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3 New Papers: Greenland 3-5°C Warmer With 40 Kilometers Less Ice Area 4,000-10,000 Years Ago

3 New Papers: Greenland 3-5°C Warmer With 40 Kilometers Less Ice Area 4,000-10,000 Years Ago

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Greenland Cooling Since 2005

Arctic Region Cooler Now Than Most Of The Last 10,000 Years


It’s official.  According to a new paper published in the journal Scientific Reports, Greenland has been cooling slightly since 2005.

This trend development may be a harbinger of what may be in store for the coming years.  Shifts in North Atlantic temperatures typically lead changes in the Arctic  by a few years.  And throughout the North Atlantic, rapid cooling has been underway since 2005, plunging below the levels reached in the 1950s.


Kobashi et al., 2017

For the most recent 10 years (2005 to 2015), apart from the anomalously warm year of 2010, mean annual temperatures at the Summit exhibit a slightly decreasing trend in accordance with northern North Atlantic-wide cooling.  The Summit temperatures are well correlated with southwest coastal records (Ilulissat, Kangerlussuaq, Nuuk, and Qaqortoq).”


A Few Thousand Years Ago, The Greenland/Arctic Region Was 3-5°C Warmer Than Now


Between 10,000 and 4,000 years ago, atmospheric CO2 concentrations were almost 150 ppm lower than they are now (~260 ppm).  Despite such low CO2 levels, the Arctic region was several degrees Celsius warmer than it has been in recent decades.   Arctic summers were likely sea ice-free during these much warmer years.


Mangerud and Svendsen, 2017

“Shallow marine molluscs that are today extinct close to Svalbard, because of the cold climate, are found in deposits there dating to the early Holocene. The most warmth-demanding species found, Zirfaea crispata, currently has a northern limit 1000 km farther south, indicating that August temperatures on Svalbard were 6°C warmer at around 10.2–9.2 cal. ka BP [10,200 to 9,200 years ago], when this species lived there. … After 8.2 cal. ka, the climate around Svalbard warmed again, and although it did not reach the same peak in temperatures as prior to 9 ka, it was nevertheless some 4°C warmer than present between 8.2 and 6 cal. ka BP. Thereafter, a gradual cooling brought temperatures to the present level at about 4.5 cal. ka BP. The warm early-Holocene climate around Svalbard was driven primarily by higher insolation and greater influx of warm Atlantic Water, but feedback processes further influenced the regional climate.”


Lasher et al., 2017

“This paper presents a multi proxy lake record of NW Greenland Holocene climate. … Summer temperatures (2.5–4 °C warmer than present) persisted until 4 ka [4,000 years ago] … Continual cooling after 4 ka led to coldest temperatures after 1.2 ka, with temperature anomalies 2-3°C below present.  Approximately 1000 km to the south, a 2-3°C July temperature anomaly (relative to [warmer than] present) between 6 and 5 ka [thousand years ago] was reported based upon chironomid assemblages near Illulisat and Jakobshavn (Axford et al., 2013). Across Baffin Bay on northeastern Baffin Island, HTM [Holocene Thermal Maximum] summer temperatures were an estimated ~5°C warmer than the pre-industrial late Holocene and 3.5°C warmer than present, based upon chironomid assemblages (Axford et al., 2009; Thomas et al., 2007).”


Kobashi et al., 2017

“After the 8.2 ka event, Greenland temperature reached the Holocene thermal maximum with the warmest decades occurring during the Holocene (2.9 ± 1.4°C warmer than the recent decades [1988-2015]) at 7960 ± 30 years B.P.”


No Net Warming For The Greenland Ice Sheet In 90 Years


Kobashi et al., 2017


Zhao et al., 2016


Hanna et al., 2011


Greenland Ice Sheet Had Retreated 20-60 Kilometers Behind Present Margins ~8,000 Years Ago


Lasher et al., 2017

Following deglaciation, the GrIS [Greenland Ice Sheet] retreated behind its present margins (by as much as 20-60 km in some parts of Greenland) during the HTM [Holocene Thermal Maximum] (Larsen et al., 2015; Young and Briner, 2015).”


Briner et al., 2016

The Greenland Ice Sheet retracted to its minimum extent between 5 and 3 ka [5,000 and 3,000 years ago], consistent with many sites from around Greenland depicting a switch from warm to cool conditions around that time.”

