Friday, August 18, 2017

When Other Things Take Precedence

First of all, I would like to apologize for taking so long to publish another blog entry.  Between teaching my summer physics class, traveling to Florida for a week, and trying to get our current house sold so we can move into a new house, I've been rather busy.  I was all set to post a review of Al Gore's latest movie An Inconvenient Sequel, but something happened this past weekend that made global warming actually seem temporarily insignificant, even to somebody who has a blog devoted to global warming.  Of course I'm talking about the events in Charlottesville, Virginia, where a series of marches that included people carrying Nazi flags and saluting Hitler led to the death of a counter-demonstrator who was standing against prejudice and bigotry.  To make a bad situation much, much worse, our President utterly failed to quickly denounce and distance himself from the groups leading the demonstrations, and in fact portrayed both sides as equivalently antagonistic. 

I started this blog to combat ignorance on a subject I know quite a bit about and care very deeply about.  Extreme ignorance takes on many forms, but whether it leads to direct acts of violence against people who are different or it compromises the long-term health of our planet, it is very dangerous.  I used to believe that ignorance would expose itself; people would simply see it for what it is, and our society as a whole has experienced too much too ever again let it gain a meaningful foothold.  I can remember when I was a graduate student at the University of Delaware in 1993, and the Ku Klux Klan were holding a rally in the heart of the town of Newark.  A lot of people attended the counter-demonstration, which significantly outnumbered the Klan rally, but a friend and I instead opted to attend an alternative rally emphasizing harmony and diversity.  Creating something positive out of a negative situation certainly has its merits, but circumstances have changed since then and made me question whether that was really the prudent thing to do.  Ignorance and hatred can spread just as easily as true knowledge and empathy can, and combating the people who propagate these things requires reaching out to people with a greater and more relentless passion.  The stakes right now are very high.  In the case of hatred and bigotry, neo-Nazis salute Trump along with Hitler and feel emboldened by the results of the 2016 election.  In the case of climate change, people who refuse to knowledge the scientific reality of global warming now dictate energy and environmental policy from the executive and legislative branches of our government.

So what, then, can we do?  For one thing, we need to call out ignorance whenever we see it, regardless of the form that it takes.  Yes, you can certainly argue that those who are ignorant of our history are doomed to repeat it.  You can also argue that those who consider Confederate soldiers to be heroes worthy of monuments are ignorant of our history.  Similarly, you can argue that people who insist that a case remains for reasonable doubt on climate change are ignorant of the decades of research that have led scientists to draw a very different conclusion.

I also believe that it is very important to not give in to our most angry and violent impulses as we resist hate and ignorance.  You don’t need to be Christian to see the disarming strength in loving your enemies, blessing them that curse you, doing good to them that hate you, and praying for them that spitefully use you.  And to quote Martin Luther King, the greatest enemy of hate and ignorance that this country has ever produced: “the nonviolent resister does not seek to humiliate or defeat the opponent but to win his friendship and understanding.”  The goal is not to defeat bad or misguided people, but to defeat bad, harmful, ignorant ideas and make all of us better people in the process.  Tell the truth.  Love, and include.  Be calm and respectful, but above all, be persistent and undaunted.

We’ll talk further soon.

Monday, June 5, 2017

Going Through Withdrawal

Last Thursday (June 1), President Donald Trump announced that he was withdrawing the United States from the Paris Agreement, a global co-operative effort to reduce the emissions of greenhouse gases in the hope of limiting global warming and reducing its effects.  He also announced that he was withdrawing from the Green Climate Fund, a United Nations effort to help the developing world build up its energy infrastructure without emitting more greenhouse gases, on the grounds that it was costing the United States “a vast fortune.”  The United States now joins Syria and Nicaragua as the only countries in the world not participating in the Agreement.  Nicaragua felt that the accord’s voluntary agreements did not go far enough, and the Syrian government’s status as an international outcast made it hard for representatives to participate in the talks.  The announcement was disappointing from my perspective as a climate scientist, to be sure, but it was not surprising.  Based on his statements in the campaign and his Executive Order on energy policy, it is clear which types of energy Trump supports and which ones he doesn’t.  Advocating for serious action to combat global warming is simply not consistent with his priorities. 

