Monthly Archives: March 2015

With Global Warming, Will Cold Outbreaks Be Less Common?

Maybe, maybe not. There is a new paper that looks at what climate scientists call “synoptic midlatitude temperature variability” and the rest of us call “cold snaps” and “heat waves.” The term “synoptic” simply means over a reasonably large area like you might expect a cold snap or heat wave to be. Specifically, the paper (Physics of Changes in Synoptic Midlatitude Temperature Variability, by Tapio Schneider, Tobias Bischoff and Hanna Plotka, published in Journal of Climate) concludes that as human-caused greenhouse gas pollution increases, the frequency of cold snaps in the northern hemisphere will go down. Naturally, as temperatures warm up we would expect the highs to get higher, the averages to be higher, and the lows to be higher as well (and thus fewer cold spells). But the new research actually argues that the cold spells (the cold extremes at synoptic spacial scales) will become even less common. This is potentially controversial and conflicts with other recently published research.

The paper is rather technical so, I’ll give you the abstract so you can go take a class in climate science, then come back and read it:

This paper examines the physical processes controlling how synoptic midlatitude temperature variability near the surface changes with climate. Because synoptic temperature variability is primarily generated by advection, it can be related to mean potential temperature gradients and mixing lengths near the surface. Scaling arguments show that the reduction of meridional potential temperature gradients that accompanies polar amplification of global warming leads to a reduction of the synoptic temperature variance near the surface. This is confirmed in simulations of a wide range of climates with an idealized GCM. In comprehensive climate simulations (CMIP5), Arctic amplification of global warming similarly entails a large-scale reduction of the near-surface temperature variance in Northern Hemisphere midlatitudes, especially in winter. The probability density functions of synoptic near-surface temperature variations in midlatitudes are statistically indistinguishable from Gaussian, both in reanalysis data and in a range of climates simulated with idealized and comprehensive GCMs. This indicates that changes in mean values and variances suffice to account for changes even in extreme synoptic temperature variations. Taken together, the results indicate that Arctic amplification of global warming leads to even less frequent cold outbreaks in Northern Hemisphere winter than a shift toward a warmer mean climate implies by itself.

Why is this controversial? Because we have seen research in recent years indicating that with Arctic Amplification (the Arctic getting relatively warmer than the rest of the planet as global warming commences) the manner in which warm air is redistributed from sun-facing Equatorial regions towards the poles changes, which in turn changes the behavior of the Polar jet stream. Rather than being relatively straight as it rushes around the globe, separating temperate and sub-polar regions (and defining the boundaries of trade winds, and moving along storms) it is thought that the jet stream has become more often very curvy, forming what are called Rossby waves. These waves, recent research has suggested, can become stationary and the wind within the waves moves relatively slowly. A curvy jet stream forms meteorological features such as the “ridiculously resilient ridge” which has brought California nearly continuous dry conditions for at least two years now, resulting in an unprecedented drought. A curvy jet stream also forms meteorological features called “troughs” such as the excursion known last year (incorrectly) as the Polar Vortex, which also returned in less severe form this year; a bend in the jet stream that brings polar air farther south than usual, causing a synoptic cold spell of extensive duration. These changes in the jet stream also seem to have brought some unusual winter weather to the American Southeast last year, and have been implicated in steering Super Storm Sandy into the US Northeast a few years ago. And that flood in Boulder, and the flood in Calgary, and the June Of All Rain here in Minnesota last year, and so on. This is the main global warming caused change in weather systems responsible for what has been termed “Weather Whiplash” and may rank up there with increased sea surface temperatures as factors underlying the observable, day to day effects of human caused climate disruption.

I’ve talked about jet streams, Rossby waves, and such in a few places:

Even more recently was a paper by Dim Coumou, Jascha Lehmann, and Johanna Beckmann, “The weakening summer circulation in the Northern Hemisphere mid-latitudes” that argued:

Rapid warming in the Arctic could influence mid-latitude circulation by reducing the poleward temperature gradient. The largest changes are generally expected in autumn or winter but whether significant changes have occurred is debated. Here we report significant weakening of summer circulation detected in three key dynamical quantities: (i) the zonal-mean zonal wind, (ii) the eddy kinetic energy (EKE) and (iii) the amplitude of fast-moving Rossby waves. Weakening of the zonal wind is explained by a reduction in poleward temperature gradient. Changes in Rossby waves and EKE are consistent with regression analyses of climate model projections and changes over the seasonal cycle. Monthly heat extremes are associated with low EKE and thus the observed weakening might have contributed to more persistent heat waves in recent summers.

