New survey updates polar ice sheet loss figures

[Crayz9000]

This just hit Slashdot today.

http://www.nature.com/news/grim-picture ... 1.11921#b1

A global team of researchers has come up with the 'most accurate estimate' yet for melting of the polar ice sheets, ending decades of uncertainty about whether the sheets will melt further or actually gain mass in the face of climate change.

The ice sheets in Greenland and Antarctica are melting at an ever-quickening pace. Since 1992, they have contributed 11 millimetres — or one-fifth — of the total global sea-level rise, say researchers. The two polar regions are now losing mass three times faster than they were 20 years ago, with Greenland alone now shedding ice at about five times the rate observed in the early 1990s.

This latest estimate1, published this week in Science, draws on up to 32 years of ice-sheet simulations and 20 years of satellite data.

With climate change, some scientists had expected that warmer air would increase snowfall over Antarctica, and that this would largely offset the increased ice loss from Greenland caused by warmer seas. In recent years, however, a number of studies have shown2–4 that both ice sheets are losing mass at an alarming rate, as ice streams speed up their seaward journeys and more and bigger icebergs are discharged into the ocean.

Estimates have not always been consistent with each other, however5, leaving scientists concerned about their reliability. In its 2007 report, the Intergovernmental Panel on Climate Change (IPCC) declined to set an upper limit on the extent to which ice loss from Antarctica could contribute to sea-level rise, saying the science was too uncertain6.

The latest study “moves Antarctica from a position of relative uncertainty in terms of its ice loss to one where we are now certain that it is losing ice”, says Andrew Shepherd, first author of the study and professor of Earth observation at the University of Leeds, UK.

Scientists use four techniques to gauge whether the ice caps are gaining or losing mass. Two techniques involve using either lasers or radars on satellites to measure changes in the surface elevation of the ice; another uses a method known as input-output modelling to represent regional changes in snowfall and ice melt; and the fourth measures changes in ice-sheet mass from space using the Gravity Recovery and Climate Experiment (GRACE) mission satellites.
Compensatory snowfall

The international team of 47 experts led by Shepherd analysed data collected by these methods from almost 30 previous ice-sheet studies, including 20 years of data from 10 different satellite missions and 32 years of model data on surface mass balance — the difference in the weight of the ice sheet gained through snowfall and lost through melting of the ice sheets.

The result is an estimate “two to three times more accurate than that in the last IPCC report”, says Shepherd.

Riccardo Riva, a geoscientist at Delft University of Technology in the Netherlands, independent of the study, says: “It provides a solid answer to the whole scientific community and the general public that over the last 20 years, the polar ice sheets did contribute to global mean sea-level rise by a significant amount.”

Yet large uncertainties remain, especially for Antarctica. The good news, says Riva, is that Antarctica is not losing ice as rapidly as suggested by many recent studies. What’s more, snowfall in east Antarctica still seems to be compensating for some — but not all — of the melting elsewhere in Antarctica.

It is unclear how these trends, such as ice loss from Greenland, will evolve, says Ian Joughin, one of the paper's co-authors and a satellite expert at the University of Washington in Seattle. “It really remains unclear whether such losses will decline, whether they’ll level off or they’ll accelerate further,” he says.

Since the evidence shows that the planet is warming without a doubt, the only question is how much our actions factor into it, vs geological processes and solar processes. During the discussion on Slashdot, someone included a link to the USGS's volcanic process site to refute one of the common claims that volcanic CO2 output exceeds artificial CO2 output.

http://volcanoes.usgs.gov/hazards/gas/climate.php

Interestingly enough, the figures here completely refute the California environmentalists' irrational focus on light vehicles as a major pollution source.

Figures in gigatons (1 bn metric tons) per year
Global volcanic emissions (highest preferred estimate) 0.26
Anthropogenic CO2 in 2010 (projected) 35.0
Light-duty vehicles (cars/trucks) 3.0
Approximately 24 1000-megawatt coal-fired power stations * 0.22
* Equal to 2% of the world's coal-fired electricity-generating capacity.

Running quick numbers, this means that coal-fired power stations account for roughly 11 gigatons of global artificial CO2 output, or 31%. Light duty vehicles, by comparison, only account for 8.5%.