There isn't too much that needs to be said about the President’s horribly myopic decision.  You can find good point-by-point fact checks here and here, for example, so I don’t need to repeat that.  But as I mentioned in my post about the Executive Order, anybody knowledgeable about jobs in the American energy sector knows that Trump’s plans won’t actually promote job growth.  And anybody who knows the present cost of different types of energy knows that withdrawing has nothing to do with cheap energy, either.  Nor does it erase a prohibitive expense to American taxpayers.  The Paris Agreement itself did not require any binding financial commitments.  Such commitments would have required President Obama to bring the accord to the Senate for a ratification vote; given the Republican majority in the Senate, the vote would not have passed.  Obama voluntarily pledged three billion dollars, or ten dollars per citizen, to The Green Climate Fund.  As the Fund enables developing countries to build up energy infrastructure in places that don’t currently have any by using clean, renewable sources, I don't see why this cost is unreasonable.  It benefits everybody. 

What is clear is that President Trump believes that the best way to deal with the energy requirements of the 21st century is to stick with what worked in the 20th century.  Forget that cleaner energy sources than coal, and not just natural gas, are now cheaper.  Forget also that the entire rest of the world (except for Syria, whose people ironically have likely suffered far more than any other country to date from the effects of global warming) remains firmly committed to developing these energy resources further, regardless of what our President says or does.  Present economics dictates that Trump’s approach is counterproductive, and science indicates that it will do significant environmental harm.  He is essentially mortgaging the status of the United States as a leader in the the world, and the health of our planet as a whole, on obsolescent technology.

None of this should be taken as a cause for despair, however.  For one thing, the Paris Agreement was written so that withdrawing from it will take time.  Article 28 of the Accord states “At any time after three years from the date on which this Agreement has entered into force for a Party, that Party may withdraw from this Agreement by giving written notification to the Depositary.  Any such withdrawal shall take effect upon expiry of one year from the date of receipt by the Depositary of the notification of withdrawal, or on such later date as may be specified in the notification of withdrawal.”  The Accord can be withdrawn from more rapidly if Trump also withdraws the United States from the United Nations Framework Convention on Climate Change.  The Convention was entered into by President George H. W. Bush in 1992, and Democratic and Republican presidents alike have willingly participated.  Abandoning it would cement the United States as a rogue nation in the eyes of the rest of the world, and I can’t fathom that even Trump would find such a move prudent.  So barring that, the earliest date that the withdrawal can officially take effect is November 4, 2020 — the day after the next Presidential election.  A lot can happen in the meantime. 

Also, states and cities are taking the situation into their own hands.  In the wake of the withdrawal announcement, the states of New York, California, and Washington formed the U. S. Climate Alliance to maintain their part of American compliance with the Paris Agreement.  The best response to this, ultimately, is action at the statewide and local level, and this appears to be happening.  Action to combat global warming does not have to start at the top.  Right now, that is a very good thing.

Friday, May 5, 2017

The March for Science

photo by Donna Castagna-Gianelli

Saturday April 22, Earth Day, marked the global March for Science.  Scientists and non-scientists alike participated in the march in over 600 different locations around the world.  The reasons for marching were as diverse as the people participating.  For me, a college physics professor with a PhD in atmospheric science who spent sixteen years at one of the world’s major centers for climate research, it came down to the fact that we need to talk.  In a country where people with resources to spare and a vested interest in keeping people confused can send a horribly misleading book to every science teacher, we need to talk.  In a country where a series of regulations that honestly didn’t go far enough to protect our fragile planet can be undone with one stroke of a Presidential pen, we need to talk.  In a country and world where scientists can receive death threats for drawing the only conclusion the data allowed them to draw, we need to talk.  The discussion needs to be respectful and rational, of course, but scientists need to start and maintain an open dialogue with the public at large.  My fellow scientists and I cannot simply take it for granted that the results of our efforts will be accepted, understood, appreciated, and acted upon if needed.

 photo by Donna Castagna-Gianelli

I went to the march in New York City, with my wife and daughter.  From the onset, it was clear that this demonstration was different than most of the ones I’ve gone to in the past.  It wasn’t loud and angry, to be sure (notwithstanding a cascade of boos as we marched past Trump Tower).  In fact it was actually very friendly, with a tone akin more to a family gathering than to an angry protest.  We met scientists who’ve traveled to Antarctica to study the behavior of penguins.  We also met artists who made striking unicorn costumes, in the hope of raising awareness to the danger that some real creatures may become mythical in the not too distant future.

photo by Donna Castagna-Gianelli

People with a lot of experience at demonstrations might have found the atmosphere to be too polite, but it really wasn’t a bad thing.  More than anything, the march was a call for respect.  Scientists often work long hours for pay that can best be described as adequate, and the more momentum a research project has, the longer the hours become.  The results of these efforts include all the medical advances and other technology we now enjoy.  They also include greatly enhanced knowledge about the workings of the universe, including this little world on which we live.  Some of the things we’ve found out about our world are genuinely disturbing, though, and the interest of our elected government in dealing with the issue has declined even as the situation has become clearer and more urgent.