Coumou notes that “when the great air streams in the sky above us get disturbed by climate change, this can have severe effects on the ground. While you might expect reduced storm activity to be something good, it turns out that this reduction leads to a greater persistence of weather systems in the Northern hemisphere mid-latitudes. In summer, storms transport moist and cool air from the oceans to the continents bringing relief after periods of oppressive heat. Slack periods, in contrast, make warm weather conditions endure, resulting in the buildup of heat and drought.” Co-author Jascha Lehmann adds, “Unabated climate change will probably further weaken summer circulation patterns which could thus aggravate the risk of heat waves. Remarkably, climate simulations for the next decades, the CMIP5, show the same link that we found in observations. So the warm temperature extremes we’ve experienced in recent years might be just a beginning.”

These seem to be conflicting views.

So, how do the scientists who have published the recent paper that stands in stark contrast with these other recent findings explain the difference? I asked lead author Tapio Schneider to comment.

He told me that yes, there is a tension between the other work (the Comou et al paper) and his work, but there is also overlap and similarity. “Coumou et al. state that amplified warming of the Arctic should lead to reduced zonal jet speeds at fixed levels in the troposphere. This is an uncontroversial and well known consequence of thermal wind balance. Then they say that the reduced zonal jet speeds may lead to reductions in eddy kinetic energy (EKE), which is a measure of Rossby wave amplitude. That this can happen is likewise well documented. What affects eddy kinetic energies is a quantity known as the mean available potential energy (MAPE), which depends on temperature gradients (which also affect jet speeds) and other quantities, such as the vertical temperature stratification. Coumou et al. focus only on one factor influencing the EKE, the temperature gradient.”

The tension, he told me, is in what the other researchers (Coumou et al) draw from their results. “They show that warm summer months usually are associated with low EKE in the current climate, consistent with common knowledge: unusually warm conditions are associated with relatively stagnant air. They use this correlation in the current climate to suggest that reduced EKE in a future climate may also imply more (monthly) heat waves. While intuitive, this is not necessarily so. They say their suggestion is not in contradiction with our results because we considered temperature variability on shorter timescales (up to about two weeks), while their suggestion for more heat waves is made for monthly timescales. However, why the longer timescales should behave so differently is not made clear. “

As an onlooker, I take the following from this. First, there may be differences in time (and maybe space) scales of the analyses that might make them less comparable than ideal. Second, Schneider and Bischoff seem to be emphasizing synoptic cold outbreaks specifically. Schneider told me that they did look at temperature variability over longer time scales, but that did not make it into the paper. He said, “Even on monthly timescales, midlatitude temperature variance generally decreases as the climate warms, with a few regional exceptions (e.g., over Europe).”

Also, note that Schneider, Bischoff and Plotka, in this paper, do not address the specific problem of stationary Rossby waves, which probably has more to do with rainfall (lacking or heavy) than temperature, but is an important part of current changes in weather.

There has been some additional criticism of Schneider’s work on social media, etc. and perhaps the most significant one is this: Schneider, Bischoff and Plotka may have oversimplified the conditions in at least one of their models by leaving out continents. Also, Schneider et al has been picked up by a few of the usual suspects as saying that climate change will result in milder winters or less severe storms. This is not actually what the paper says. When people think “milder winter” they usually mean fewer severe storms, but various lines of evidence suggest that the notheastern US will experience more storms. For, example, see “Changes in U.S. East Coast Cyclone Dynamics with Climate Change” and “Global Warming Changing Weather in the US Northeast.”

UPDATE: I’ve received a comment from Dim Coumou pertaining to the differences between Schneider Et Al and Comou Et Al:

I see mostly overlap between the two studies, whereby ours really is an observational study analyzing data over the last 35 years (focusing on summers), and theirs is a theoretical and modeling study (focusing on winters). Interestingly both studies report similar dynamical changes but indeed come to somewhat different conclusions as to what this means for surface weather extremes.

