Tag Archives: weather

Polar Vortex, Climate Change, Red Herring?

Wow, it was unusually cold last week. In a small fraction of the globe. For a couple of days. And what does that cold snap, that big wiggle in the Polar Vortex that carries high-atmospheric winds around the North Pole, imply about “climate change”, also known as “global warming”, also known as “global weirding”?

The answer is very simple. Nothing.

If you heard anyone suggest otherwise — whether they said that the extreme cold implies that there is no global warming going on, or they said that the extreme cold implies that global warming is happening — you should seriously question anything that person says when it comes to climate change. Because that person does not respect (or perhaps even understand) the difference between anecdote and evidence; between weather and climate; between a large fluctuation and a small but long-term trend. Or between media hoopla and science.

In the interest of an imperfect analogy: Let me ask you this. Are you generally happier, or less happy, than you were five years ago? Answer this as best you can.

Now let me ask you another question. Did you, within the last month, have a really, really bad day, or a really, really good one?

Does the answer to the second question have much to do with the answer to the first one?

Barring an exceptional recent disaster in your personal or professional life, the fact that, say, last Thursday your car broke down, you locked yourself out of your house, your dog vomited on the carpet and you got caught in the rain without your umbrella does not have anything to do with whether you are a happier person than you were five years ago. Being a happier person has more to do with whether you have a better job, a happier family, a better sense of self-esteem, and things like that. And even if you love your job, you know there are going to be really bad days in the office sometimes. That’s just the way it goes. We all know that.

It’s the same with daily and monthly and yearly fluctuations in the stock market compared to the slow but fairly steady century-long growth of the U.S. economy (both curves corrected for inflation.)

So why, when there’s a big fluctuation in the daily, monthly or even seasonal weather, do people jump up and down about what the implications are for the long-term trends in climate? Continue reading

Happy (Chilly) New Year

Welcome 2014! And quite a start to the year, with a cold snap that rivals anything we’ve seen in two decades. I don’t remember cold like this since the horrid winter of 1994, when the Northeastern U.S. saw snowstorms and extreme cold that alternated back and forth for weeks. Of course, when I was a child in the 1970s, such chills happened a lot more often; I remember a number of New England mornings where I awoke to a thermometer reading of -20ºFahrenheit (-29ºCelsius) [244 Kelvin].

The scariest negative temperature numbers that one hears about from the media are associated with the “wind chill”, which is a number that is supposed to measure how cold the air “feels” to your skin.  But “wind chill” is a rather subjective and controversial measure — there’s no unique way to define it, since you’ll feel differently depending on how much exposed skin you have, on your body weight, on your age and conditioning, etc.  By contrast, the temperature measured by a thermometer is defined independent of how humans feel, and experts agree on what it is and means. Oh sure, people use different scales to measure it: Fahrenheit (F), Centigrade or Celsius (C), and Kelvin (K).  But the differences are no more than the distinction between meters and feet, or between kilograms and pounds; it’s straightforward, if a bit annoying, to convert from one to the other.

So everyone agrees the temperature is and feels extremely cold, But is it, from the point of nature, really that much colder than usual? To say it another way: it was 84ºF (29ºC) in southern Florida yesterday.  How much warmer is that than the -40ºF (-40ºC) that was registered in the cold Minnesota morning?

Well, you might first think: wow, it’s a difference of 124ºF (69ºC), which sounds like a huge difference.  But is it really so huge? Continue reading

Change of Climate on the Right

There is no room for politics when we are playing for keeps. So say four Republicans, who served four Republican presidents as heads of the Evironmental Protection Agency.  The climate is changing in Washington D.C., though still more slowly than in the Arctic.

My own view? Our uncontrolled experiments on our one and only planet must be curbed.  Scientific evidence from many quarters show definitively that the Earth is warming.  Science can give us arguments, strong but not airtight, that we may be responsible (mainly via carbon emissions, and the greenhouse effect of carbon dioxide).  It cannot tell us reliably how bad the risks of a warmer Earth will be; there are too many uncertainties.  But it seems to me that these are risks we shouldn’t be taking, period.  We don’t get to mail-order another planet if we mess this one up.

A Few Items of Interest

I was sent or came across a few interesting links that relate to things covered on this blog and/or of general scientific interest.

It was announced yesterday that the European Physical Society 2013 High Energy Physics Prize was awarded to the collaboration of experimental physicists that operate the ATLAS and CMS experiments that discovered a type of Higgs particle, with special mention to Michel Della Negra, Peter Jenni, and Tejinder Virdee, for their pioneering role in the development of ATLAS and CMS.  Jenni and Virdee are both at the LHCP conference in Barcelona, which I’m also attending, and it has been a great pleasure for all of us here to be able to congratulate them in person .

One thing that came up a couple of times regarding weather forecasting (for instance, in forecasting the path of Hurricane Sandy) is that the European weather forecasters are doing a much better job of predicting storms a week in advance than U.S. forecasters are.  And I was surprised to learn that one of the the main reasons is simple: U.S. forecasters have less computing power than their European counterparts, which sounds (and is) ridiculous.  The new director of the U.S. National Weather Service, Louis Uccellini, has been successful in his goal of improving this situation, as reported here[Thanks to two readers for pointing me to this article.]