 I got my copy in my mailbox at Hofstra.  Did you get yours?

If a change in how the public views science and scientists is necessary and long overdue, scientists need to be more proactive in reaching out to the public about their work and what it means.   I felt that the March for Science was a good launching point.  It sent a simple message that we’re here, we’re human, and we’re concerned.  And above all, we need to talk.  Then, we need to keep talking.

photo by Donna Castagna-Gianelli

Thursday, April 13, 2017

Trump's Executive Order

On March 28, President Trump issued an executive order titled “Presidential Executive Order on Promoting Energy Independence and Economic Growth.”  In it, he lays out his intentions to promote the expansion of energy production from fossil fuels by removing the regulations put in place by the Obama administration to fight global warming.  While nothing in it is surprising based on the positions Trump took during the debates (which I discussed very critically in a previous post), it is worth looking at the order in detail to see what specific actions are going to be taken by our government, and what the reasons for them and actual implications really are.

The order begins by stating two premises.  The first is that “It is in the national interest to promote clean and safe development of our Nation's vast energy resources, while at the same time avoiding regulatory burdens that unnecessarily encumber energy production, constrain economic growth, and prevent job creation.  Moreover, the prudent development of these natural resources is essential to ensuring the Nation's geopolitical security.”  The second premise is that “It is further in the national interest to ensure that the Nation's electricity is affordable, reliable, safe, secure, and clean, and that it can be produced from coal, natural gas, nuclear material, flowing water, and other domestic sources, including renewable sources.”  The conclusions based on these premises are that all existing regulations will be reviewed by the government agencies under the Executive Branch, with the aim of removing any that “unduly burden the development of domestic energy resources beyond the degree necessary to protect the public interest or otherwise comply with the law.”  Regulations that are perceived to disrespect laws passed by Congress and different states, or to produce more cost than benefit, are to be put under particular scrutiny.  A directive is then given to all government agencies to review all their regulations.  The agencies have 45 days to construct a plan, 120 days to submit a draft report, and 180 days to submit a final report.

Trump then goes on to revoke and rescind a number of Obama’s executive orders and actions, most notably the Climate Action Plan and its Strategy to Reduce Methane Emissions and the Council on Environmental Quality’s guidance requiring federal agencies to take greenhouse gas emissions and global warming into account when evaluating proposed actions.  He also calls on EPA administrator Scott Pruitt to review the details of Obama’s Clean Power Plan, rescind any part of it that Pruitt deems inconsistent with the stated objectives of this executive order, and inform the Attorney General if any of the changes affect pending litigation.  Trump then calls for a detailed cost-benefit analysis of any regulations in place that relate to climate change, and replaces all of the Obama Administration’s guidelines for evaluating the social cost of greenhouse gases with a set of guidelines from the administration of George W. Bush.  The section from that document (called Circular A-4) that pertains to cost-benefit analysis begins with the following two sentences: “Your analysis should focus on benefits and costs that accrue to citizens and residents of the United States. Where you choose to evaluate a regulation that is likely to have effects beyond the borders of the United States, these effects should be reported separately.”  The Secretary of the Interior is ordered to lift all moratoria on coal leasing on federal lands, and to examine all the Obama-era regulations on the natural gas industry in order to eliminate those regulations which do not comply with this executive order’s objectives.

