to suggest the threshold has already been passed. Previous models made some fairly simple assumptions about how the 2 mile-thick ice block, which is plastered over much of Greenland, will melt. And they gave some hope that the worst of the melting could still be avoided, if we were to pull the plug on our emissions.

Fade to green?

With this new research, however, the physics of Greenland's ice-melting process have been painted out in finer detail. And if the authors are right, the amount of global warming we have stored up, from our emissions so far, may be enough to transform Greenland. The world's biggest island could shift from an icy whiteness to a truly green land.

Ice sheet thickness (km) today (E1) and projected in future (E2/3)
The reason for the change in outlook? The simple realization that as the 2-mile high icy plateaus melt they get considerably lower. And the lower the ice surface, the warmer the air above them gets, pushing the pace of melt even faster – a positive feedback.

Positive feedbacks are the 'loaded dice' of the game of climate crap-shoot we're playing. They push the odds in favor of dangerous consequences, by accelerating the rates of change kicked off by global warming. But how dangerous would it be, if Greenland were to disgorge its entire ice sheet into the oceans, as this study suggests?

Sunday, 3 February 2013

A Book of Kells for the climate - scribe-illustrators needed?

The world of climate science sometimes seems like a swirling sea of numbers. Numbers that come, and numbers that go, like waves breaking silently on the foreshore. There's always another statistic, or table, or figure about to break, ready to erase the brief imprint of the last. But occasionally that sea tosses up a stunningly crafted piece of driftwood - and here's one I found beach-combing the wilder shores of green think-tankery:

This is one of many visual gems to be found in the World Resources Institute's report, 'Navigating the Numbers'. It tried to summarize the state of play for greenhouse gases and climate policy a few years back. I love this picture, because it takes all of those all-often-hurled statistics and beds them into a beautifully-colored context. All of the data is there, of course, showing on how each and every part of our society is contributing to our shocking of the climate.

Monday, 12 November 2012

Ten tall-tales from the skeptics – the come-backs to topple them

Photo Credit: WireWizard
First published on EarthTimes as "Ten tall-tales from the climate change skeptics

The devil has all of the best songs, so they say. And the climate-change denial camp have certainly banged out their tunes to good effect, over the last few years. It's not hard to see why the clamor of the climate skeptics has won more and more of those thronging in the stalls. But if you're caught out by one of those seductive refrains from the naysayers, what you need is counter-melody to cut them short. So what are the top-ten comebacks to the tall-tales often peddled by the denialist community?

1 Warming isn't really happening, it's all down to the 'urban heat-island effect'
The consensus that the planet is warming didn't just drop off of a graph of dodgily-placed thermometers. Yes, cities and towns are warmer than the countryside, and yes, urban areas have swallowed rural ones over the last century. But climate scientists try to correct for these when working out the globe's average temperature.

And the indicators that temperatures are rising come from a myriad of sources, not just land-based temperature records. Satellites, tree-rings, snow and ice-cores, stalactites and corals – all of these are used to piece together the global temperature record. And they confirm that the recent warming is unprecedented.

Monday, 5 November 2012

Black stain or clean climate?

First published on Earth Times as "Clean stoves could save lives and maybe the climate too"

Flecks of soot from a smoky open fire in India blacken more than just the roofs of the hut it is smoldering in. Fine particles of such smoke lodge deep in the lungs of women preparing meals, gifting them a dark scourge of ill-health and premature death. That same black soot floats higher into the air, where it helps to change the way clouds form - and so to warm the climate. Some specks may even end up coating ice in the frozen extremes of the planet, dulling their pristine surfaces, and hastening the melt of glaciers and ice-caps.

And recent reports suggest that the weakening monsoon in India, and unprecedented storms in the Arabian Sea, may owe their genesis to the smoggy brown clouds gathered over the Indian sub-continent. For such tiny little particles, soot appears to be having mammoth impacts, and in a host of different ways. But the problem of soot is not one of those tangled and knotted issues that needs an impossibly herculean effort to sort out. It may be that its dark legacy can be addressed by something as simple as a clean-burning stove.

From cooking to climate change

The problem of the gathering smoggy clouds over many parts of the developing world has been visible for decades. But only recently have all of the implications become apparent. Some of the particles making up the haze come from wildfires; some from coal-burning power stations; some from diesel-fumes, as urban traffic swells. But in many places, and especially in the Indian sub-continent, a large share comes from cooking stoves. It is thought that up to 3 billion people worldwide still cook over open fires or stoves, filling their homes, and the local atmosphere, with smoke. Maybe 800 million of these people are in India, in both cities and villages. And the sheer number of their cooking fires is helping to build up a 2 mile-thick hazy cloud over much of South Asia.