On the remote Norwegian island of Spitsbergen, well inside the Arctic Circle, a deep gash in a dirty-gray glacier gushes like a severed artery (above). Tinted red by a mysterious infusion of dissolved iron, this and other glacial deluges could have a serious impact on coastlines, and even climate, worldwide.
Glaciers all around the globe are melting, and recent studies reveal that small glaciers on Spitsbergen and other Arctic islands are melting fastest of all. By how much that melting ice will raise sea level is an important question, especially as the public comes to terms with new estimates that sea level rise from melting ice will affect tens of millions more people than originally predicted:
NEWS: Climate Change Impact: Underestimated?
NEWS: Oceans Could Rise 5 Feet by 2100
Recently, though, researchers have also begun wondering if the demise of ice might actually help combat global warming. That’s where the iron comes in: A big influx of this essential nutrient could remove heat-trapping carbon dioxide from the air by stimulating a bloom of microscopic plants, which lap up CO2 for photosynthesis. That’s precisely the idea behind so-called “iron fertilization” schemes, which require dumping massive loads of iron filings into the sea—and have proven controversial:
NEWS: Ocean Geoengineering Scheme May Prove Lethal
So, could melting glaciers fertilize the seas instead? The answer depends on how much iron the melt water contains and how much of it actually gets to parts of the ocean where the nutrient is scarce. It is also important to determine the chemical form of the iron, as not all are created equal. Microscopic plants can readily use some forms of iron and not others.
Recent studies have shown that the iron long known to enter the oceans via rivers and wind-blown dust is not always so bioavailable but that iron in icebergs and glaciers may well be.
“No one has looked at the input of this iron to oceans before,” geochemist Laura Wehrmann told Discovery News. Keen to be the first to do so, she and two colleagues at the University of California, Riverside, braved Spitsbergen’s polar bears and near-freezing temperatures to collect samples this past September. Now, they are busy analyzing them back in the lab.
Here are some other details of their adventure:
Getting to the bleeding glacier that drew researchers to the Far North required a half-day hike across bear territory. To protect against potentially irate bears, one person is required to carry a gun any time researchers mosey away from base camp.
On this trip, the job fell to Wehrmann (above), who was meeting her new postdoctoral fellowship adviser, Tim Lyons, and graduate student Jeremy Owens for the first time face to face. “I was thinking, ‘I hope no polar bear attacks my new boss before I’ve even started working for him!’” Wehrmann recalled.
Downstream from the gushing gash, in the glacier’s outwash plain, the trio found that deluge lost none of its bright color as it split into a braided stream on its way to the sea (below, left). Where the tinted waters entered the sea, they form a wide, pink plume visible from shore (below, right).
The bleeding glaciers may be the most intriguing to look at, but it is just as possible that bioavailable iron may be flowing in clear-flowing glacial melt water as well. To get a good set of samples for comparison, the trio traveled by zodiac across the fjord to the foot of a glacier known to run clear. Because the seawater hovers just one degree above freezing, that jaunt required the researchers don bright orange survival suits (below).
IMAGES:
Dissolved iron accounts for red waters gushing out of a melting glacier on Norwegian island of Spitsbergen.
Laura Wehrmann, toting a firearm to protect against polar bears.
Glacial melt water retains its red tint all the way to the sea, where it spreads out as a pink plume along the horizon.
Not all of Spitsbergen's glaciers run red; clear waters may contain important traces of iron as well.
All photographs courtesy Tim Lyons, UC Riverside
Tags: Adventure, Climate Change, Geophysics, Glaciers, Global Warming
comments ( )