We show that circulation (and notably EKE) has weakened in summer, that this has made weather more persistent and therefore favored the occurrence of prolonged heat waves in recent years. (We´re really focusing on present day climate and only show future projections for comparison with observations). As also discussed in our paper a drop in EKE leads to a reduction in weather variability on short timescales (less than a week) so this is consistent with the findings by Schneider et al. So indeed the issue of timescales is very important, and in my opinion prolonged extremes lasting several weeks are more important from an impact point of view.

Schneider, Bischoff and Plotka are well respected scientists and they are using methods that are generally accepted within climate science, yet have come to a conclusion different from what some of their colleagues have proposed. This is, in my opinion, a very good thing, and, certainly, interesting. I would worry if every climate scientist came up with the same result every time they tried something slightly different. The patterning (or changes in patterning) of air and sea currents under global warming has been the subject of a great deal of recent research, and there is strong evidence that changes are happening (such as in sea currents in the North Atlantic, and the jet stream effects discussed here) that have not been directly observed before. Because of the high level of internal (natural) variability, climate science works best when chunks of time 20 or 30 years long are considered. If we are seeing changes now that have really started to take off only five or ten years ago, and that are still dynamically reorganizing, how can the more ponderous, long term and large scale, thinking of climate science adjust and address those rapid changes? Well, we are seeing that process now in the climate change literature, and this paper is one example of it. I look forward to an honest, fair, and vigorous discussion in the peer reviewed literature.


Caption for the figure at the top of the post: FIG. 6. CMIP5 multimodel median values of 850-hPa potential temperature statistics for (left) DJF and (right) JJA. (a) Synoptic potential temperature variance u02 for the years 1980–99 of the historical simulations. (b) Per- centage change of the synoptic potential temperature variance u02 in the years 2080–99 of the RCP8.5 simulations relative to the years 1980–99 of the historical simulations shown in (a). (c) Percentage change of the squared meridional potential temperature gradient (›yu)2 in the years 2080–99 of the RCP8.5 simulations relative to the years 1980–99 of the historical simulations. (To calculate the gradients, mean potential temperatures were smoothed with a spherical harmonics filter that damped spherical wavenumbers greater than 6 and completely fil- tered out wavenumbers greater than 10.) (d) Percentage change of the squared mixing length L0 2 5 u0 2 /(›y u)2 implied by the variance and meridional potential temperature gradient, in the years 2080–99 of the RCP8.5 simulations relative to the years 1980–99 of the historical simulations. Synoptic potential temperature variations are bandpass filtered to 3–15 days. In the dark gray regions, topography extends above the mean 850-hPa isobar. The light gray bar blocks out the equatorial region, where potential temperature gradients are weak and their percentage changes become large.

How Sea Floor Ecosystems Are Damaged By, And Recover From, Abrupt Climate Change

A new study by Sarah Moffitt, Tessa Hill, Peter Roopnarine, and James Kennett (Response of seafloor ecosystems to abrubt global climate change) gets a handle on the effects of relatively rapid warming and associated Oxygen loss in the sea on invertebrate communities. The study looked at a recent warming event (the end of the last glacial) in order to understand the present warming event, which is the result of human-caused greenhouse gas pollution.

Here is what is unique about the study. A 30 foot deep core representing the time period from 3,400 to 16,100 year ago, was raised from a site in the pacific, and the researchers tried to identify and characterize all of the complex invertebrate remains in the core. That is not usually how it is done. Typically a limited number of species, and usually microscopic surface invertebrates (Foraminifera) only, are identified and counted. There are good reasons it is done that way. But the new study looks instead at non-single-celled invertebrates (i.e., clams and such) typically found at the bottom, not top, of the water column. This study identified over 5,400 fossils and trace fossils from Mollusca, Echinodermata, Arthropoda, and Annelida (clams, worms, etc.).

Complex invertebrates are important because of their high degree of connectivity in an ecosystem. In the sea, a clam, crab, or sea cucumber may be the canary in the proverbial coal mine. Study co-author Peter Roopnarine says, “The complexity and diversity of a community depends on how much energy is available. To truly understand the health of an ecosystem and the food webs within, we have to look at the simple and small as well as the complex. In this case, marine invertebrates give us a better understanding of the health of ecosystems as a whole.”

