A group of researchers at Carnegie Mellon University is trying to get a better understanding of the views of earth scientists regarding various climate change topics. They have set up an ongoing poll to do this, called Vision Prize. It’s a short (10 question) poll, covering topics like the rate of CO2 increase, predicted future temperatures, sea ice and sea level states, and hurricane frequencies. Early participants can designate a $20 donation from the group to a charity of their choice, upon completion. Please take a few minutes to help them out if qualified.

This article was originally posted on Real Climate

by Nick Sundt, reposted from the World Wildlife Fund

This article was originally posted on Climate Progress

So, it should come as very little surprise that the nuclear industry has the same ‘flexible’ view on ethics, legality and basic decency when dealing with its own people. In fact, not even the CEO of France’s nuclear giant, Areva, was safe: the Financial Times has recently revealed a catalogue of incompetence, espionage and massive financial failure (follow-up article) swirling around the French nuclear industry:

• Areva purchased a uranium mine for €1.8 billion that was valued at only €1.4 million two years earlier
• after purchase of the mine it became apparent that it contained a fraction of the uranium deposits that the Areva board believed
• a senior Areva executive was exposed as having hired a Swiss private investigation firm to spy on then Areva CEO, Anne Lauvergeon (known as ‘Atomic Anne’ in France)
• Lauvergeon alleges that her husband’s phone was hacked as part of this and is now starting legal proceedings
• the web of intrigue goes as high as the president of France, Sarkozy, who became personally involved when he forced Lauvergeon out and installed a friend of his, Henri Proglio who also happens to be CEO of EDF, one of the largest energy companies in France and the UK
• Areva have now written off almost €2 billion as a result of the failed uranium mine purchase, amid accusations of fraud – although no evidence for this has been revealed so far

This debacle is piled on top of the disastrous nuclear projects that are unravelling in Olkiluoto, Finland and Flamanville, France where Areva are trying to build their new “Nuclear Renaissance” power plants.

It all paints a picture of a desperate industry in turmoil as nuclear power continues its long-term trend of global decline, with the IEA reporting that nuclear is down 10% year-on-year as renewable energy climbs 24%. Given that the industry operates more like a crime syndicate than a legitimate business, it is a little difficult to feel any sympathy.

Along with flying atomic cars and glittering cities on the Moon, the claims of “unlimited, clean and safe energy” that is “too cheap to meter” that the nuclear lobby began promising in the 1950s have been utterly discredited. Let’s hope that the nuclear piranhas continue eating their own and finish themselves off quickly so that the planet can focus its full resources on deploying clean, safe and truly sustainable renewable energy in order to mitigate the worst of climate change.

This article was originally posted on the Green Blog under a Attribution-Noncommercial-Share Alike license.

by Kevin Benfield, cross-posted from NRDC’s Switchboard

When you look at the official US drought monitor map, you immediately see that many American cities may be in the wrong places for long-term water sustainability.  In particullar, note the presence of “long-term,” severe-to-extreme drought conditions across most of Georgia, Texas, Oklahoma, New Mexico, and Arizona.

It’s a very sobering set of facts, especially when you consider that essentially every high-growth part of the US is experiencing significant dryness.  Now let’s look at a second map, this time world-wide:

This is not just a US Sun Belt problem but a major international problem.  Here are a few facts and projections extracted from a very good summary of the issues by Jay Kimball on his blog 8020 Vision:

• By 2020, California will face a shortfall of fresh water as great as the amount that all of its cities and towns together are consuming today.
• By 2025, 1.8 billion people will live in conditions of absolute
 water scarcity, and 65 percent of the world’s population will be water stressed.
• In the US, 21 percent of agricultural irrigation is achieved by pumping groundwater at rates that exceed the water supplies ability to recharge.
• There are 66 golf courses in Palm Springs. On average, they each consume over a million gallons of water per day.
• The Ogalala aquifer, which stretches across 8 states and accounts for 40 percent of water used in Texas, will decline in volume by a staggering 52 percent between 2010 and 2060.
• Texans are probably pumping the Ogallala at about six times the rate of recharge.

With increasing rises in the temperature of the earth’s surface and atmosphere, this problem seems only likely to get worse.  The geographic details may shift from one season to another, but the long-range trend is toward further diminishing of our sources of water.  A major problem with so many environmental issues, including this one, is that the damage occurs slowly, so that people are lulled into gradually accepting additional increments of deteriorating conditions without alarm.  But that doesn’t change the facts.

Looking at the US, we’re not realistically going to shut down the whole state of Texas, along with Atlanta, Oklahoma City, Albuquerque and Phoenix.  We’re not going to stop those places from growing, either, pipe dreams of some ardent environmentalists aside.  (Nor are we going to shut down North Africa, every country bordering the Mediterranean, India, and large parts of China.)

So, what to do?

This is not going to be a post that pretends to have all the answers, many of which are going to have to come from agriculture, which is outside my expertise.  But I’ll offer a few thoughts about some answers that must also come from how we grow our cities.