 


A Long-Term Context


Greenland has warmed 20-24 times the magnitude reached during the last century multiple times.  During these abrupt warming events (10°C to 15°C temperature rise within decades), CO2 concentrations were stable and hovered below 200 parts per million.  This indicates that the Arctic climate is not significantly influenced by CO2 variations nor human activity in general, as the past 100 years are well within the range of natural variability.


Easterbrook, 2016

In the past 500 years, Greenland temperatures have fluctuated back and forth between warming and cooling about 40 times, with changes every 25–30 years. … Comparisons of the intensity and magnitude of past warming and cooling climate changes show that the global warming experienced during the past century pales into insignificance when compared to the magnitude of profound climate reversals over the past 25,000 years. At least three warming events were 20–24 times the magnitude of warming over the past century, and four were 6–9 times the magnitude of warming over the past century.”

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July 10, 2017 at 05:20AM

A Green Economy Is Possible, But At What Cost?

A Green Economy Is Possible, But At What Cost?

via The Global Warming Policy Forum (GWPF)
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The problem with renewables lies not in capability, but in low productivity

Some US scientists have recently been conducting a rather heated argument about whether it is possible to have an economy that is powered 100 per cent by renewable (or non-fossil) energy sources. The answer, obviously, is yes.

Such economies have previously existed, and not so very long ago. Go back to 17th century Europe, and pretty much all energy production centred on the cultivation of fields, management of woodland and animal husbandry. It meant that a great deal of physical land was needed to support a population a fraction of today’s global billions.

The question is not so much whether you could recreate that sort of society. It is really whether you would want to, and that comes down to the issue of acceptable cost.

The problem with renewables lies not in whether they do the job, but in their low productivity. According to the Institute for Energy Research, the energy sector accounts for about 9 per cent of global gross domestic product. What that means is that it costs us nearly a tenth of our collective output to produce all the energy needed to run the world economy.

It is a figure that conceals technologies working at varying levels of productivity. You get a sense of the underlying picture by calculating the so-called energy return on investment for each given technology, or ratio of the income generated by that fuel or process to the capital and operating costs (excluding fuel costs) expended in actually getting the power.

They range from practically nothing for dung fires, to a 50:1 return on coal and gas, and a towering 70:1 ratio for nuclear, according to research by Professor Michael Kelly of Cambridge university. Meld them all together and the resulting blended ratio stands at about 11:1.

How would that change were the world to switch to renewables completely? Well, we can get some idea from studies of solar energy carried out in Spain for the years 2006-09. You extrapolate the earnings from a solar array over its 25-year life and then calculate the offsetting costs, including everything from land rents, maintenance, permissions to the cost of making and installing the panels. As these add up to about 40 per cent of the revenue, the energy return on investment is about 2.5:1 according to Prof Kelly.

What that’s telling us is that the proportion of our resources that would need to be devoted to energy generation would rise sharply. Compare, for instance, steel consumption sunk into gas-powered generation with that for wind turbines. A kilogramme of steel turned into a gas turbine has the capacity to generate 2 kilowatts; the same metal in a wind turbine nacelle produces just 2 watts. […]

Full post

 

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July 10, 2017 at 05:11AM

Liberal MPs Demand End to RET: Crippling Power Costs Leaves Thousands of Australian Families Totally Powerless

Liberal MPs Demand End to RET: Crippling Power Costs Leaves Thousands of Australian Families Totally Powerless

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  What happens next in Australian politics will determine the proportion of the next generation that grows up in households knowing the benefits of having electricity, as against those children who will enter life and grow up in homes deprived of what is properly considered a necessary component of a decent, civil society. Right now … Continue reading Liberal MPs Demand End to RET: Crippling Power Costs Leaves Thousands of Australian Families Totally Powerless

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July 10, 2017 at 02:31AM

EV “Range Anxiety”: Real World Issues

EV “Range Anxiety”: Real World Issues

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” … since the cost of battery packs represents a significant percentage of the initial EV purchase price, the older the battery or the more mileage on the vehicle, the greater the erosion in the car’s trade-in value.”

“‘… you can drive a Chevy Bolt the advertised 238 miles on a charge, if you can drive 60 mph.’”