The most important finding of the study is this: the marine ecosystem sampled by this core underwent dramatic changes, including local extinctions, and took up to something like 1,000 years to recover from that. The amount of change in bottom ecosystems under these conditions was previously not well known, and the recovery rate was previously assumed to be much shorter, on the order of a century.

From the abstract of the paper:

Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans … in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record … demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mL·L?1 [O2]) associated with abrupt (<100 y) warming of the eastern Pacific. The biotic turnover and recovery events within the record expand known rates of marine biological recovery by an order of magnitude, from <100 to >1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems.

Lead author Sarah Moffitt, of the UC Davis Bodega Marine Laboratory and Coastal and Marine Sciences Institute notes, “In this study, we used the past to forecast the future. Tracing changes in marine biodiversity during historical episodes of warming and cooling tells us what might happen in years to come. We don’t want to hear that ecosystems need thousands of years to recover from disruption, but it’s critical that we understand the global need to combat modern climate impacts.”

There is a video:


Caption from the figure at the top of the post: Fig. 1. Core MV0811–15JC’s (SBB; 418 m water depth; 9.2 m core length; 34.37°N, 120.13°W) oxygen isotopic, foraminiferal, and metazoan deglacial record of the latest Quaternary. Timescale (ka) is in thousands of years before present, and major climatic events include the Last Glacial Maximum (LGM), the Bølling and Allerød (B/A), the Younger Dryas (YD), and the Holocene. (A) GISP2 ice core ?18O values (46). (B) Planktonic Foraminifera Globigerina bulloides ?18O values for core MV0811–15JC, which reflects both deglacial temperature changes in Eastern Pacific surface waters and changes in global ice volume. (C) Benthic foraminiferal density (individuals/cm3). (D) Relative frequency (%) of benthic Foraminifera with faunal oxygen-tolerance categories including oxic–mildly hypoxic (>1.5 mL·L?1 O2; N. labradorica, Quinqueloculina spp., Pyrgo spp.), intermediate hypoxia (1.5–0.5 mL·L?1 O2; Epistominella spp., Bolivina spp., Uvigerina spp.), and severe hypoxia (<0.5 mL·L?1 O2; N. stella, B. tumida) (19). (E) Log mollusc density (individuals/cm3). (F) Ophiuroids (brittle star) presence (presence = 1, absence = 0, 5-cm moving average). (G) Ostracod valve density (circles, valves/cm3) and 5-cm moving average.

Pine Beetle-Caused Forest Death, And Climate Change

There is some interesting new work carried out by researchers at Dartmouth College and the USDA Forest Service on the relationship between the Mountain Pine Beetle, major die-offs of forests in North America, and climate change.

The Mountain Pine Beetle (Dendroctonus ponderosae) is a kind of “bark beetle” (they don’t bark, they live in bark) native to western North America. They inhabit a very wide range of habitats and are found from British Columbia all the way south to Mexico. In British Columbia alone, the pine beetle, though a fairly complex process, has managed to destroy 16 of 55 million acres of forest. This epidemic of tree death is seen in mountain forest regions all across the western United States. The beetles affect a number of species of pine trees.

The beetle lays its eggs under the pine tree bark, and in so doing, introduces a fungus that penetrates adjoining wood. This fungus has the effect of suppressing the the tree’s response to the Pine Beetle’s larvae, which proceed to eat part of the tree. This suppressive effect blocks water and nutrient transport, together with the larvae eating part of the tree, quickly kills the host tree. The process can take just a few weeks. It takes longer for the tree to actually look dead (note the evergreen tree you cut and put in your living room for Christmas is dead the whole time it is looking nice and green and cheery). By the time the tree looks dead, i.e., the needles turn brown and fall off, it has been a dead-tree-standing for months and the Pine Beetles have moved on to find other victims.

It has long been thought that climate change has contributed to the western epidemic of Pine Beetles, as well as a similar epidemic in the Southeastern US (different species of beetles). The primary mechanism would be increasing winter extreme low temperatures. The very low temperatures would kill off the larvae, removing the threat of the beetle’s spread locally after that winter. Extreme winter temperatures have warmed by around 4 degrees C since 1960 across much of the beetle’s range. The lack of killing colds itself does not cause a beetle epidemic, but simply allows it, or produces a “demographic release.” If the beetles are already there, they have the opportunity to spread.