So what is is Trump’s intent with this executive order?  The best place to look for an answer to that is in the premises.  Much of the language in the document, starting with the first clause in the first premise, cannot be argued with on objective terms.  It is the difference in how people would define words like “necessary” and “prudent” that will lead to considerable objections.  The second clause suggests that regulations have caused burdens on the energy industry that have killed jobs, but is that actually true?  As I described in a previous post, coal has declined because of the surge in natural gas production, not from any regulations.  And the fact that natural gas production has surged indicates that the gas industry did quite well for itself in the years that Obama was President.  The second premise is more telling.  Trump announces his preference for certain forms of energy, with renewables qualifying as an “other.”  Why?  According to the 2017 U. S. Energy and Employment Report published by the Department of Energy, solar energy in 2016 employed more than four times as many people as coal in electricity generation (373,087 vs. 86,035); even when fuel production is added in, it was still more than twice as many (373,087 vs. 160,119).  Wind power employed an additional 101,738 people in the United Sates last year.  So when Trump says that prioritizing industries like coal and not renewables is about job creation it means one of three things: either he doesn’t know the DOE’s statistics on energy jobs in America, he doesn’t believe the DOE’s statistics on energy jobs in America, or he is not being honest. 

If Trump is not promoting conventional energy sources for the sake of creating jobs, is he instead doing it to promote cheaper energy?  Again, the available data suggests otherwise.  The financial institution Lazard annually publishes an assessment of the levelized cost of energy, and in 2016 they concluded that land based wind ($32-$62 per megawatt-hour or MWh, depending on location) and utility-scale solar ($46-$61 per MWh) had reached a cost level where they were usually cheaper to create the facilities and produce the energy than even natural gas ($48-$78 per MWh).  Even “dirty” coal ($60 per MWh on the low end) has trouble competing with those prices, before any added cost for regulations (or transportation and storage, for that matter) is even considered.  “Clean” coal (meaning incorporating a system to take carbon dioxide out of the emissions of burning coal and store it in the ground) would bring the price as high as $143 per MWh.  For clean coal to have any chance of being cost-competitive in the coming years, engineers would have to find a way of bringing its price down at least below what could be done with renewables generating excess energy at peak times and storing it in a battery.  At present, Lazard estimates the cost of utility-scale solar plus battery storage to be $92 per MWh.

So Trump’s apparent favoritism of the fossil fuel industry does not mesh with the current state of jobs or costs in the energy sector.  As I said when discussing his debate performance, he appears to be clinging to old narratives that aren’t true and that need to be countered with more vigor than they have been up to this point.  Now granted, I am for giving renewables preferential treatment.  I believe that there is overwhelming scientific justification for doing so, and that the economic conditions to begin the transition to a renewables-based energy sector are favorable.  It will be interesting to see what kind of counter-argument the Trump Administration makes, and whether any aspect of it is defensible.  Trump states his desire to make sure that regulations “achieve environmental improvements for the American people, and are developed through transparent processes that employ the best available peer-reviewed science and economics.”  Where global warming is concerned, the peer-reviewed science is clear and unequivocal in concluding that the Earth is getting warmer and human activity is the reason.  For our sake, I hope the President meant what he said.

To be fair, I can understand why Trump would like to show some sympathy to this country’s coal miners.  My grandfather was a coal miner from the town of Pottsville, Pennsylvania, which thrived in the early 20th century as a hub for the transportation of coal from the mines to the power generators across the state.  Collectively we all owe a huge debt to the people who extracted the coal, often at a significant expense to their own health, which powered this country and the world.  And I get that nobody wants to hear that the planet would be better off if their job didn’t exist anymore, even if — and perhaps especially if — that happens to be the truth.  I also understand that, when your career is in danger of being taken away, an amorphous promise of “training” just seems like condescension from people who aren’t directly affected.  But coal is being phased out in a number of places, not just here.  The reasons for that are many, and are economic as well as environmental.    In Australia, for example, coal mines are closing at a steady clip despite a government that’s at least as far to the right as ours currently is, and communities are indeed being affected.  What makes these closures especially damaging, according to a recent article, is the lack of time the communities have to prepare for them.  As the article indicates, the best way to mitigate the damage is with proper planning, and by making sure that the people affected are listened to in every step of the process.  Making promises to revive the coal industry, when basic economics dictates that the promises can’t be kept, will do more harm than good over the next decade for coal workers and the cities and towns that have depended on the industry.  And for the rest of us, there is simply no good mixed in with the harm.