For example, a decade ago, my colleague Deron Lovaas co-authored a report demonstrating how the spread of pavement caused by suburban sprawl prevents water from recharging underground reserves.  From a summary released by NRDC with its research partners American Rivers and Smart Growth America:

“In Atlanta, the nation’s most rapidly sprawling metropolitan area, recent sprawl development sends an additional 57 billion to 133 billion gallons of polluted runoff into streams and rivers each year. This water would have otherwise filtered through the soil to recharge aquifers and provide underground flows to rivers, streams and lakes.”

EPA research shows that building 1000 new homes in a watershed at an average density of eight units per acre instead of four units per acre could save as much as 27 million cubic feet of runoff per year in a typical watershed.  (Building at eight units per acre instead of one unit per acre could save 137 cubic feet of runoff per year.)

Greater average density also means less irrigated urban land per household.

In addition, I’ve been arguing for some time that “green buildings” aren’t really green if they contribute to sprawl, and that “smart growth” isn’t really smart unless it includes green buildings and infrastructure.  Doesn’t the presence of long-term drought conditions argue even more strongly for the notion that smart growth should include water-efficient technology and green infrastructure to filter rainwater before it becomes runoff?

Finally, could this be another argument in favor of reviving, rather than abandoning, our Rust Belt cities in order to take growth pressure off the Sun Belt?

– Kaid Benfield writes (almost) daily about community, development, and the environment.  For more posts, see his blog’s home page. Please also visit NRDC’s Sustainable Communities Video Channel.

This article was originally posted on Climate Progress

Have you ever given any thought to intergalactic SETI? On the face of it, the idea seems absurd — we have been doing SETI in one form or another since the days of Project Ozma and without result. If we can’t pick up radio signals from nearby stars that tell us of extraterrestrial civilizations, how could we expect to do so at distances like M31’s 2.573 million light years, not to mention even the closest galaxies beyond? Herein lies a tale, for what intergalactic SETI exposes us to is the baldness of our assumptions about the overall SETI attempt, that it is most likely to succeed using radio wavelengths, and that it may open up two-way communications with extraterrestrials. It’s the nature of these assumptions that we need to explore today.

The Visibility of a Galactic Culture

Let’s suppose, for example, that Nikolai Kardashev’s thoughts about types of civilizations are compelling enough to put to the test. A Kardashev Type III civilization is one that is able to exploit the energy resources not just of its home star but of its entire galaxy. So unimaginably beyond our present capabilities is a Kardashev Type III that we scarcely know how to describe it, but it is within the realm of reason that signs of astro-engineering on this scale might be detectable in at least nearby galaxies if such a civilization had gone to work on them. And indeed, James Annis has made such a study, concluding that neither our Milky Way nor M31 or M33, our two large, neighboring galaxies, has been transformed by the work of a Type III civilization.

Image: M33, the Triangulum Galaxy. We’ve only begun to investigate whether nearby galaxies like this one might show signs of astro-engineering on a gigantic scale. Civilizations a billion years or more older than our own might be capable of feats detectable from great distance. Credit: Adam Block/NOAO/AURA/NSF.

It should hardly be necessary to point out how preliminary such results are, and how rare such studies have been. What’s striking about Annis (and related work by Richard Carrigan and P.S. Wesson) is that these scientists are pursuing ideas that are well outside the SETI mainstream. There is a new paradigm here, one that operates without any notion of ‘contact’ and subsequent exchange of ideas between civilizations. It is a search for artifacts, for artificial structure and signs of engineering. It is all about discovery. And just as we can have no two-way conversation with Mycenaean Greece as we dig for information about the era of Agammemnon, we may with this stellar archaeology discover something just as unreachable but likewise well worth the study.

Toward a Dysonian SETI

In a recent paper, Robert Bradbury, Milan Ćirković (Astronomical Observatory, Belgrade) and George Dvorsky (Institute for Ethics and Emerging Technologies) consider whether intergalactic SETI may be an example of what they call a ‘Dysonian’ approach to SETI, one that is a ‘middle ground’ between the traditional radio-centric view (with contact implications) and the hostile reaction of SETI detractors who see no value in the enterprise whatsoever and think the money better spent elsewhere. The nod to Freeman Dyson is based on the latter’s conjecture that a truly developed society would surmount the limits of planetary living space and energy by building a Dyson shell, capturing most or all of the energy from the star near which it lived.

A Dyson sphere immediately changes the terms of SETI because it is in principle detectable, but unlike nearby radio signals (either from a beacon or as unintentional ‘leakage’ from a civilization’s activities), a Dyson shell might be spotted at great astronomical distances through its infrared signature. Carl Sagan was one of the first to pick up on the idea and ponder its implications. Dyson was much in favor of attacking the question in a disciplined way, using our astronomical tools, as he once wrote, “…to transpose the dreams of a frustrated engineer into a framework of respectable astronomy.” And here again, we have seen attempts, especially by the aforementioned Richard Carrigan, to study infrared data for signs of such Dyson constructs.