“Without a very extensive and dense charging station network, when we get a large number of EVs on the road, unless they all charge at home overnight, there could be really extended waits to access charging stations. This challenge, coupled with the continuing high cost for EV battery packs for vehicles that can overcome buyer ‘range anxiety’ fears, are merely assumed away in the optimistic EV forecasts.”

The greatest drawback for the public’s acceptance of electric vehicles (EV) is “range anxiety” – running out of battery charge before reaching a charging station. A secondary concern is the high cost of the battery packs in EVs, which is what makes the cars so expensive. Auto manufacturers need government subsidies to help offset high battery costs, making EVs more price-competitive with their internal combustion engine (ICE) counterparts.

Chevy Bolt

The first moderately priced EV with long-range capacity is the Chevy Bolt, introduced by General Motors (GM-NYSE) last December.  That month, GM sold 579 vehicles in California and Oregon, the only two states where Bolts were available.

Since the start of 2017, GM has rolled out sales in other states. It now anticipates selling Bolts in every state by the end of August, four months ahead of its original schedule. The accelerated rollout is likely in response to anger among dealers and EV enthusiasts in states without access to the car. In May, GM sold 1,566 Bolts, bringing its five-month total for 2017 to 5,950 units.

Exhibit 8

Figure 1.  The 2017 Chevy Bolt Electric Car

According to details provided to auto writers, following the August nationwide rollout, GM plans a “highly targeted” national advertising campaign for the Bolt with a strong presence in online sites and very specific media where Chevy’s buyer data shows electric-car fans, advocates, and likely shoppers are concentrated. While this marketing plan sounds solid, it actually reflects the reality that EVs remain a niche product, otherwise GM would be widening its marketing campaign to general media and internet sites.

Green Car Reports documented the expense of the Chevy Bolt battery pack, although the performance of most GM EV batteries has not been a major issue so far. Depending on the state where a Bolt is purchased, GM warrants the battery’s performance for either eight years/100,000 miles, or 10 years/150,000 miles. That would seem to be sufficient time for the Bolt’s owner to enjoy its value. But since the cost of battery packs represents a significant percentage of the initial EV purchase price, the older the battery or the more mileage on the vehicle, the greater the erosion in the car’s trade-in value.

[Data point: In Beijing, one EV owner reported he purchased a three-year old car for ¥50,000 ($7,352) from a seller who had paid ¥90,000 ($13,235) net of the Chinese subsidy in 2014. Based on the history of Chinese electric vehicle subsidies, the sales price was reduced by ¥67,000 ($9,800).  Based on the original sales price and the government’s subsidy, the used car buyer paid about 32% of the EV’s unsubsidized sales price.]

The cost of the Bolt’s battery pack is much greater than for most EVs, primarily because it is larger, enabling it to go further on a charge. The US Environmental Protection Agency (EPA) credits the Bolt with a range of 238 miles. The Bolt has a 60 kilowatt-hour battery pack, compared to a Nissan Leaf’s 24 kilowatt-hour battery pack and an EPA rating of 75 miles.

Of course, the range of all EVs is a function of ambient temperatures as they impact the power output of the battery. A test conducted on a Leaf by the Idaho National Laboratory showed that at cold temperatures the mileage performance of the EV was significantly reduced. The test showed that at an average temperature of  14oF, the Leaf had a travel distance of 50 miles, while at an average of 71oF, the range increased to 91 miles.Exhibit 9

Figure 2.   Design Of Bolt Battery Pack

Because of the greater range of the Bolt given its larger battery pack, it is not surprising that it costs much more than the smaller battery pack in a Leaf. The Bolt’s replacement battery costs $15,734 compared to the $5,500 cost of a Leaf replacement battery pack.

A 2017 Nissan Leaf S model has a suggested retail price of $30,680, but this new model possesses a 30 kilowatt-hour battery pack, larger than the earlier 24 kilowatt-hour version, and a correspondingly greater range of 107 miles per charge.  The Leaf’s battery pack represents 18% of its suggested sales price.

In contrast, the larger Bolt battery pack with its substantially greater range represents 42% of the unsubsidized $37,500 sales price, or 52% of the subsidized price.  The key to success for EVs will be to bring the cost of these larger battery packs, with their greater range, down so overall vehicle costs can be reduced, which would mean government subsidies could be reduced or eliminated.