Friday, March 17, 2017

Climate Change and the Syrian Civil War

The ongoing Civil War in Syria is both an enormous tragedy and a global crisis.  Estimates have suggested that close to half a million people have died.  The United Nations has indicated that 13.5 million Syrians need some form of humanitarian aid, including approximately five million refugees.  The Islamic State has emerged as a direct result of this conflict, taking over territory in Syria and Iraq and eventually supporting terrorist activity here in the United States.  Lots of factors have contributed to the Civil War, and it has been suggested that climate change is one of them. Showing an unequivocal link between global warming and the conflict is a challenge, but there are a couple of ways to demonstrate why such a link is plausible.  First, climate change appears to have influenced conflicts in past human history.  Second, there is strong evidence from both models and observations that climate change has influenced the recent Syrian drought.  And third, there are reasons to believe that the drought aggravated the tensions that led to the Civil War.

Science can show that the beginnings of historical periods of conflict or stability often coincide with climate shifts.  A 2011 paper, for example, used several thousand tree samples to show that the era of Roman dominance in Europe coincided with a lengthy warm, wet, and stable climate.  Subsequent instability in the climate record coincided with political upheavals, along with the barbarian advances that led to the Empire’s downfall and subsequent political chaos.  A return to stability in the climate beginning around 800 AD coincided with the establishment of lasting Medieval kingdoms.  Similarly, a 2012 paper used cave deposits to confirm the long-suspected notion that the Mayan Empire thrived during a prolonged wet period, began to struggle as the climate got drier, and then collapsed completely during a period of extended drought.  And a 2007 paper showed a statistical correlation between cycles of warfare and cycles of climate variation in Europe and China between 1400 and 1900.

So climate change often at least coincides with general historical periods of prosperity and conflict.  The conflicts typically arise from a scarcity of resources, especially water.  In the case of Syria, the nation has been wracked by a very strong, prolonged drought.  In fact, an analysis of an archive of tree ring data from the Mediterranean region has shown that the drought currently afflicting Syria has been the worst in the 900-year record.  Furthermore, modeling studies indicate that the drying of Syria is consistent with a warming world.  According to the most recent IPCC report, global warming is expected to extend the belt of dry, sinking air that shapes most of the world’s deserts further to the north, potentially affecting much of the Mediterranean region.  The historic drought in Syria over the past decade is therefore consistent with our understanding of the physics affecting Syria’s climate.

A 2015 paper titled “Climate change in the Fertile Crescent and implications of the recent Syrian drought” tied the political and climatic loose ends together.  Hafez al-Assad, father and predecessor of current Syrian leader Bashir al-Assad, ramped up Syrian agricultural production to an unsustainable degree.  This caused a steady decline in the nation’s supply of groundwater.  The lost groundwater increased Syria’s vulnerability to the historic drought, and aggravated an already precarious situation.  The loss of livelihood due to the drought led to the mass migration of rural Syrians to the peripheries of cities that were already teeming with Iraqi refugees.  It was in these peripheries that the unrest was kindled.

In short, there is very strong evidence that the drought was a major contributor to the conditions that made the Syrian Civil War possible.  While it is possible that the drought would have happened without climate change, science indicates that the warming world in which we live made such a drought more likely.  And the probability of disruptive long-term weather events occurring is only going to increase as the world continues to warm.  Furthermore, even though this conflict is taking place in a distant land, the consequences have spread globally.  Regardless of where the next disruptive event takes place, we will not be immune to its effects.

Sunday, February 12, 2017

Stepladders and pausebusters

Last week, The Mail on Sunday published an article called “Exposed: How world leaders were duped into investing billions over manipulated global warming data.”  In the article, author David Rose (whom I mentioned in my previous blog post) refers to a paper titled “Possible artifacts of data biases in the recent global surface warming hiatus,” written in 2015 by a National Oceanic and Atmospheric Administration (NOAA) research team led by Thomas Karl.  Rose suggests that the paper’s re-analysis of NOAA’s temperature records, which indicated that the warming between 1998 and 2015 was larger than initially thought, was the primary reason that the 2015 Paris agreement calling for international action to combat climate change happened.  He then goes on to say that the paper exaggerated the data because another NOAA scientist, John Bates, claimed that the publication of the paper was rushed in violation of NOAA’s rules.  The article made the rounds in the media quickly — I actually found out about it when a conservative friend of mine shared an article about the article on his Facebook feed — and Karl and his NOAA colleagues now have the increased attention of the unsympathetic House Committee on Science, Space, and Technology to contend with.  Committee Chair Lamar Smith (R-Texas) even went so far as to accuse Karl of "playing fast and loose with the data."  So what exactly happened, and what are the implications for global warming and the research behind it?