The new direction in SETI that the three authors of the new paper champion is one that employs a broader set of tools. Rather than limiting itself to radio dishes or dedicated optical facilities, it broadens our workspace for extraterrestrial civilizations to include astronomical data that can be gathered in tandem with other research projects, scanning a far wider and deeper field. In the authors’ view, Dysonian SETI also takes into account new developments in astrobiology and even extends into computer science and the possibility of post-biological intelligence. They advocate a Dysonian SETI drawing on four basic strategies to supplement older methods:

• The search for technological products, artifacts, and signatures of advanced technological civilizations.
• The study of postbiological and artificially super-intelligent evolutionary trajectories, as well as other relevant fields of future studies.
• The expansion of admissible SETI target spectrum.
• The achievement of tighter interdisciplinary contact with related astrobiological subfields (studies of Galactic habitability, biogenesis, etc.) as well as related magisteria (computer science, artificial life, evolutionary biology, philosophy of mind, etc.)

The expansion of SETI into these areas would not replace ongoing SETI methods but would significantly expand the overall process in line with the great goal of learning whether other intelligent beings share the galaxy and the nearby universe with us. The paper offers more fruitful speculation than I can fit into a single entry, so we’ll be looking at these ideas over the course of the next few days. If there really is a Great Silence, to use David Brin’s phrase, these authors argue it’s one that we can only ponder usefully if we broaden our search toward the potentially observable achievements of cultures far more advanced than our own. That study has only recently begun.

The paper is Bradbury, Ćirković and Dvorsky, “Dysonian Approach to SETI: A Fruitful Middle Ground?” JBIS Vol. 64 (2011), pp. 156-165.

This article was originally posted on Centauri Dreams

"Secretive oil billionaires attacking President Obama, with ads factcheckers say are “not tethered to the facts.” While independent watchdogs called this president’s record on ethics “unprecedented.” And America’s clean energy industry? 2.7 million jobs and “expanding rapidly.” For the first time in 13 years our dependence on foreign oil is below fifty percent. President Obama kept his promise to toughen ethics rules and strengthen America’s energy economy."

It’s interesting to note that Obama and the advertisement completely ignore to mention climate change. Instead of saying that fuel economy standards help reduce greenhouse gas emissions they are only described as a way to reduce our oil consumption. And the renewable energy investments are only mentioned in terms of job created. The advertisement also fails to mention that the dependence on foreign oil is largely due to a surge in oil and natural gas drilling and not because of a noteworthy decreased consumption.

#greenblog

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This article was originally posted on the Green Blog under a Attribution-Noncommercial-Share Alike license.

So what, other than bad journalism, explains this nonsensical headline and image from the top tech magazine Wired?

Actually, it is just bad journalism, pure and simple.  Indeed, the magazine itself clearly wanted a sensationalistic headline — and even more sensationalistic photo — to get eyeballs in this highly competitive media environment.

The story simply doesn’t justify the headline. That’s obvious from the fact that the story itself includes this summary of wind energy prospects:

Outlook: Cheaper prices for turbines should result in lower costs for wind power by 2014. Though growth has slowed since 2008, this sector is still expected to cover about a third of any increased energy consumption in the US between now and 2035.

Huh?  An energy industry that barely registered any significant U.S. capacity or generation a decade ago is now  expected to provide a third of the increased energy consumption in the next quarter century — and that’s somehow a clean-tech “bust” which warrants an exploding wind-turbine image?  Amazing (and I will repost a response to the article by a leading wind expert below).

For the record, I’m not saying the wind industry doesn’t face a near-term challenge in the face of unconventional gas and a GOP Congress unwilling to support a crucial tax credit.  Climate Progress has made clear that it does (see “Policy Uncertainty Threatens 1,600 American Wind Jobs at Vestas — and 37,000 Jobs Nationwide“).  I’m saying that there has been no bust in the industry yet, there doesn’t need to be one, and, indeed, the prospects  for the industry over the next couple of decades remain very strong, as the article itself makes clear.

I asked Eilperin about the headline and images, which I thought were completely unwarranted.  She makes clear she had nothing to do with them:

“I stand by the story, which accurately portrays some of the challenges the U.S. clean tech faces in light of the current fiscal and political climate. The piece also highlight some of the industry’s bright spots, including the fact that cheaper conventional PV panels has made the expansion of distributed solar generation and utility-scale solar projects more affordable. As many magazine readers would understand, I had no input into either the display art or the headline that accompanied the piece.”

Readers know that headlines  are the most important part of any such story, seen by  at least 10 times as many people who read it — and in the internet era, it’s likely that 20 to 100 times as many people see the headline from a  respected magazine like Wired.

Wired should retract and change the headline.

I blame the editors for this — but I don’t agree with Eilperin’s assessment of the story itself.  I think it is flawed, especially its discussion of solar energy.

