“A team of 25 scientists from around the world recently took a stab at answering the question of how sensitive the Earth’s climate is to carbon dioxide and came up with range of possibilities. Their results, published July 22 in Reviews of Geophysics, showed that the planet would most likely warm on average between 4.7 degrees Fahrenheit and 7 degrees Fahrenheit (2.6 degrees Celsius and 3.9 degrees Celsius) if atmospheric carbon dioxide were to double.
This is still a wide span, but it’s much smaller than prior estimated range of 2.7 and 9.1 degrees Fahrenheit (1.5 and 4.5 degrees Celsius) that had been the reigning benchmark for decades.
The new, narrower estimate for climate sensitivity has huge implications, not just for climate science, but for how humanity prepares for a warming world. It shows that the worst-case-scenario is not as dire as previously thought, but also that the best possibilities are still quite grim. In particular, it means that it will be almost impossible to hit the main target of the Paris climate agreement, limiting warming to less than 2 degrees Celsius (3.6 degrees Fahrenheit) this century, by chance; it will require aggressive action to reduce emissions with even less margin for delay.”
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“The resulting estimate of climate sensitivity — 4.7 degrees to 7 degrees Fahrenheit (2.6 degrees Celsius and 3.9 degrees Celsius) — may seem small, but it represents a drastic shift from the world as we know it today. In an editorial in the Hill, Hausfather pointed out that during the last ice age 20,000 years ago, the planet was on average 9 degrees Fahrenheit (5 degrees Celsius) cooler than today. That led to so much ice across the planet that global sea levels were 300 feet lower than they are today.”
“A heat wave begins with high atmospheric pressure building up over an area. A downward-moving air column compresses the air that’s closer to the ground, holding it still and heating it up. That high pressure also forces clouds away and around the column, creating an unobstructed line of light between the ground and the sun.
Over a period of days and weeks, the ground absorbs sunlight, and with stagnant air, heat accumulates and temperatures rise. “There’s nothing coming in and nothing going out,” explained Walt Meier, a senior research scientist at the National Snow and Ice Data Center at the University of Colorado Boulder. “It’s kind of like an oven basically.”
That’s the general formula for heat waves around the world. But there are also several unique ingredients contributing to the Arctic one.
In northern latitudes during the summer, there is near-continuous sunlight — even at night. That allows heat to accumulate faster than in areas that experience sunsets and can cool off in the evening.
Another factor this year was the lack of snow. With an unusually warm winter, less snow built up across parts of the Arctic, and with a warm spring, much of it melted away sooner than usual. “The snow is very reflective of the sunlight,” said Meier. “This year, the snow went away earlier, so then you have the bare ground that can absorb more solar energy.”
The warmer ground also dries out in the heat. With less moisture, there is less evaporation that can cool the surrounding air. “The drier ground and the air over the top of it makes it more susceptible to rapid warming when you have the right conditions like we’re seeing now,” Meier said.”
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“One of the overarching trends behind the heat wave and the wildfires is climate change. Earth as a whole is warming up due to human emissions of greenhouse gases like carbon dioxide. But every place isn’t warming up at the same rate; the Arctic is warming at double the rate of the rest of the planet, which is why some of the earliest effects of climate change are felt in the region. The north pole also presents a window into the future for the rest of the world.
Those higher average temperatures mean extreme heat will become even more likely and more intense, exacerbating threats like forest fires as vegetation dries out. “The wildfires definitely come from the extreme heat and the dryness,” Meier said.
The loss of these ancient, slow-growing forests will release carbon dioxide into the atmosphere that will take decades to reabsorb, further warming the planet. Warming in the Arctic is also thawing permafrost, which releases even more carbon into the atmosphere.
And while it’s summer in the Arctic right now, the region has also experienced heat waves in the winter. In fact, researchers have found that in general, winters are warming faster than summers. That’s part of the reason why the Arctic is now losing sea ice at its fastest rate in 1,500 years.”
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“Antarctica is also warming up. Earlier this year, the continent broke two high-temperature records within a week.”
“The US does not actually have a national grid. Our grid is instead split into three regions — the western interconnection, the eastern interconnection, and, uh, Texas — that largely operate independently and exchange very little power.”
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“this is a barrier preventing all sorts of efficiencies.”
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“87 percent of the nation’s total wind energy potential and 56 percent of its utility-scale solar potential, but are only projected to account for 30 percent of the nation’s energy demand in 2050.”