To begin to answer this question, we need go back to the temperature record.  Last week I posted a graph showing the evolution of global temperatures (from the NASA GISS data set, using bimonthly means to coincide with NOAA’s MEI data) since 1950.  There is a lot of short-term variation in the data, due largely to the cycle of El Niño and La Niña, but the overall increase is unmistakable.  The variation makes evaluating the evolution of the trend in temperature complicated, however, and very highly dependent on where you start and end the analysis.  If I were going to calculate a ballpark estimate of how the trend has changed from decade to decade, I would restrict the data to times when the El Niño cycle was mostly neutral, or when the Multivariate ENSO Index (MEI) was between +0.2 and -0.2.  I would also rule out points that were influenced by the major volcanic eruptions of El Chichon (1982) and Mt. Pinatubo (1991).  This would leave a graph that looks like this:
 Figure 1

The trend lines come from a least-squares regression of the best fit, with straight-line relationships over each decade, constrained so that each decadal line segment begins where the previous one ends.  What this shows is that the warming looks more like a stepladder than a steadily increasing parabolic curve, with some time periods warming more rapidly than others.  Is this a surprising result?  Well no, actually.  In the 1988 paper “Global Climate Changes as Forecast by the Goddard Institute for Space Studies Three-Dimensional Model,” written by a NASA GISS research team led by Jim Hansen, alternating periods of relatively rapid warming and relatively slow warming (due to natural variations beyond the El Niño cycle) can be clearly seen in the five-year running means in the model’s forecast.  (The publication of this paper coincided with Hansen’s trip to Washington to become the first scientist to testify in front of the U. S. Senate that global warming was real and required urgent action.)

So what’s the problem?  The trends displayed in Figure 1 are dependent on where I arbitrarily chose the starting and ending points.  In my graph, the trend for the decade of the 2000s is approximately 0.05ºC.  This is small compared to the 1990s (0.20ºC) and the 2010s (0.32ºC projected for the whole decade, as of the end of 2016), but not zero.  However, if you include all the data points and start the trend from the El Niño-enhanced peak in 1998, the trend over the 2000s would naturally be lower, and may even dip below zero if you choose the right endpoint.  It should be obvious (if not, see my previous post) that there are objective reasons not to start any trend analysis with the peak of a very strong El Niño, but climate science deniers created a narrative over the last decade that global warming had in fact stopped in 1998, or that at worst there was an extended “pause” or “hiatus” in the warming.  These terms were used so aggressively that they frequently appeared in the scientific literature, including the 2014 report of the Intergovernmental Panel on Climate Change (IPCC).  (Note: if you are trying to combat false narratives, do not, ever, concede to use the other side’s language.)  It was obvious by 2015 that warming had started to accelerate again, boosted partially but not entirely by another strong El Niño.  This should have rendered moot any discussion over whether there had been a pause or not.  But this is where the Karl et al. paper comes in.

The NOAA research team led by Karl worked with the NOAA temperature record.  They found that surface temperature measurements obtained on the ocean were different depending on whether they came from boats or whether they came from buoys.  When they corrected for the difference, the trend in their temperature record between 1998 and 2014 increased.  This caused an uproar — not in the climate science community, but among the community of climate science deniers, who sensed that their long-running narrative was in jeopardy.  Lamar Smith demanded that Karl produce the data and all internal communications regarding this paper.  The data were already readily available, but NOAA refused to hand over the emails.  Earlier this year, a research team led by Berkely scientist Zeke Hausfather published their results after conducting their own analysis on the NOAA data. Not only did they draw the same conclusions about the NOAA data, but confirmed that the adjustments were consistent with data from other temperature records.

That brings us to last week.  John Bates had led a team at NOAA that devised a protocol for publishing results based on NOAA data and archiving the data and the methods of analysis.  He felt that Karl had published his results before the quality of the data could be fully confirmed (it eventually was), in order to get the results out in advance of the Paris Conference.  Bates also didn’t like the manner in which the data were archived, even though plenty of data from other locations are archived similarly.  (The manner in which the data had been first archived was nothing that a researcher looking for data would object to; if anything it's very user-friendly.)  Keep in mind also that the delegates to the Paris Conference looked at hundreds of papers, and were already aware of the rapid increase in global temperatures in 2015 that was far more significant than the updated trend in the NOAA data.  But Bates recently aired his grievances in the forum for a blog that climate science deniers look at, and soon David Rose had fodder for an article, complete with much hyperbole and a comically misleading graph.  Rose repeatedly refers to the Karl et al. paper as the “pausebuster”; I had never heard that one before, but I have to admit that it’s catchy.