The piece uses Solyndra as a stand-in for the entire US solar industry and devotes over one third of the piece to the now-bankrupt company.  But Eilperin and Wired seem completely unaware of the fact that Solyndra was always a one-of-a-kind solar play that made sense only if silicon prices stayed high.  In that sense, it was obviously part of a ”portfolio” investment strategy by DOE, a hedge against their much broader strategy, which was based on silicon prices coming down.  As Bloomberg Government made  clear in a recent analysis that received virtually no coverage in the media, “the focus on Solyndra is not proportional to its impact.”  About 87% of the DOE loan portfolio is low-risk.

You’d never know from the Wired piece that in 2010, America was a net exporter of $1.9 billion in solar products.   You’d never know that the U.S. solar industry grew 100% in 2010 and another 100% in 2011, making  it perhaps the “fastest growing” industry in America.

How does Wired make the case that the solar industry is a bust when there are ”over 100,000 Americans are working in the solar Industry.”

Promise:  … In 2010, the solar industry predicted that as many as 500,000 people would be directly or indirectly employed in the US solar sector by 2016.

Reality: As we head into 2012, the number is more like 100,000. Prices for conventional solar cells have fallen 40 percent in the past year, due largely to a flood of panels from Chinese manufacturers, which have benefited from plunging silicon prices and government support. The price drop has eviscerated the US solar manufacturing industry.

Seriously.  Apparently because there is one solar study that said we would have 500,000 jobs 4 years from now, the super-fast growing industry with 100,000 jobs is a bust.  For the record:

• It is a 2011 study .
• The 500,000 number assumes a 5-year extension of the crucial Treasury Grant Program.
• The 500,000 number is based on direct, indirect and induced jobs. Induced jobs roughly double the total!

Yet Wired still had the chutzpah  to use this image as its depiction of this staggeringly successful American industry:

Wired Caption:  ”Solar: Cheap panels from China have viscerated the US industry.”

No, the industry isn’t quite yet disemboweled.  Again, one part of the U.S. industry — manufacturing of solar cells — certainly faces a great challenge from China.

But the article  is quite confused about the impact of shale gas on solar, asserting:

Meanwhile the price of natural gas has fallen by 77 percent since 2008, and the cost of producing electricity in gas plants is down 40 percent since then. Renewables simply can’t compete.

In the case of solar, the article  utterly misses the key point that solar photovoltaics generally compete with the retail price of power, not the wholesale price.

I asked one of the leading experts on solar energy, Jigar Shah, for a response.  Shah, who founded the pioneering solar company SunEdison, writes me:

Since 2000, commercial electricity prices have gone up by almost 5% per year.  Even after the crash in wholesale prices from the financial crisis of 2008, most electricity customers are still paying much higher prices than the historic 0.6% annual rate increases in the 1980s and 90s.  The reason for this is that all of the infrastructure in the United States is “old”.  Most of the coal plants are over 40 years old and realistically cannot be run for more than another 10 to 20 years.  Most of the substations in the United States were built before everyone decided to install air conditioning.  When new natural gas plants are built, it isn’t the gas plant that is so expensive, it is the changes in the grid required to accept this new concentrated electricity source that makes up the bulk of the expenses.

With installed solar prices approaching the $2/Wdc mark for commercial rooftop systems, it is now more cost effective than retail electricity prices for over 20% of all US electricity covering 200 utilities in 29 states.  The persistence and the excitement fueled by the VC community caused over 5,000 contractors to invest their hard earned money to make solar in the local community a reality.  The final step in the solar transformation is about finance, not about technology.  In 2008, the solar industry was on the cusp of finally creating ways for common Americans to invest in solar power, to put their money where the poll numbers already suggest their heart is.  This last step was postponed by the financial crisis and is finally ready to be started again.  There are ten individual initiatives that are being led by entrepreneurs, well-known private equity managers, and large well capitalized companies all headed for the same objective, bring low risk solar assets to the public markets so that pension funds and individual investors can benefit from what Warren Buffet already knows — renewable energy projects have a higher yield and are a safer investment than corporate bonds.

In the oil, electricity, and transportation industries we have annual capital expenditures into infrastructure (not consumer products) of almost $2 Trillion per year.  The combined revenues of HP, IBM, Cisco and others that sell hardware for information infrastructure is almost 10 times less than that.  Shifting the investment into our core energy infrastructure is a multi-decade struggle that has resulted in 2010 with more money going into new renewables of $187B  while only $157B went in to new fossil fuel and nuclear generation.  Given that investment banks, law firms, and jobs care about new stuff being built all shifted their loyalties to the renewables side of the ledger.  In 2011, Bloomberg New Energy Finance said that since 2000 we have invested over $1 Trillion in clean energy broadly — $243B in 2010 alone.  This means that with current growth rates, our next Trillion will take only 4 years and by 2020 we will probably be at $1 Trillion annually — over 50% of the almost $2 Trillion needed by the whole energy industry.