A recent study, just out, (see reference below) confirms this basic model but also adds a considerable degree of complexity. The study shows that there is not as strong of a correlation between raising winter temperatures above typical killing levels and the spread of the beetle. The study indicates that demographic release form an increase in extreme winter lows is part of the equation, but the situation is more complex and likely warming in general enhances beetle spread and reproduction during the summer part of its lifecycle, and may weaken the trees to make them more vulnerable to attack. In addition, other non-climate related factors probably play a role.

The study looked at several regions and assembled data on beetle frequency and spread over time, and various climate related data. From the abstract:

We used climate data to analyze the history of minimum air temperatures and reconstruct physio- logical effects of cold on D. ponderosae. We evaluated relations between winter temperatures and beetle abundance using aerial detection survey data… At the broadest scale, D. ponderosae population dynamics between 1997 and 2010 were unrelated to variation in minimum temperatures, but relations between cold and D. ponderosae dynamics varied among regions. In the 11 coldest ecoregions, lethal winter temperatures have become less frequent since the 1980s and beetle-caused tree mortality increased—consistent with the climatic release hypothesis. However, in the 12 warmer regions, recent epidemics cannot be attributed to warming winters because earlier winters were not cold enough to kill D. ponderosae…There has been pronounced warming of winter temperatures throughout the western US, and this has reduced previous constraints on D. ponderosae abundance in some regions. However, other considerations are necessary to understand the broad extent of recent D. ponderosae epidemics in the western US.

“This amount of warming could be the difference between pests surviving in areas that were historically unfavorable and could permit more severe and prolonged pest outbreaks in regions where historical outbreaks were halted by more frequent cold bouts,” says first author Aaron Weed, an ecologist at the National Park Service.

In the 11 coldest regions, winter temperatures cold enough to e lethal to D. ponderosae have become less frequent since the 1980s, and this is associated with an increase in tree mortality, confirming the link between warming conditions and increased parasite caused tree death. However, in the 12 regions with the warmest climate, recent epidemics are not clearly linked to warming winters simply because the earlier, colder, winters were already not cold enough to repress the tree-killing mountain pine beetle. This suggests that other factors may play a role in the epidemics in the western United States.

Evens so, the pattern of warming (including increase of minimum winter temperature) correlates to the demographic release of the mountain pine beetle. The authors note that “warming year-round temperatures that influence generation time and adult emergence synchrony … and drought effects that can weaken tree defenses …” are plausible explanations, but further note that a simple single explanation is not likely to be sufficient to explain the overall phenomenon. The link between warmer years, added number of generations per year, and the epidemic is explored here.

This is, in a sense, a numbers game. A cold winter does not kill off all of the beetles. However, no matter how cold the winter is, no beetles will be wiped out if they are not there to begin with. So, demographic release, which makes possible but does not cause an outbreak, could cause an abundance of beetles across a much larger area where, no matter what natural suppression may occur, they will then become more abundant over time.

As noted, the trees themselves matter. We can safely assume that generally changes in overall climate will mean that plant communities adapted to a given region might lose that adaptive edge and be subject to a number of problems which can then be exploited by a potentially spreading parasite. These changes in viability of plant communities are not all climate change related. Forest management, disturbance, and regional demographics (as forests age, they tend to change what they do) are also factors in this complex set of ecological relationships.

The bottom line. This study confirms the effects of warming, especially the increase of winter low temperatures, on the potential for D. ponderosae to spread rapidly locally and regionally. The study also calls into question the simplistic model that this is all that happens to explain the widespread epidemic of this beetle. Other factors, including other aspects of global warming, also contribute to the epidemics. In addition, and importantly, the study demonstrates a high degree of variability in the outcome of ecological and climate change.

This epidemic is probably the largest observed kill-off of forests caused by a parasite. So far it is much more severe in its effects than forest fires, but over the long to medium term, we will probably see increased frequency and severity of forest fires because of the abundance of fuel provided by the die-off.