This of course means that if the green nuts would get off their high horse and back nuclear power in the interest of eliminating coal-fired power plants, we could potentially remove close to a third of annual manmade CO2 from the equation. But of course they won't support that, because nuclear is EVIL.

[D.Turtle]

10% of total output is not a major source?

In addition, you will provide a source showing that it if only environmentalists wouldn't exist, then all coal plants world-wide would immediately be replaced by nuclear power plants.

[Crayz9000]

I'm not saying that cars are not a major pollution source at all. It's just that when compared to coal fired power plants, they comprise less than one third in proportion. Ideally we want to move away from fossil fuels in cars as well, but right now moving to electric vehicles means increasing the load on... you guessed it, coal fired power plants. Which is a step backward. The environmentalist movement seems to be completely blind to this fact in their zeal to rid the world of nuclear power.

My analogy is heavily simplified by virtue of being a napkin calculation. I did say they were quick numbers.

I will also note that not all environmentalists are dead-set against nuclear power. In fact, a while back the co-founder of Greenpeace was interviewed by Wired and now strongly supports nuclear power. I'm merely lamenting the fact that the nuclear environmentalist movement isn't catching on with the general environmentalist movement.

Finally, I accept the fact that we will be stuck with coal baseline power for years to come. It takes a significant amount of time to build new reactors, so even if all environmentalists and their supporting politicians did a complete about-face today, we would be talking at least 20 years before we saw new reactors starting to replace coal plants. However, the about-face would provide the political clout to grease the wheels on the process, so to speak.

[Guardsman Bass]

Christ, is this really going to turn into the hundredth shitfest over nuclear power?

In any case, this news sucks. Even if it doesn't seem like much, small rises in sea level can make flooding drastically worse in severe storms, cause salt water to get into wetlands and freshwater aquifers, and cause complications like extra flooding in the subway systems of coastal cities.

[D.Turtle]

I'm not saying that cars are not a major pollution source at all. It's just that when compared to coal fired power plants, they comprise less than one third in proportion. Ideally we want to move away from fossil fuels in cars as well, but right now moving to electric vehicles means increasing the load on... you guessed it, coal fired power plants. Which is a step backward. The environmentalist movement seems to be completely blind to this fact in their zeal to rid the world of nuclear power.

My analogy is heavily simplified by virtue of being a napkin calculation. I did say they were quick numbers.

I will also note that not all environmentalists are dead-set against nuclear power. In fact, a while back the co-founder of Greenpeace was interviewed by Wired and now strongly supports nuclear power. I'm merely lamenting the fact that the nuclear environmentalist movement isn't catching on with the general environmentalist movement.

Finally, I accept the fact that we will be stuck with coal baseline power for years to come. It takes a significant amount of time to build new reactors, so even if all environmentalists and their supporting politicians did a complete about-face today, we would be talking at least 20 years before we saw new reactors starting to replace coal plants. However, the about-face would provide the political clout to grease the wheels on the process, so to speak.

Thanks.

Now, we get to the next problem with your analysis. The numbers you (or rather the site) provided are for global emissions. The breakdown by sector, however, varies greatly across - among other things - countries. For example, in the US (since you referred to California environmentalists) the breakdown by source and sector looks like this (for 2010):

Well, if that isn't the transportation sector emitting as much CO2 equivalent as coal plants for electricity.
And for California specifically, transportations is by far the largest sector:

[Crayz9000]

While California's certainly ahead of the curve in that graph, I see they conveniently label "imported electricity" but without knowing how they determined those numbers, I'm not entirely sure I can trust it. I do note that the amount of CO2 from imported electricity was steadily rising over that 14-year period.

Looking at the national picture, it clearly shows that the lion's share of coal CO2 is tied to the energy sector, which almost equals the amount of petroleum CO2 from transportation in the US. My point still stands that replacing coal with nuclear would allow the eventual removal of coal-produced CO2 from the equation, while simultaneously allowing vehicles to shift from petroleum to electricity more easily.

In other words, given about 40 years of future development with full support for nuclear power in the US, and assuming that the proportions between residential, commercial, industrial, and transportation hold equal, I believe it would be safe to say that with a nuclear baseline grid in place and natural gas or petroleum byproducts such as LPG for peak loads, it's not entirely inconceivable to see the replacement of at least 50% of emissions currently produced by coal and petroleum combined (by the energy and transportation sectors, respectively) with nuclear-produced energy. Note that this best-case scenario guess assumes that we can only replace 80% of petroleum-fueled transportation with electric-powered transportation. I'm also unsure what proportion of the transportation sector is comprised of air traffic, since that cannot be switched to any sort of clean energy without massive drawbacks (hydrogen being a total bitch to handle, for instance).