Financial innovation is about building trust.  Investors need to believe that these technologies have almost zero technology risk or 100,000 hours of field testing.  They need to know that the financial products are structured in a way that clearly takes into account all of the risks.  While these steps are easier for clean energy, they are not trivial.  The efforts of the VCs and the US Government mean that we now have a set of technologies that meet this profile and have been accepted by the grand masters of finance such that they can reach $1 Trillion of annual investment by 2020.  Like the oil and gas industry, more innovation will always be possible, but meeting the final hurdle of acceptance by the finance industry is something that the oil and gas industry knows how to do.  And now so do we.

So, no, the US solar industry has not busted yet, and the future  is incredibly bright.  Would it be even brighter if  Congress were willing to extend the tax credits?  Of course, but solar is here to stay in any case.

As for wind power, Tom Gray of the American Wind Energy Association posted this response [scroll to bottom] on Wired’s website :

1) Wind is close to cost-competitive with new natural gas generation, even at today’s unsustainably low natural gas prices, and has positive offsetting benefits.

Adding wind farms to a power system helps lower fuel prices and electric rates and make them more stable and predictable.  For example, the Colorado Public Utility Commission recently approved a 25-year, 200-megawatt (MW) power purchase agreement between Xcel Energy subsidiary Public Service Co. of Colorado and NextEra Energy for power from the Limon Wind 2 project. The Colorado PUC underscored how the contract would be cost effective for consumers, saying, “the contract will save ratepayers $100 million on a net-present-value basis over its 25-year term under a base-case natural gas price scenario.”

As Bloomberg New Energy Finance lead wind analyst Justin Wu recently commented, “The public perception of wind power tends to be that it is environmentally friendly, but expensive and intermittent. That is out of date in the best locations, where generation is already cost‐competitive with fossil fuel electricity, and that will be the case for the majority of new onshore turbines installed worldwide by 2016.”

2) States that rely more on wind power have seen their electricity rates rise more slowly than states with little or no wind.

According to the Energy Information Administration (EIA), the 40 states with least wind installed (and the District of Columbia) saw electric rates rise by just over 34% between 2005 and 2010.  By contrast, the top 10 states in wind generation (with wind providing between 5.1% and 15.4% of electricity) saw an increase of less than 11%, or less than one-third as much.

Electricity rates are the result of a number of factors, so wind can’t get all the credit.  However, it makes sense that a resource with zero fuel costs, when it is available, is going to push the most expensive (and dirtiest) power plants on a utility system off line and save consumers money.

[See "The 5 States With the Most Installed Wind and Solar Power Saw the Least Increase in Electricity Prices from 2005-2010."]

3) Rep. Stearns is misinformed.  Wind energy is an American manufacturing success story. The wind industry has been a bright spot through the depths of the recession, creating one of the fastest-growing U.S. manufacturing sectors. Wind is actually insourcing a whole new manufacturing sector. Sixty percent of a wind turbine’s value is now produced here in America, compared to 25% prior to 2005. As the nonpartisan Congressional Research Service recently found, American wind manufacturing facilities have grown to almost 400 in 2010, up from as few as 30 in 2004. The key to that expansion has been the federal Production Tax Credit for wind, which has helped the companies that build wind farms to attract investment and create a market for turbines.

A recent study from Navigant Consulting finds that with stable tax policy, the wind industry can grow to nearly 100,000 American jobs in the next four years, including growing the wind manufacturing sector by one third to 46,000 American manufacturing jobs. This will keep the wind sector on track toward supporting the 500,000 jobs by 2030 envisioned in a report by the U.S. Department of Energy during the George W. Bush administration.

The development of clean, renewable energy sources such as wind power is critically important for the future of the country and everyone who uses electricity now and in the future. Wind energy is clean, abundant, and homegrown, and its cost is dropping. The case for continuing to invest in its growth through a reasonable low tax rate remains strong. And to change course now would only shut down a new U.S. manufacturing sector, just as it is starting to deliver on a large scale.

Let wind finish the job. – Tom Gray, American Wind Energy Association

So, no, there hasn’t been a bust in clean tech yet, and the industry is poised to do unbelievably well in the coming decades.  Yes, the foes of clean energy in Congress can put a crimp in the near-term growth, but the technological and marketplace reality is  very promising for renewables in the medium term.  And, of course, the ever accelerating reality of climate change means renewables are the inevitable winner in the longer term, no matter how hard their  opponents try to kill the US industry.

This article was originally posted on Climate Progress

Where is Apple in all this? Selling a lot of iPads. Where are the textbook publishers? Trying to steal the pudding of the record companies at the home for obsolete business models.

Post from: Mighty Gadget – Gadget and Technology Blog

Is this Apple’s plan for the textbook market?

Tags: Apple, education, iPad, textbook

This article was originally posted on Mighty Gadget

1. The Keystone XL pipeline would not reduce foreign oil dependency.
2. Contrary to popular opinion, Keystone XL would have increased domestic oil prices.
3. Proponents of the pipeline overstated the number of jobs that would be created.
4. Current Keystone pipeline leaked 12 times in last year.
5. And the environmental concerns about oil leaks are justified.
6. Mining tar sands would worsen global warming. Or in the words of NASA climate scientist James Hansen, be "game over for the planet."

