Sheri Edwards's List: Global Warming

• Greenland
• an abrupt, islandwide melt was imminent
• how fast the world's seas are likely to rise as a result of global warming

  • Greenland is melting fast -- faster than scientists thought. That means that the world's seas may rise faster also.
• The ice sheet, scientists believed, was a mostly inert ice cube frozen fast at its bed; if the glaciers melted because of global warming, the process would be, well, glacial.

  • Scientists thought because the glaciers were so huge, they would melt in a slow way. They were wrong.
• melting on the ice's surface can cause large sections of the ice sheet to break free of its moorings in hours, not millennia.

  • Evidence now shows scientists that if the glacier starts to melt on the top, it will melt fast all the way through.
• suddenly pouring into the ocean at twice the rate previously measured,
• his measurement of Greenland's reflectivity, or "albedo."
• snow is white: When sunlight hits a glacier, most of it bounces back into space, instead of being absorbed by dark-blue oceans or green forests.
• As snow crystals warm – even before they melt – they lose their jagged edges and become rounder, reflecting less light.
• wet sand is darker than dry sand
• Fresh snow bounces back 84 percent of the light that hits it; warm, rounded crystals can reflect as little as 70 percent
• a steady darkening in Greenland's albedo, from a July average of 74 percent when the century began to about 68 percent last year.

  • Snow reflects light and that helps keep the earth cool. Now that the glacier's are melting, the once jagged crystals are now rounded, reflecting less light.
• soot from the wildfires raging in Colorado and Siberia
• "Greenland is a sleeping giant that's waking," says Box. "In this new climate, the ice sheet is going to keep shrinking – the only question is how fast."

  • The glaciers are thus melting faster than ever thought possible.
• Simply by changing the albedo of the Greenland ice sheet, Box calculates, the island now absorbs more extra energy each summer than the U.S. consumes in a year.
• trapping more of the sun's rays than all the cars and factories and furnaces produce in the world's biggest economy.
• he planet's destiny may have been revealed, in a single season, by the quiet metamorphosis of a silent, empty sheet of ice.

  • SummaryThe albedo, the frozen, reflective areas, has decreased so much that Greenland now absorbs more sunlight energy in a summer than the US absorb or produces in a year!

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  • • The albedo, the frozen, reflective areas, has decreased so much that Greenland now absorbs more sunlight energy in a summer than the US absorb or produces in a year!

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• disappearance of an icy landscape that took thousands of years to form
• Everywhere, glaciers and ice sheets have begun breaking apart and accelerating toward the oceans faster than ever imagined possible.
• we get to some point that the changes become pretty much unstoppable.
• ice has frequently advanced and receded, but now it's changing in ways we don't fully understand.
• cryosphere, the frozen regions of the earth.
• On the Greenland ice sheet, a crack opens and a mile-wide lake pours down a 3,000-foot chasm.

• drilling down into the ice sheet.

    
• water is just
• Changes in the ice are normal. It is volatile and constantly in flux, but what Balog is witnessing suggests something extraordinary is going on.

  • It is more than just normal changes. Something else is making the glaciers melt faster than normal.
• how fast will the world's glaciers and ice sheets melt, and what will all that melting mean for us?
• His Extreme Ice Survey is the largest photographic study of the cryosphere ever attempted. He is deploying 26 time-lapse cameras on glaciers across the northern hemisphere and programming them to shoot a frame every daylight hour for three years
• The fact that the ice is changing is nothing new. Over the millennia, the expansion and contraction of ice across the continents has fundamentally altered the planet, gouging out lakes and valleys and pushing man around the earth.
• In the past, the cycle of ice ages and periods of warming were caused mainly by shifts in the earth's orbit around the sun, but now, humans seem to be driving these changes. Since the Industrial Revolution, our burning of fossil fuels has ratcheted up the output of greenhouse gases like carbon dioxide, which trap heat in the atmosphere. Temperatures are climbing, and the ice is melting faster than ever.

• Over the last 40 years, temperatures here in Alaska have risen about four degrees Fahrenheit, twice as fast as the global average. Now these rivers of ice are flowing faster and crashing even more spectacularly into the sea.

      

  Some people are taking advantage of the glacial fireworks while they last. Surfers towed in by jet skis are playing a dangerous game of chicken with the ice.

• Alaska's Columbia is one of the biggest ocean-feeding glaciers in North America.