One of the possible interpretations of the new class of high-energy neutrinos reported by IceCube (see yesterday’s post) is that they come from the slow decay of a small fraction of the universe’s dark matter particles, assuming those particles have a mass of a couple of million GeV/c². [That’s much heavier than the types of dark matter particles that most people are currently looking for, in searches that I discussed in a recent article.]  I didn’t immediately mention this possibility (which is rather obvious to an expert) because I wanted a couple of days to think about it before generating a stampede or press articles.  But, not surprisingly, people who were paying more attention to what IceCube has been up to had recently written a paper on this subject[Here’s an older, related paper, but at much lower energy; maybe there are other similar papers that I don’t know about?]  At the time these authors wrote this paper, only the two highest energy neutrinos — which have energies that, within the uncertainties of the measurements, might be equal (see Figure 2 of yesterday’s post) — were publicly known.  In their paper, they predicted that (just as any expert would guess) in addition to a spike of neutrinos, all at about 1.1 million GeV, one would also find a population of lower-energy neutrinos, similar to those new neutrinos that IceCube has just announced. So yes, among many possibilities, it appears that it is possible that the new neutrinos are from decaying dark matter.  If more data reveals that there really is a spike of neutrinos with energy around 1.1 million GeV, and the currently-observed gap between the million-GeV neutrinos and the lower-energy ones barely fills in at all, then this will be extremely strong evidence in favor of this idea… though it will be another few years before the evidence could become convincing.  Conversely, if IceCube observes any neutrinos near but significantly above 1.1 million GeV, that would show there isn’t really a spike, disfavoring this particular version of the idea.

Regarding yesterday’s post, it was pointed out to me that when I wrote “The only previous example of neutrinos being used in astrophysics occurred with the discovery of neutrinos from the relatively nearby supernova, visible with the naked eye, that occurred in 1987,” I should also have noted that neutrinos were and are used to understand the interior of the sun (and vice versa).  And you could even perhaps say that atmospheric neutrinos have been used to understand cosmic rays (and vice versa.)

In sad news, in the “all-good-things-must-come-to-an-end” category, the Kepler spacecraft, which has brought us an unprecedented slew of discoveries of planets orbiting other stars, may have reached the end of the line (see for example here), at least as far as its main goals.  It’s been known for some time that its ability to orient itself precisely was in increasing peril, and it appears that it has now been lost.  Though this has occurred earlier than hoped, Kepler survived longer than its core mission was scheduled to do, and its pioneering achievements, in convincing scientists that small rocky planets not unlike our own are very common, will remain in the history books forever.  Simultaneous congratulations and condolences to the Kepler team, and good luck in getting as much as possible out of a more limited Kepler.

European Weather Model Does It Again?

We’re gearing up for another big-time storm predicted for the northeastern United States — we’ve had more than we need over recent months — so before we perhaps lose power (or you do)…

…I want to remind you that Sean Carroll and I were interviewed last night by science writer Alan Boyle.  My impression is that the conversation (which touched on issues involving the Higgs particle, dark matter, and the nature of science as a process) went well, and I hope that you enjoy it.  Just click on this link http://www.blogtalkradio.com/virtually-speaking-science/2013/02/07/sean-carroll-matt-strassler-alan-boyle , endure the commercial, and you should get the radio broadcast (just about 60 minutes).

As for that big blizzard threatening Boston with over two feet (0.6 meters) of snow, and winds over 60 miles (100 km) per hour, along with some coastal flooding, it is interesting that the European Weather Model, which did the better job on forecasting Hurricane Sandy, appears to be doing better on this one too.  The US-based Global Forecasting System may again have been a bit late to the party.  The difference in the scientific approach of the two forecasting models was described in a previous post, after Sandy, thanks to one of my readers; if you missed it then, you may find it worth a read now.

Well, it will be interesting to see how the reality plays out; but given how well the European model forecast Sandy, it would seem prudent not to underestimate this storm.  Be careful out there!

[Note Added: Julianne Dalcanton, professor of astronomy at the University of Washington, pointed me to her university colleague Cliff Mass’s article about various problems at the US National Weather Forcasting agency.  See also this article.  This is seriously disturbing stuff, if you live in the U.S.]

Another Storm Predicted

The greater New York region, having been broken into disconnected and damaged pieces by Hurricane/Nor’Easter Sandy, is still reassembling itself.  Every day sees improvements to electrical grids and mass transit and delivery of goods, though there have been many hard lessons about insufficient preparations.  Here’s an impressive challenge: over a million people and thousands of businesses lack electrical power; therefore many of them are running generators, to stay warm, keep food cold, and so forth; but the generators require fuel, typically diesel or gasoline; and so there is a greater need for fuel than usual; but a significant fraction of the petrol stations can’t pump fuel for their customers… because they lack electrical power and don’t have their own generators. These and other nasty surprises of post-storm recovery should be widely noted by policy makers and the public everywhere, especially in places that, like New York when I was a child, rarely experience disasters.