Here is a little summary of the Keystone XL project so far:

1. Nebraska objects to the Keystone XL pipeline as they are concerned over potential oil spill accidents in the Ogallala Aquifer area, which supplies water to a large portion of US farm land. Climate activists around the US mobilized, and risked arrests in acts of civil disobedience, to raise the alarm about the environmental and climate risks of tar sands.

2. In response to Nebraska’s objections, TransCanada promises to find a better route for the pipeline and to revise the plans. But Republicans in the US congress decides to put an unreasonable deadline on the permit application to be able to gain political points in the upcoming general election. As a result of the deadline, TransCanada is not able to provide revised plan and the permit is incomplete.

3. Because TransCanada’s plans are incomplete the US government must reject the permit. If they were to approve the incomplete permit application they would set themselves up for easily winnable legal challenges by climate activists and pipeline opponents.

4. TransCanada will re-apply, and they will likely also win and get their pipeline permit a few months after the big presidential election. And considering Obama’s Keystone statement it probably won’t matter if there will be a Republican or a Democratic president in office by then.

#greenblog

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Six reasons Keystone XL was a bad deal all along
Here are six facts about the proposed Keystone XL deal that make clear why the pipeline was a bad deal for America and why it deserved to be rejected:

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This article was originally posted on the Green Blog under a Attribution-Noncommercial-Share Alike license.

by Dana Nuccitelli

At Skeptical Science, we have several recent studies which have used a number of diverse approaches to tease out the contributions of various natural and human effects to global warming.  Here we will review the results of these various studies, and a few others which we have not previously examined, to see what the scientific literature and data have to say about exactly what is causing global warming.

All of these studies, using a wide range of independent methods, provide multiple lines of evidence that humans are the dominant cause of global warming over the past century, and especially over the past 50 to 65 years (Figure 1).

Figure 1: Net human and natural percent contributions to the observed global surface warming over the past 50-65 years according to Tett et al. 2000 (T00, dark blue), Meehl et al. 2004 (M04, red), Stone et al. 2007 (S07, green), Lean and Rind 2008 (LR08, purple), Huber and Knutti 2011 (HK11, light blue), and Gillett et al. 2012 (G12, orange).  This has been added to the SkS Climate Graphics Page.

Note that the numbers provided in this summary post are best estimates from each paper.  For the sake of simplicity we have not included error bars, but we have provided links to the original research for those who would like to see the uncertainty ranges in each estimate.

A Quick Look at the Various Effects on Global Temperature

Most of the studies discussed below looked at the same few influences on global temperature, because they are the dominant effects.

As we know, human greenhouse gas (GHG) emissions warm the planet by increasing the abundance of greenhouse gases in the atmosphere, thus increasing the greenhouse effect.

Solar activity also warms or cools the planet by increasing or decreasing the amount of radiation reaching the Earth’s atmosphere and surface.

Volcanic activity generally cools the planet over short timeframes by releasing sulfate aerosols into the atmosphere, which block sunlight and reduce the amout of solar radiation reaching the surface.  However, unlike many greenhouse gases, aerosols are washed out of the atmosphere quickly, mostly after just 1-2 years.  Thus the main volcanic impact on long-term temperature changes occur when there is an extended period of particularly high or low volcanic activity.

Human aerosol emissions (primarily sulfur dioxide [SO2]) also tend to cool the planet.  The main difference is that unlike volcanoes, humans are constantly pumping large quantities of aerosols in the atmosphere by burning fossil fuels and biomatter.  This allows human aerosol emissions to have a long-term impact on temperatures, as long as we keep burning these fuels.  However, because aerosols have a number of different effects (including directly by blocking sunlight, and indirectly by seeding clouds, which both block sunlight and increase the greenhouse effect), the magnitude of their cooling effect is one of the biggest remaining uncertainties in climate science.

The El Niño Southern Oscillation (ENSO) is an oceanic cycle which alternates between El Niño and La Niña phases.  El Niño tends to shift heat from the oceans to the air, causing surface warming (but ocean cooling), whereas La Niña acts in the opposite manner.  As we’ll see, a few studies have begun examining whether ENSO has had a long-term impact on global surface temperatures.  Because it’s a cycle/oscillation, it tends to have little impact on long-term temperature changes, with the effects of La Niña cancelling out those of El Niño.

There are other effects, but GHGs and SO2 are the two largest human influences, and solar and volcanic activity and ENSO are the dominant natural influences on global temperature.  Now let’s see what the scientific literature has to say about the relative influences of each effect.

Tett et al. (2000)

Tett et al. (2000) used an “optical detection methodology” with global climate model simulations to try and match the observational data.  The inputs into the model included measurements of GHGs in the atmosphere, aerosols from volcanic eruptions, solar irradiance, human aerosol emissions, and atmospheric ozone changes (ozone is another greenhouse gas).

