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Study Links Human Actions To Specific Arctic Ice Melt (sciencemag.org)
sciencehabit writes from a report via Science Magazine: Since at least the 1960s, the shrinkage of the ice cap over the Arctic Ocean has advanced in lockstep with the amount of greenhouse gases humans have sent into the atmosphere, according to a study published this week in Science. Every additional metric ton of carbon dioxide (CO2) puffed into the atmosphere appears to cost the Arctic another 3 square meters of summer sea ice -- a simple and direct observational link that has been sitting under scientists' noses. If current emission trends hold, the study suggests the Arctic will be ice free by 2045 -- far sooner than some climate models predict. The study suggests that those models are underestimating how warm the Arctic has already become and how fast that melting will proceed. And it gives the public and policymakers a concrete illustration of the consequences of burning fossil fuels. For instance, a U.S. family of four would claim nearly 200 square meters of sea ice, based on U.S. emissions in 2013. Over 3 decades, that family would be responsible for destroying more than an American football field's worth of ice.
A) Gore isn't a scientist, and B) his statement was that "some models" predict it in summer months. For what it's worth the summer arctic sea ice extent did fall to half of the 1981 to 2010 average in 2012. (Middle of the road models may have been spot on...)
The problem with the Titanic is that it failed because of an engineering failure. Something didn't work as planned. Reactors such as pebble bed reactors and molten salt reactors do what they do because of the laws of physics (vs the laws of engineering where everything gets screwed up if a valve breaks.). For example, with both pebble bed and molten salt reactors, they have run tests where they have turned off all coolant. Yea, they get hot but they self modulate because of how they are designed. For them to not work would require the laws of physics to stop working as well. To dive further into the example, pebble bed reactors are basically a giant tub of balls. Each ball has a specific amount of nuclear material in the center and are surrounded by an outside shell. As the reactor runs, they get hot as you'd expect. However, as the balls heat up, they also expand and when they expand, they push the neighboring balls away which slows the reaction. For pebble bed reactors to overheat, the laws of physics that cause hot items to expand would have to cease working. Molten salt reactors work a bit differently though not that much differently.
I like solar. It is great. I'm considering installing it on my house. It just doesn't have the energy density needed to drive modern societies. How many solar panels will it take to power a steel mill? The solar projects in the Nevada desert have been a failure by and large and are more a kickback for Harry Reid than anything else. Wind it cool too. Not many places where you can install it. My brother works for the company that fixes windmills. He says they are far from environmental and are frequently abandoned as soon as the federal funding runs out. The fiberglass blades need to be constantly repaired and then replaced while the old ones go to the landfill as there isn't any way to recycle fiberglass. They leak oil like a sieve and the gearing breaks down due to the immense torque needed to ramp up the RPMs. (They gear up the RPMs from approximately 6 RPM to 1,000 RPM to get the generators to work.) I'm all for alternative sources of power. In fact, I think that most new houses should have passive solar as a matter of course. I've always been puzzled why people don't do this as it is basically free power / lower energy bills. Even so, nuclear is the only power source that can power a modern society.
Misquoting Al Gore is "funny" not "informative".
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Um. Any one else see a problem with using surface area to describe a volumetric substance?
Yes, it's misleading. Since the 1960's, 40-50% of the ice has melted when measured by surface area, but 70-80% of has melted when measured by volume. The volume measurements come from the US navy who declassified historical ice thickness data from it's nuclear submarine fleet about a decade ago. More recent data comes from satellite measurements.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
...there is no intrinsic necessity that the arctic be iced over.
You are absolutely correct. Just like there is no intrinsic necessity that New Orleans, New York, and Miami are above water.