Unfortunately, another storm (a simple nor’easter) is now forecast for mid-week. While much weaker than the last, it is potentially still a dangerous situation for a region whose defenses are still being repaired.  As was the case with Sandy, the new storm was already signaled a week in advance by the ECMWF (European Center for Medium-range Weather Forecasting), the current European weather-forecasting computer program or “model”.  Confidence in the prediction has been growing, but still, predictions so far in advance do change.  Also one must keep in mind that a shift in the storm’s track of one or two hundred miles or so could very much change its impact, so the consequences of this storm, even if it occurs, are still very uncertain.  But again we are reminded, as we were last week, that weather forecasting has dramatically improved compared to thirty years ago; the possibility of a significant storm can now often be noted a week in advance.

What is this European ECMWF model? what is its competitor, the US-based GFS (Global Forecast System) model? And what about the other models that also get used?   All of these are computer programs for forecasting the weather; all of them use the same basic weather data as their starting point, and all have the same basic physics of weather built into their computer programs.  So what makes them different, and more or less reliable than one another?  I asked one of my commenters, Dan D., about this after my last post.  Here’s what he said, along with my best (and hopefully accurate) attempts at translation for less experienced readers: Continue reading

Sandy: Amazing. Science: Amazing.

My neighborhood of New York City may remain without power for a few more days, but fortunately visible signs of damage are limited — none of the widespread destruction found along the immediate coast of the city and of nearby communities, where the sea rose and swallowed up land that had not seen salt water in many decades, even centuries.  Many trees are down, and countless houses and businesses are wiped out by the sea’s wrath, even entire beach communities. The numbers of lost homes are surely in the thousands, if not more, with 100 houses alone destroyed in a runaway fire in the neighborhood of Breezy Point, cut off from firefighters by the storm’s high water.

Unfortunately, many people along the coast, lulled into complacency by the fact that last year’s Tropical Storm (formerly Hurricane) Irene was a bit less furious along the coast than was forecast, decided not to evacuate. Unfortunately indeed, because the forecast for Hurricane Sandy was worse than for Irene, and this time, there was no lucky break to make the reality of the storm significantly less severe than the worst-case prediction.  I myself know of households who decided to evacuate at the last minute and almost didn’t make it out alive, and others who rode out the storm and found themselves in considerable danger. That so many people remained in harm’s way required “first responders”, as they are termed here, mainly members of the police and fire departments, to make many rescues, quite a few of which wouldn’t have been necessary had people heeded the warnings. For risking their lives to save so many others, the first responders are widely and justifiably hailed as heroes.

Also deserving of high praise, in my view, are some of the leading politicians and other civic leaders in our region’s states and cities.  There are quite of few of them whom I don’t agree with politically and whom I personally don’t like very much, but on the whole they all seem very smart.   And in this case they understood the risks, took them seriously, and made prudent decisions to order evacuations of areas in danger and to protect public property.  They deserve a lot of credit for their non-nonsense approach.

But I feel that there’s an important story that the press is almost ignoring.  There’s another group of people, little-mentioned in the media, who probably saved more lives and property than anyone else.  I refer to the experts at the National Hurricane Center (NHC), and more generally the various branches of the National Weather Service (NWS) and its parent, the National Oceanic and Atmospheric Administration (NOAA). Continue reading

Guest Post: Anand Gnanadesikan, Oceanographer

I know Anand Gnanadesikan, professor at Johns Hopkins University’s department of Earth and Planetary Sciences, from when we were both studying physics as undergraduates in college.  He wrote something today that speaks with more authority than I could in my post earlier this morning, and it is a pleasure to make it available to you.

 

As Sandy approaches the coast I am very thankful for my former colleagues at the Geophysical Fluid Dynamics Lab who have spent decades trying to make better predictions of tropical cyclones. And the colleagues around the world who have spent decades developing the techniques of observing and modeling the physics of cyclones. Both the recurving of the storm and the high storm surge (currently already at major flood levels at a number of points between NY and DE) would have taken tens of thousands of people, at a minimum, by surprise. Kurihara’s first paper in the line of research that led to today’s prediction (http://www.gfdl.noaa.gov/bibliography/results.php?author=1061) was in 1965. It took him almost a decade to get to the first three-dimensional model of a hurricane and another couple of decades to improve the models to the point where they showed useful skill.

Just a little plug — it is important to remember that this kind of event, low-probability, high impact, is what well-run government is for. Putting together a storm-surge warning system for NY Harbor is not something that a private company is likely to do — the chances of it being used in any given 10-year period are so small as to make it a worthless investment. And the research that goes into making a forecast like this involves understanding of small-scale turbulence, understanding the transfer of radiation through the atmosphere and its interaction with multiple scatterers and absorbers, figuring out how to put weather satellites into orbit and keep them running, figuring out how to incorporate this information in computer codes, getting these codes to run reproducibly on large numbers of processors… almost all of this was accomplished by people working on the government dime.
 

Anand Gnanadesikan