Tett et al. applied their model to global surface temperatures from 1897 to 1997.  Their best estimate matched the overall global warming during this period very well; however, it underestimated the warming from 1897 to 1947, and overestimated the warming from 1947 to 1997.  For this reason, during the most recent 50 year period in their study (shown in dark blue in Figure 1), the sum of their natural and human global warming contributions is larger than 100%, since their model shows more warming than observed over that period.  Over both the 50 and 100 year timeframes, Tett et al. estimated that natural factors have had a slight net cooling effect, and thus human factors have caused more than 100% of the observed global warming.

Meehl et al. (2004)

Meehl et al. 2004 used a similar approach to Tett et al., running global climate model simulations using various combinations of the different main factors which influence global temperatures (GHGs, solar activity, volcanic aerosols, human aerosols, and ozone), and comparing the results to the temperature data from 1890 to 2000.  They found that natural factors could account for most of the warming from 1910 to 1940, but simply could not account for the global warming we’ve experienced since the mid-20th Century.

Meehl et al. estimated that approximately 80% of the global warming from 1890 to 2000 was due to human effects.  Over the most recent 50 years in their study (1950-2000), natural effects combined for a net cooling, and thus like Tett et al., Meehl et al. concluded that human caused more than 100% of the global warming over that period.  Over the past 25 years, nearly 100% of the warming is due to humans, in their estimate.

Stone et al. (2007)

Stone et al. actually published two studies in 2007.  The first paper examined a set of 62 climate model simulation runs for the time period of 1940 to 2080 (the Dutch Meteorological Institute’s “Challenge Project”).  These simulations utilized measurements of GHGs, volcanic aerosols, human aerosols, and solar activity from 1940 to 2005, similar to the Tett and Meehl studies discussed above, and then used projected future emissions from the Intergovernmental Panel on Climate Change (IPCC) to project future global warming.  Whereas Tett and Meehl examined the climate response to each individual factor (and/or combinaton of factors), Stone compared these 62 climate model runs to a series of energy balance models, each representing the climate’s response to a different effect.  Over the 60 year period, Stone et al. estimated that humans caused close to 100% of the observed warming, and the natural factors had a net negative effect.  As with Stott, their model did not fit the data perfectly, though they had the opposite result, underestimating the observed warming.

In their second 2007 paper, Stone et al. updated the results from their first paper by including more climate models and more up-to-date data, and examining the timeframe of 1901 to 2005.  Over that full 104-year period, Stone et al. estimated that humans and natural effects had each contributed to approximately half of the observed warming.  Greenhouse gases contributed to 100% of the observed warming, but half of that effect was offset by the cooling effect of human aerosol emissions.  They estimated that solar and volcanic activity were responsible for 37% and 13% of the warming, respectively.

Lean and Rind (2008)

Lean and Rind 2008 used more of a statistical approach than these previous studies, using a multiple linear regression analysis.  In this approach, Lean and Rind used measurements of solar, volcanic, and human influences, as well as ENSO, and statistically matched them to the observational temperature data to achieve the best fit.  Analyzing what is left over after summing the various contributions shows whether the most significant contributions are being considered.

LR08 did this over various timeframes, and found that from 1889 to 2006, humans caused nearly 80% of the observed warming, versus approximately 12% from natural effects.  As with the previous studies discussed, this doesn’t add up to exactly 100% because the statistical fit is not perfect, and not every effect on global temperature was taken into consideration.  From both 1955 and 1979 to 2005, they estimated that humans have caused close to 100% of the observed warming.

Stott et al. (2010)

Stott et al. (S10) used a somewhat similar approach to LR08, but they used their statistical multiple linear regression results to constrain simulations from five different climate models.  S10 calculated regression coefficients for greenhouse gases, other human effects (dominated by aerosols), and natural effects (solar and volcanic), and estimated how much warming each caused over the 20th Century.  The average of the five models put the human contribution at 86% of the observed warming, and greenhouse gases at 138%, with a very small natural contribution.

Stott et al. also corrobarated their results by looking not only at global, but also regional climate changes by reviewing the body of scientific literature.  They note that human influences have been detected in changes in local temperatures, precipitation changes, atmospheric humidity, drought, Arctic ice decline, extreme heat events, ocean heat and salinity changes, and a number of other regional climate impacts.

Huber and Knutti (2011)

Huber and Knutti 2011 implemented a very interesting approach in their study, utilizing the principle of conservation of energy for the global energy budget to quantify the various contributions to the observed global warming from 1850 and 1950 to the 2000s.  Huber and Knutti took the estimated global heat content increase since 1850, calculated how much of the increase is due to various estimated radiative forcings, and partition the increase between increasing ocean heat content and outgoing longwave radiation.  More than 85% of the global heat uptake has gone into the oceans, so by including this data, their study is particularly robust.

Huber and Knutti estimate that since 1850 and 1950, approximately 75% and 100% of the observed global warming is due to human influences, respectively.