To make a painfully long story short, a useful paper was given extremely exaggerated importance by certain people because it messed with their narrative.  Accusations of data manipulation ensued.  These accusations have now been greatly magnified because another NOAA scientist who designed a protocol for publication decided to publicly complain, in a place where it would do maximum damage to Karl and his research team, that his process wasn’t perfectly followed.  In the end, nothing is changed about the science.  Temperatures increase more quickly over some time intervals and less quickly over others.  We already knew that.  But scientists are being accused of dishonesty, even when their analysis has been peer-reviewed and then independently verified in other peer-reviewed publications.  The accusations are coming not just from misguided bloggers and journalists, but from powerful people in Congress.

It does not have to be this way.  I am confident that most Republicans who take a long, hard look at what is going on will not continue to allow people who promote abject ignorance, to the point of witch-hunting scientists who publish results that contradict their false narratives, to represent them.  In other news this week, an older generation of Republican statesmen proposed a plan than includes a carbon tax to fight global warming.  This is exactly the kind of debate the two parties should be having: over how to address the very real problem of global warming.  Accepting reality should not be ideological.

(If you want to read a good analysis of how the data analysis process works in the context of this past week’s events, Zeke Hausfather wrote this the other day.)

Friday, February 3, 2017

Breaking the "Icy Silence"

In December, the US House of Representatives Committee on Science, Space, and Technology posted a link to an article published on the Breitbart News Network suggesting that a recent drop in land temperatures showed that the past three consecutive years of record warmth were just part of a natural fluctuation.  Both the House Committee and Breitbart are notorious for their climate change skepticism.  The House Committee is probably best known for a patently embarrassing exchange on global warming with President Obama’s science advisor John Holdren in 2014; the exchange was ruthlessly satirized by Jon Stewart on The Daily Show, but the laughs have to be tempered by the fact that these people have been given responsibility over science policy in this country.  Breibart first came to my attention in 2009 when its founder, Andrew Breitbart, posted a tweet saying “Capital Punishment for Dr James Hansen.  Climategate is High Treason.”  Jim Hansen was the director at the time of the NASA Goddard Institute for Space Studies (GISS), a major center for climate change research where I also worked.  When somebody publicly calls for the execution of your boss, you tend to notice him a bit more.  Andrew Breitbart passed away in 2012, but his successor Stephen Bannon became an instrumental figure in Donald Trump’s successful campaign last year, and now appears to rank as the new President’s most trusted advisor.  So I wasn’t expecting a whole lot of firm substance from this particular article, written by James Delingpole and titled “Global Temperatures Plunge.  Icy Silence from Climate Alarmists.”  But while there is much about the article that is misleading, there is enough of an attempt to describe actual science in the article that I think a detailed response that goes beyond a curt dismissal is warranted.

The article begins with the statement that “Global Land temperatures have plummeted by 1°C since the middle of this year — the biggest and steepest fall on record.”  There are three problems with using land temperatures over roughly half a year (keep in mind, the article came out on November 30) to infer global trends.  The first, as was pointed out by many people, is that 70% of the Earth’s surface is ocean.  The second, as a few people pointed out, is that the ocean warms and cools less quickly than land does, so the magnitude of the drop in temperature would be reduced if oceans are included.  The third problem, which I’m surprised wasn’t brought up by more people, is that 67% of the Earth’s land is in the Northern Hemisphere.  What direction would you expect Northern Hemisphere temperatures to go between the middle of the year and the end of November?  So right away you have a number presented in such a way as to make it look far more significant than it really is, and I could understand why people wouldn’t have bothered with the article any further than here.

As far as the “icy silence” from “climate alarmists” was concerned, anybody who understands how global mean temperatures fluctuate would say that a drop in global mean temperatures from the recent peak was long expected as the strong El Niño finally faded and segued into the other side of the natural cycle, called La Niña.  But what makes is this article worth examining is that, instead of ignoring the perfectly natural explanation for the temperature variation, Delingpole actually identifies the cause correctly but then mistakenly concludes that it supports the idea that there is no warming trend.  He cites another skeptical author named David Rose, who is quoted as follows:

“Big El Ninos always have an immense impact on world weather, triggering higher than normal temperatures over huge swathes of the world. The 2015-16 El Nino was probably the strongest since accurate measurements began, with the water up to 3ºC warmer than usual. 