Again, I know I'm mostly pulling these numbers out of my ass. This is an educated guess at best, relying on many best case assumptions to work properly. Most of this stems from the fact that based on the evidence I've seen, nuclear power is the only viable baseline power substitute for coal power.

[D.Turtle]

While California's certainly ahead of the curve in that graph, I see they conveniently label "imported electricity" but without knowing how they determined those numbers, I'm not entirely sure I can trust it. I do note that the amount of CO2 from imported electricity was steadily rising over that 14-year period.

How about data from the US Energy information administration, where I found some more up-to-date figures:

Looking at the national picture, it clearly shows that the lion's share of coal CO2 is tied to the energy sector, which almost equals the amount of petroleum CO2 from transportation in the US. My point still stands that replacing coal with nuclear would allow the eventual removal of coal-produced CO2 from the equation, while simultaneously allowing vehicles to shift from petroleum to electricity more easily.

Oh, definitely removing coal from the equation is essential. My problem with your statement was that you were dismissing transportation as a sector with major relevance with regards to future CO2 reduction.

In other words, given about 40 years of future development with full support for nuclear power in the US, and assuming that the proportions between residential, commercial, industrial, and transportation hold equal, I believe it would be safe to say that with a nuclear baseline grid in place and natural gas or petroleum byproducts such as LPG for peak loads, it's not entirely inconceivable to see the replacement of at least 50% of emissions currently produced by coal and petroleum combined (by the energy and transportation sectors, respectively) with nuclear-produced energy. Note that this best-case scenario guess assumes that we can only replace 80% of petroleum-fueled transportation with electric-powered transportation. I'm also unsure what proportion of the transportation sector is comprised of air traffic, since that cannot be switched to any sort of clean energy without massive drawbacks (hydrogen being a total bitch to handle, for instance).

Again, I know I'm mostly pulling these numbers out of my ass. This is an educated guess at best, relying on many best case assumptions to work properly. Most of this stems from the fact that based on the evidence I've seen, nuclear power is the only viable baseline power substitute for coal power.

Well, one alternative source to coal is natural gas, which is a lot less CO2 intensive than coal plants. Of course that can only be a stop-gag measure in order to get old and inefficient coal plants off the grid as quickly as possible (and why it makes sense to build new fossil fuel plants even while transitioning to a CO2 neutral energy system). One huge problem with widespread nuclear adoption is that it requires very high tech infrastructure and highly specialized and trained operators in order to be safely run.

Oh, as for air traffic:

(From the Annual Energy Review 2011)

Edit: My overall point is this: Looking at global consumption and from there mocking local priorities is stupid, if the local situation is very different from the global situation. This is the vase with regards to the US vs global, but also California vs US. Telling California environmentalists that their priority should be getting rid of coal is ridiculous as there is almost no coal in California.

[Crayz9000]

I can agree with pretty much all of your points.

I think our main difference stems from the fact that since California effectively "drives" the US emissions policies, their focus on motor vehicle emissions (while appropriate for California) is inappropriate for the nation as a whole. Without moving our baseline energy away from coal, mandating electric vehicles across the US is going to wind up raising CO2 output without having a nuclear infrastructure in place.

I did mention natural gas and petroleum byproducts like LPG, you may note. An all-nuclear grid is not feasible with today's technology because of peak energy demands. We would therefore need CNG/LPG powered plants to make up the difference during those times.

[D.Turtle]

I haven't seen any major push for an immediate shift to electric vehicles (not to mention mandating them). Instead what I have seen is calls for quickly increasing required gas mileage of vehicles - something that is relatively easily done, and would have a very large effect.

Lets put it this way: Transportation is roughly a third of CO2 output in the US. Doubling gas mileage would therefore mean roughly a decrease of one sixth of the US CO2 output. That is a lot. The US currently emits roughly one sixth of the global CO2 emissions. Therefore, doubling the gas mileage would reduce global output by roughly 3%, or in another comparison: It would reduce CO2 output by more than Germany as a whole emits in a year.