Foster and Rahmstorf (2011)

Foster and Rahmstorf (2011; FR11) implemented a very similar statistical approach to that in Lean and Rind (2008).  The main difference is that FR11 examined five different temperature data sets, including satellites, and only looked at the data from 1979 to 2010 (the satellite temperature record begins in 1979).  They also limited their analysis to the three main natural influences on global temperatures – solar and volcanic activity, and ENSO.  What remains once those three effects are filtered out is predominantly, but not entirely due to human effects.  For our purposes, we will classify this remainder as the human contribution, since FR11 removed the three largest natural effects.

Using the temperature data from the British Hadley Centre (which was used by LR08, and is the most frequently-used temperature data set in these studies), FR11 found that the three natural effects in their analysis exerted a small net cooling effect from 1979 to 2010, and therefore the leftover influence, which is predominantly due to human effects, is responsible for more than 100% of the oberved global warming over that timeframe.

One key aspect of this type of study is that it makes no assumptions about various possible solar effects on global temperatures.  Any solar effect (either direct or indirect) which is correlated to solar activity (i.e. solar irradiance, solar magnetic field [and thus galactic cosmic rays], ultraviolet [UV] radiation, etc.) is accounted for in the linear regression.  Both Lean and Rind and Foster and Rahmstorf found that solar activity has played a very small role in the observed global warming.

Gillett et al. (2012)

Similar to S10, Gillett et al. applied a statistical multiple linear regression approach to a climate model – the second generation Canadian Earth System Model (CanESM2).  They used data for human greenhouse gas and aerosol emissions, land use changes, solar activity, ozone, and volcanic aerosol emissions.  In their attribution they grouped some of the effects together into ‘natural’, ‘greenhouse gas’, and ‘other’.  The authors estimated the effects of each over three timeframes: 1851-2010, 1951-2000, and 1961-2010.  For their attributions over the most recent 50 years, we took the average of the latter two, and used their ‘other’ category as an estimate for the influence of human aerosol emissions (which will result in somewhat of an underestimate, since most ‘other’ effects are in the warming direction).

Gillett et al. estimated that over both timeframes, humans are responsible for greater than 100% of the observed warming.

Human-Caused Global Warming Consensus

The agreement between these studies using a variety of different methods and approaches is quite remarkable.  Every study concluded that over the most recent 100-150 year period examined, humans are responsible for at least 50% of the observed warming, and most estimates put the human contribution between 75 and 90% over that period (Figure 2).  Over the most recent 25-65 years, every study put the human contribution at a minimum of 98%, and most put it at well above 100%, because natural factors have probably had a small net cooling effect over recent decades (Figures 3 and 4).

Additionally, in every study over every timeframe examined, the two largest factors influencing global temperatures were human-caused: (1) GHGs, followed by (2) human aerosol emissions.  This is a dangerous situation because as we clean our air and reduce our SO2 emissions, their cooling effect will dissipate, revealing more of the underlying GHG-caused global warming trend.  Note that not all studies broke out the effects the same way (i.e. only examining ‘natural’ and not solar or volcanic effects individually), which is the reason some bars appear to be missing from Figures 2 to 4.

Figure 2: Percent contributions of various effects to the observed global surface warming over the past 100-150 years according to Tett et al. 2000 (T00, dark blue), Meehl et al. 2004 (M04, red), Stone et al. 2007 (S07, green), Lean and Rind 2008 (LR08, purple), Stott et al. 2010 (S10, gray), and Huber and Knutti 2011 (HR11, light blue).

Figure 3: Percent contributions of various effects to the observed global surface warming over the past 50-65 years according to Tett et al. 2000 (T00, dark blue), Meehl et al. 2004 (M04, red), Stone et al. 2007 (S07, green), Lean and Rind 2008 (LR08, purple), Huber and Knutti 2011 (HK11, light blue), and Gillett et al. 2012 (G12, orange).

Figure 4: Percent contributions of various effects to the observed global surface warming over the past 100-150 years according to Meehl et al. 2004 (M04, red), Lean and Rind 2008 (LR08, purple), and Foster and Rahmstorf 2011 (FR11, green).

There was a period of warming between 1910 and 1940 which was predominantly caused by increasing solar activity and an extended period of low volcanic activity, with some contribution by human effects.  However, since mid-century, solar activity has been flat, there has been moderate volcanic activity, and ENSO has had little net impact on global temperatures.  All the while GHGs kept increasing, and became the dominant effect on global temperature changes, as Figures 3 and 4 illustrate.

A wide variety of statistical and physical approaches all arrived at the same conclusion: that humans are the dominant cause of the global warming over the past century, and particularly over the past 50 years.  This robust scientific evidence is why there is a consensus among scientific experts that humans are the dominant cause of global warming.

– Dana Nuccitelli, in a piece first published at Skeptical Science.

Related Post:

• It’s “Extremely Likely That at Least 74% of Observed Warming Since 1950″ Was Manmade; It’s Highly Likely All of It Was

This article was originally posted on Climate Progress