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“The way to balance this out — to make sure that every region is producing as much renewable energy as possible and that the energy is put to good use — is to connect these regions with high-voltage transmission lines. The more each region can import and export electricity, the more it can balance its own fluctuations in supply and demand with its neighbors’ and maximize the use of renewable energy.”
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“Clack and his co-authors also found that weaving the regionally divided power system into a single national system would save consumers around $47.2 billion a year through increased efficiency and cheaper renewable energy.”
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“The best way to build resiliency against these events, which are increasing in frequency due to climate change, is to connect the regions of the country into a single national grid, so that regions facing difficulty can draw power from neighbors who aren’t.”
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“investment into a national grid would create thousands of construction and maintenance jobs.”
“A small town in Siberia reached a temperature of 100.4 degrees Fahrenheit on Saturday, which, if verified, would mark the hottest temperature ever recorded north of the Arctic Circle.
Temperatures have jumped in recent months to levels rarely seen in the Russian region, and it’s a sign of a broader trend of human-caused climate change that’s transforming weather patterns in the Arctic Circle.
The town of Verkhoyansk is one of the coldest towns on Earth — temperatures dropped to nearly 60 degrees below zero there this past November — and the average June high temperature is 68 degrees.
The 100.4 reading in Verkhoyansk, which sits farther north than Fairbanks, Alaska, would be the northernmost 100-degree reading ever observed.”
“The idea is simple: Someone else can withdraw what you deposit. More specifically, an emitter of a certain quantity of carbon dioxide can pay to compensate for it, leading to no net increase of heat-trapping gases. That compensation can come from planting trees that take in carbon dioxide as they grow, installing renewable energy that replaces fossil fuels, or destroying potent heat-trapping gases like nitrous oxide before they reach the atmosphere.
With an offset, you have an accounting mechanism that bridges greenhouse gas emitters with climate protectors. And offsets are now fueling a multibillion-dollar global market.
But to make a useful carbon offset, you have to consider four key factors.”
“Energy analysts, however, caution that Sanders’s 2030 plan would require a federal infrastructure investment not seen since the construction of the interstate highway system. To get close to Sanders’ 100 percent clean energy goal by 2030, researchers estimate the U.S. would need to add about 800 GW of wind and solar resources — about 25 times the amount the federal government expects to be built this year — along with ample amounts of battery storage and transmission. The Sanders camp forecasts that would cost about $2 trillion.
“Our best year for solar and wind — we’d have to multiply that by three and then sustain it for the next decade,” said Sonia Aggarwal, vice president at the analysis firm Energy Innovation, which advises world governments on their climate targets.
While turning the power grid over to 100 percent renewables presents significant technical difficulties, the clean energy deployment is “not out of the question,” Aggarwal said. However, Sanders’ plan to shut down nuclear power plants will make it “much more difficult.” The nation’s 60 nuclear plants generated more than half of U.S. carbon-free energy last year, but the Sanders campaign says it will phase them out by denying extensions of their operating licenses when they expire.
Many of those nuclear plants have licenses that expire after 2030, but Sanders expects the cheaper solar and wind power to drive most them into retirement. The stability those reactors provide to the power grid would be hard to replace with the variable output of the renewables, said Leah Stokes, assistant professor of political science at the University of California Santa Barbara.”
“Over the years, the terms “free market” and “limited government,” like so many conservative principles, have devolved into little more than rhetorical tics, bits of sloganeering that bear no resemblance to actual conservative governance.
What conservatives seem to have decided is that regulations, restrictions, or limitations — anything that might upset or inconvenience the corporations generating greenhouse gases — are the bad kind of big government and a bad way of picking winners and losers. Government subsidies, tax credits, and grants — anything that might benefit big corporations — is the good kind of big government and a good way of picking winners and losers.”
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“There are plenty of models that show we will need carbon capture (both industrial and natural) to supplement other efforts to reduce emissions. We probably can’t hit our mid-century targets without it.
But there is no model in the world showing emissions falling fast enough with nothing but carbon capture, with fossil fuels continuing their current headlong expansion.
The fossil fuels that remain behind after deep decarbonization, the ones that still need their emissions captured and buried, will be a small vestige of the current fossil fuel regime. That is what every credible model shows. That is the cold, hard truth at the heart of the climate dilemma: There is no avoiding the imperative to reduce fossil fuel combustion and the social and economic disruptions that come with it.
Current Republican efforts to feign climate policy conspicuously fail to grapple with that truth.”