Improving gas mileage is something easily done (and mandated), while having a quite significant impact on global CO2 emissions.

Is it sufficient? No. Does it help? Yes.

Its not like it is only possible to pursue one goal at a time. Therefore, it is quite sensible and effective to put a focus on motor vehicle emissions.

[Crayz9000]

Believe it or not, California mandated in 1990 that 10% of all vehicles sold by the year 2003 must produce zero emissions (i.e. they should be electric vehicles). They were forced to amend the mandate when it became obvious that the goal was unrealistic, and they will probably do so again in the future. Ref: PPIC study of the law

I don't really have problems with gas mileage mandates aside from the fact that they tend to force automakers to concentrate on loopholes. Plus, the law of diminishing returns kicks in (we're already starting to see it rear its ugly head; just look at the fact that mileage improvements to the Prius have been rather marginal over the entire run of the car). It's rather the other associated legislation that tends to accompany any emissions bill.

For instance, do you know that in California it is illegal for a private party to modify their own vehicle to run on a cleaner burning fuel such as CNG or LPG? Any conversions must be done on NEW vehicles by a licensed conversion shop using CARB-approved equipment. CARB and EPA approval are expensive, hard to obtain, and one of the LPG component manufacturers I spoke to said they only maintain certificates for the current year's products because of the expenses involved. Because the EPA modelled their guidelines after the CARB guidelines, it is likewise illegal in the other 49 states -- but the EPA at least provides a "testing" exemption that private parties can use for their own vehicles.

[Irbis]

For instance, do you know that in California it is illegal for a private party to modify their own vehicle to run on a cleaner burning fuel such as CNG or LPG? Any conversions must be done on NEW vehicles by a licensed conversion shop using CARB-approved equipment. CARB and EPA approval are expensive, hard to obtain, and one of the LPG component manufacturers I spoke to said they only maintain certificates for the current year's products because of the expenses involved.

Oh? That's kinda messed up - in Poland, for comparison, 3 out of 20 million cars run on Autogas, with no subsidies on modifications or anything, people converting privately because it costs about half of normal fuel. All you need to do is take car to certified shop, pick kit from one of the V generations, from cheapest but inefficient to modern ones, wait a day or two, that's all. In fact, so many shops do the conversion you're encouraged to look which are most reputable.

[D.Turtle]

Believe it or not, California mandated in 1990 that 10% of all vehicles sold by the year 2003 must produce zero emissions (i.e. they should be electric vehicles). They were forced to amend the mandate when it became obvious that the goal was unrealistic, and they will probably do so again in the future. Ref: PPIC study of the law

That is fucked up - learn something new every day. At least they replaced it with something more sensible.

I don't really have problems with gas mileage mandates aside from the fact that they tend to force automakers to concentrate on loopholes. Plus, the law of diminishing returns kicks in (we're already starting to see it rear its ugly head; just look at the fact that mileage improvements to the Prius have been rather marginal over the entire run of the car). It's rather the other associated legislation that tends to accompany any emissions bill.

While cars like the Prius might be running into diminishing return problems. the fact of the matter is that the vast majority of vehicles in the US are far, far, far away from getting close to a point where diminishing returns might be kicking in. Getting everything to the level of a Prius would be a HUGE improvement.

For instance, do you know that in California it is illegal for a private party to modify their own vehicle to run on a cleaner burning fuel such as CNG or LPG? Any conversions must be done on NEW vehicles by a licensed conversion shop using CARB-approved equipment. CARB and EPA approval are expensive, hard to obtain, and one of the LPG component manufacturers I spoke to said they only maintain certificates for the current year's products because of the expenses involved. Because the EPA modelled their guidelines after the CARB guidelines, it is likewise illegal in the other 49 states -- but the EPA at least provides a "testing" exemption that private parties can use for their own vehicles.

Well, that is really fucked up - however that is not what I can find on the Internet. For example, this site says:

"Under current California regulations, conversion of emission-controlled vehicles with retrofit systems to operate on alternative fuels, such as propane and natural gas, in lieu of the original gasoline or diesel fuel is only allowed if the retrofit systems have been evaluated and certified by the Air Resources Board. The certification must be obtained by the manufacturer of the retrofit system and is issued by the Air Resources Board once the manufacturer demonstrates compliance with the emission, warranty, and durability requirements."