Exhibit 10

Figure 3. Location of Bolt Battery Pack

Long Trip Problems

A recent article highlighted the issues EV car owners face when trying to take long-distance trips.

Green Car Reports carried an interview with a man desperate to own a new Bolt before it would be available in his part of the country. The man lived in St. Louis and Bolts were not scheduled to be sold there before December.

Thus, he started looking for dealers in either the East or West who would sell him a new Bolt in the spring. A consideration in his dealer selection was the availability of high-speed charging stations on his route home. He wanted to use only Level 3 charging stations, which provide 160 miles of range per hour of charging, in order to  minimize the number of stops in comparison to relying on Level 2 charging stations that only provide 25 miles per hour of charging.

What he found was that there were insufficient Level 3 charging stations to get him from the West to St. Louis in the time he had available for the drive. Therefore, he focused on the East and negotiated a purchase with a dealer in Richmond, Virginia. He drove his 2007 Honda Acura RDX to the Richmond dealer and began his drive home in his new Bolt. The dealer selection was keyed to the fact Interstate-64 went between Richmond and St. Louis.

However, when he started mapping out his route, he discovered there weren’t enough fast-charging sites along the route. In fact, he found that there was not a single DC fast charging station in Kentucky.  Given his schedule, he was forced to consider alternative routes.

A southern route through Tennessee would have worked until he reached Illinois, where he faced having to make at least one Level 2 charge that provided little distance for a long stop. A northern route might have worked, but it turned an 814-mile trip into a 1,003-mile trip. All the route choices required making judgements about how far the Bolt could go on a single charge. Despite all the information offered online, the owner would know how far his Bolt could travel only once he started driving. A vehicle’s actual range depends on the driver’s approach, road conditions, and ambient temperatures.

The Bolt owner found he could schedule his charging stops with other activities such as eating or sleeping. His first charging stop was in Harrisonburg, Virginia, after 129 miles, at a 5 Guys Burgers and Fries. The second stop was 114 miles further on in Hagerstown, Maryland, at the Hagerstown Valley Mall, where he hung out and had dinner.

His final stop on the first day was at a Holiday Inn Express in Bentleyville, Pennsylvania, after another 169 miles, where there was a 240-volt Level 2 charger.  Although that was a slow charge, by spending the night at the hotel, he was fully charged the next morning.

One thing the Bolt owner learned was how to overcome “range anxiety.” He ventured information about his experience coming out of the Appalachian Mountains. Part of the route included a 9% downhill grade for three miles. By coasting downhill, when possible, and using the “Regen” feature on the Bolt EV, the vehicle gained 50 miles of range.

That’s great in areas where there are hills or mountains, but it won’t help in the Great Plains region of the country.

The Bolt trip also highlighted issues for overcoming range anxiety by controlling driving speed and the use of climate control.  According to the Bolt owner, when driving between Columbus, Ohio and Indianapolis, Indiana, he set his cruise control at 60 miles per hour (mph) and turned the climate control off every once in a while, maximizing miles per charge.

His observation was that the Bolt won’t get you 200 miles of range by driving at 70 to 75 mph, and going 80 mph is out of the question. He commented, “We set the cruise at 60 mph, and still had a little range anxiety. Imagine driving three and a half hours at 60 mph. We thought many times we were going to be run over by 18-wheelers, but it worked. So, yes, you can drive a Chevy Bolt the advertised 238 miles on a charge, if you can drive 60 mph.”

The key conclusion of the Bolt owner is that you can drive half way across the United States, but you need to do some research and planning, and also be prepared for extended stops.  This is akin to the issue of fighting the charging time versus the fill-up time at the gasoline service station.

Without a very extensive and dense charging station network, when we get a large number of EVs on the road, unless they all charge at home overnight, there could be really extended waits to access charging stations. This challenge, coupled with the continuing high cost for EV battery packs for vehicles that can overcome buyer “range anxiety” fears, are merely assumed away in the optimistic EV forecasts.

This is a reason to be cautious about assuming how quickly EVs will erode the demand for oil used in the transportation sector.

The post EV “Range Anxiety”: Real World Issues appeared first on Master Resource.

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July 10, 2017 at 01:21AM