      

  In the early 1980s, the Columbia started flowing faster and began calving far more ice into the ocean than was being replenished by snowfall upstream. Balog and the Extreme Ice Survey glaciologists are trying to figure out how much ice the Columbia is losing and whether or not it can survive.
• As the glacier moves, it churns up dirt and rocks that collect on its surface. The Columbia is so vast, it's hard to imagine it vanishing.
• lthough calving is normal, the Columbia is hemorrhaging ice so quickly that in the last 30 years the glacier has receded 10 miles up the fjord.
• Balog's time-lapse images capture a rate of retreat that shows no sign of stopping. In the last year alone, the Columbia lost another half-mile of ice.

  • So the glacier is melting much faster than expected. Why?
• I really never expected that we were going to see changes of anything like this kind of magnitude in the period of time we had to work on this.

• They're installing seismometers that pick up the vibrations of icequakes, tremors that reverberate through the ice as it calves. From the seismic data, a pattern emerges that points to one clear culprit, water.

      

  They knew water was melting the ice, but it appears that it's prying the ice apart, like a powerful lever.

• the water pours into the cracks in the glacier and wedges it apart.

      

  The result is increased calving and a quicker demise of the glacier.

  • So the glacier starts melting. Then the water pours into cracks and pushes the glacier apart. Then it is melting faster in the smaller pieces. The flow of melting water makes the glacier melt faster.

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• Lakes, ponds, rivers, and streams are freshwater habitats. So too are swamps, bogs, and marshes. Lumped together, these ecosystems contain all the water in the world that is not frozen, essentially salt-free, and accessible to humans.

    

  It amounts to precious little water, less than half a percent of the world's water supply. Yet it is vital to the survival of humans and a wide range of critters from dragonflies and piranhas to beavers and bullfrogs.

    

  Lakes and ponds are basins of water surrounded by land, whereas rivers and streams are the arteries that move fresh water from land, such as mountain peaks, to the oceans. At the edge of many lakes and rivers are saturated wetlands—the swamps, bogs, and marshes—that support myriad types of plant and animal life, prevent floods, retain sediments, and purify drinking water. All the freshwater ecosystems can be found within a watershed—a set of habitats that drain into a single body of water such as a big lake or the ocean.

• • The Columbia River basin comprises some 260,000 square miles, from its   headwaters in British Columbia, Canada, to its mouth at Astoria, Ore.,   bordering Washington and Oregon. 

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• The Columbia River basin comprises some 260,000 square miles, from its   headwaters in British Columbia, Canada, to its mouth at Astoria, Ore.,   bordering Washington and Oregon.
• The basin includes parts of seven states, 13 federally recognized   Indian reservations, and one Canadian province. Nineteen percent of the   watershed is in Washington.

• • The basin includes parts of seven states, 13 federally recognized   Indian reservations, and one Canadian province. Nineteen percent of the   watershed is in Washington. 

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• The river’s annual discharge rate fluctuates with precipitation and   ranges from 120,000 cfs in a low water year to 260,000 cfs in a high   water year.
• The river’s annual discharge rate fluctuates with precipitation and   ranges from 120,000 cfs in a low water year to 260,000 cfs in a high   water year.

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• Climate Change: The Climate Impacts Group at the University of Washington has conducted the definitive work to date in applying global climate models to predict future hydrologic responses in the Columbia River Basin. As air temperatures rise in this region, snowpack diminishes. Snowpack is a natural “reservoir” of water that feeds the Columbia River and its tributaries during the summer months. Reduced snowpack translates to reduced stream flow. There is substantial debate about whether precipitation will change in the future. Decreased snowpack will also cause decrease in the quantity of water recharging groundwater systems, resulting in a decrease in groundwater discharge to streams. Rising air temperature and decreased groundwater recharge lead to projections that warming stream temperatures will stress coldwater fishes (e.g., endangered salmon).

   

   Glacial Melt: Moreover, widespread glacial retreat is occurring throughout the region. British Columbian scientists are now predicting a loss of up to 90% of B.C. glaciers over the next 150 years. Glaciers in the Columbia Icefields form the headwaters of the Columbia River. Glacial melt may have a near-term effect of increasing summer flows, but will reduce summer flows in the longterm. Loss of glaciers will profoundly affect when and how the river flows.

   

• North America: "Heavily-utilized water systems of the western US and Canada, such as the Columbia River, that rely on capturing snowmelt runoff will be especially vulnerable," says the Fourth report of IPCC Working Group II.

   

  A two degree C warming by the 2040s is likely to lead to sharply reduced summer flows coinciding with sharply rising demand.

   

  The report estimates that Portland, Oregon will by then require over 26 million additional cubic meters of water as a result of climate change and population growth. This will coincide with a fall in summer supplies from the Columbia River by an estimated five million cubic meters.

   

  Meanwhile, just over 40 per cent of the supply to southern California is likely to be vulnerable by the 2020s due to warming triggering losses of the Sierra Nevada and Colorado River basin snow pack.