It has now been replaced by a La Nina event – when the water in the same Pacific region turns colder than normal.  This also has worldwide impacts, driving temperatures down rather than up.

The satellite measurements over land respond quickly to El Nino and La Nina. Temperatures over the sea are also falling, but not as fast, because the sea retains heat for longer.

This means it is possible that by some yardsticks, 2016 will be declared as hot as 2015 or even slightly hotter – because El Nino did not vanish until the middle of the year.  But it is almost certain that next year, large falls will also be measured over the oceans, and by weather station thermometers on the surface of the planet – exactly as happened after the end of the last very strong El Nino in 1998. If so, some experts will be forced to eat their words.”

I’m not actually certain what experts Rose is talking about.  Most of what he says outside of the last sentence is at least defensible, although there is room for some argument on the details.  (2016 appears to have been more than slightly warmer than 2015, for example.)  To illustrate the connection between the El Niño/La Ninã cycle (generally referred to in the scientific community as the El Niño Southern Oscillation, or ENSO) and global mean temperature, I’m going to show a few graphs.

Figure 1

Figure 1 contains the bimonthly mean anomalies, measured relative to the 1951-1980 mean, of global temperatures in the GISS data set.  The temperature curve is not a smooth, steady rise, but rather a series of peaks and relative minima oscillating back and forth around a general trend.  The most pronounced peak is indeed the most recent one, reaching a bimonthly mean value of 1.33 ºC above the 1951-1980 mean in February/March 2016.  The temperature anomaly dropped over half a degree back to 0.80ºC in June/July, which is pretty steep over a short period of time, but it has actually gone up a bit since then.

Figure 2

Figure 2 shows the corresponding bimonthly mean plot of a quantity defined by the National Oceanic and Atmospheric Administration (NOAA) as the Multivariate ENSO Index (MEI).  The mathematics of calculating the MEI is complicated, but it revolves around measurements of six different weather-related quantities in the tropical Pacific, and then defining the variance in these quantities relative to median conditions (defined as an MEI of 0).  The high positive values correspond to El Niño events, while the strongly negative values correspond to La Niña events.  As you can see, many of the temperature spikes in Figure 1 coincide with El Niño events, and many of the relative minima coincide with La Niña events.  This is why scientists consider the ENSO cycle to be the dominant source of short-term, natural variations in the global temperature record.

However, while the 2015-2016 El Niño event is among the strongest on record, the MEI data suggest that it was not stronger than the one in 1998.  That particular El Niño event produced its own sharp spike in the global temperature record.  It has also produced a large amount of misunderstanding of how global mean temperatures work, as skeptics have spent much of the last decade or so declaring the 1998 peak as the point where global warming stopped.  It should be clear enough from Figure 1 that there is more at work than the cyclical El Niño variations.  The highest bimonthly mean temperature anomaly recorded in 1998, a stronger El Niño than the most recent one according to the MEI data, was 0.75ºC.  Not only is that nearly 0.6ºC cooler than the most recent peak in the temperature anomaly from last year, but the 1998 peak was cooler than the planet is right now, even after the large drop.

As for the drop, the 2015-2016 El Niño has certainly ended, but the present state is closer to neutral than to a full-blown La Niña event.  This suggests that ENSO-neutral conditions presently result in a temperature anomaly at, or maybe a little bit above, 0.80ºC.  Were this state of general neutrality to continue for the rest of the year, 2017 would wind up comfortably being the third warmest on record, but that ultimately depends on whether or not a strong La Niña ultimately happens.

So does that mean, as Delingpole concludes in his article, that “The last three years may eventually come to be seen as the final death rattle of the global warming scare”?  No, of course not.  The overall trend in the temperature anomaly data continues to be positive.  The trend may appear larger or smaller at different times due to natural fluctuations, but it is there just the same.  If ENSO were the dominant influence on global mean temperatures without any additional warming trend, then the temperature anomaly from this past year would most likely not be higher at all than the one in 1998, much less 0.6ºC higher.

(Incidentally, I told my climate-related classes in 2015 that it would only be a matter of time before the same people who insist on using the peak of the strong 1998 El Niño as the starting point in their analysis of subsequent temperature trends would start publicly dismissing the much greater peak presently in the temperature record on account of its association with a strong El Niño.  And here you go.)