So, the retrofit system has to be certified, but can be applied to any vehicle, not just new ones.

[aerius]

If you want to ballpark CO2 emissions from cars & trucks you just need to figure out out much diesel and gasoline gets burned in a year. So more or less, find the oil consumption figures for the year, then adjust for the refinery crack which is about 50% gasoline and 25% diesel per barrel of oil, then punch it in to the CO2 emissions chart after doing your unit conversions. Last time I checked oil consumption is 87-88 million barrels per day, my shitty calculator doesn't like big numbers so someone else can do the math.

[Crayz9000]

This site has a better summary of the problems:
http://www.ngvamerica.org/gov_policy/fe ... arket.html

Anti-tampering provisions and policy guidance
EPA policy has always required manufacturers of conversion equipment to ensure that their systems do not degrade the emissions performance of motor vehicles. This policy directive was first set out in EPA's Mobile Source Enforcement Memorandum 1A, which is based on the Clean Air Act's prohibition against tampering with motor vehicle emissions, section 203(a), 42 U.S.C. 7522(a). Section 203(a) makes it illegal to install any component or part if it defeats or "render inoperative any device or element of design installed" on a certified motor vehicle or engine. EPA's stated purpose in issuing Memorandum 1A was to "provide criteria by which dealers [and now conversion manufacturers] can determine in advance that certain of their acts do not constitute tampering." Memorandum 1A requires that manufacturers have a "reasonable basis" for believing that their equipment or actions will not increase emissions. A manufacturer could satisfy the "reasonable basis" requirement if "emissions tests… have been performed according to testing procedures prescribed in 40 C.F.R. section 85" and if the tests show "that the act [e.g., conversion] does not cause similar vehicles or engines to fail to meet the applicable emission standards."

Initially, Memorandum 1A acted to insulate manufactures from tampering violations as long as they complied with the testing procedures outlined above. However, compliance with Memorandum 1A never relieved manufactures of responsibility for in-use emissions performance, durability, and compliance with useful-life emission standards.

Policy change
In September 1997, EPA issued an addendum to Memorandum 1A. The addendum altered EPA policy with respect to conversions by requiring manufacturers to start certifying their systems in order to protect themselves from tampering violations. Under the new guidance, the only way manufacturers can satisfy the "reasonable basis" test is full certification (either EPA or CARB). The policy change was prompted by evidence it collected that suggested conversion systems were increasing vehicle emissions. EPA believed that the only way to effectively ensure conversions were not increasing emissions was to subject them to full certification. This policy has since evolved with the latest changes coming in March 2011 in the form of the new streamlined regulations, discussed above.

California’s Air Resources Board (CARB)
California has its own certification rules for alternative fuel conversion systems. See the Final Regulatory Order for certification requirements. These rules also impact the sale and use of conversion systems in some but not all of the states that have adopted CARB’s motor vehicle regulations (e.g., Maryland and New York require CARB certified systems). Pennsylvania and New Jersey have issued guidance indicating that they will accept EPA certified systems in addition to CARB systems. CARB’s certification requirements for aftermarket systems have not been updated since 1995 and are essentially obsolete. As a result, manufacturers seeking CARB certification for conversion systems instead use the certification rules for new vehicles. Complying with CARB’s rules is very costly and time-consuming, especially for bi-fuel vehicles. As a result, manufacturers are currently only certifying dedicated NGV systems; although, a number of manufacturers have indicated that they plan to seek certification for bi-fuel conversions.

The crux of the matter is the anti-tampering wording presented in the Clean Air Act. In the '70s it wasn't too much of an issue since the equipment was designed to bolt without requiring any of the stock emissions equipment to be disabled. Things started to get worse in the 1980s with the computerized emissions systems, since switching to propane for example required shutting off the fuel injectors. The OBDII standard made things even worse, since an OBDII emissions test hooks the computer's diagnostic output to the smog testing equipment to make sure that all the onboard sensors are working properly. If the injectors happen to be disabled, the computer's going to be throwing all sorts of trouble codes out which means the car automatically fails. Since there is almost no standardization regarding ECM computers with the exception of the OBDII interface itself, every conversion kit has to be tailored specifically to the vehicle's model year, with the end result that most equipment manufacturers gave up making conversion kits for the general public and instead focused on the more lucrative fleet conversion industry.

[D.Turtle]

Thats interesting information. Thanks.