Soucre:
Weed, A. S., Bentz, B. J., Ayres, M. P., & Holmes, T. P. (2015). Geographically variable response of Dendroctonus ponderosae to winter warming in the western United States. Landscape Ecology. doi:10.1007/s10980–015–0170-z

Text for the image at the top of the post, from the USDA:

The Mountain Pine Beetle is at epidemic levels throughout the western United States, including here in the Rocky Mountain Region … Forests affected here include several in Colorado, Wyoming, South Dakota and Nebraska. In northern Colorado and southeastern Wyoming, Mountain Pine Beetles have impacted more than 4 million acres since the first signs of outbreak in 1996. The majority of outbreaks have occurred in three forests: Arapaho-Roosevelt, White River and Medicine Bow/Routt.

Boston Snow Storms and Climate Change

From the Yale Climate Connections, a brief interview with Michael Mann.

Global warming can cause record winter storms. It may sound counterintuitive, but it’s no snow job. When the oceans warm, more water evaporates into the air.

MANN: “And what that means is there’s more precipitation. Water is cycling more vigorously through the atmosphere, and that gives us more extreme weather.”

That’s Michael Mann, a professor of meteorology at Penn State University. He says in summer, an unusually warm ocean can strengthen storms like Hurricane Irene.. but in winter, the evaporation from a warm ocean collides with cold arctic air and turns to snow.

As seawater evaporates, it also releases additional energy into the atmosphere. This extra energy then fuels storms, making them more intense.
This past winter, a large area of the North Atlantic was much warmer than usual — which Mann says contributed to the record Nor’easters that buried parts of New England in snow.

MANN: “So climate change is actually providing more energy to intensify these nor’easters, and it’s providing more moisture so that they can convert that moisture into record snowfalls.”

2014 was the warmest year on record for the global ocean surface. So New England, get your shovels ready for more extreme snow in coming years.

Hear the Interview Here

Should the Smithsonian and Other Museums Blow Off Big Fossil?

Let me start off by saying something you may not know. The big corporations and the 1%ers you have learned to hate fund many of the projects you’ve learned to love. I have not checked lately, but Murdoch and FOX corporation for several years in a row funded at a 50% or 60% level virtually all of the National Geographic specials produced. Major museums known for their great exhibits are often funded by the very corporations or individuals that the people who love those exhibits are (often justifiably) suspicious of. The great importance of private corporate or individual funding is also a factor for art museums, cultural entities like the Opera or Symphony, and of course, sports teams.

This is also true of educational institutions. You see this most obviously at schools of business or management. Say you want to visit the Carlson School of Management at the University of Minnesota. It is named after Curtis Carlson, who was Chair of the Carlson Companies (Radisson). Curt also owned TGI Fridays. You might park in the Toyota Parking lot. Perhaps you are going to a meeting at the Medtronic Dining Room followed by a lecture at the Honeywell Lecture Hall. Later, for entertainment you might catch a game at Target Field, or Target Center, or the Xcel Energy Center. Or perhaps you’ll visit the Opera or Symphony. While you are there, be sure to check out the Wall of Donors to see the numerous large companies (mostly Minnesota based) or wealthy individuals who make big donations there.

Well, OK, you probably already knew that large corporations and wealthy individuals are footing the bill for many of the trappings of our civilization, including educational enterprises, and ranging from academics to high culture to sports.

Lately there has been concern that the mix of large donors and missions of various institutions represents a conflict of interest, especially with regards to climate change and global warming.

We’ve seen the Harvard Smithsonian Center for Astrophysics as a conduit for moving money from Big Fossil (large corporations that depend, we presume, on the rejection of climate change science) to scientists who produce roundly criticized work used by climate change denialist in Congress (via the mechanism of Congressional testimony) to avoid implementing science-sound energy and environmental policies.

It has been argued that the David Koch human evolution exhibit at the Smithsonian inappropriately downplays the critical role of human caused climate change as a problem facing our species. The exhibit does mention future challenges, and a warming planet, but conveniently leaves off the anthropogenic part.

A couple of years back, the University of Minnesota bailed out of showing a documentary on the Mississippi River, which included quite a bit of material on pollution of the river caused by agriculture, allegedly because Big Ag interests pressured the administration. It has been suggested that was only one of several examples of The U bending to the agricultural industry.

Recently there has been a move to ask natural history museums to reduce or eliminate funding from Big Fossil, and to ask folks like the Kochs to not be on their boards of directors. This makes sense because of the potential conflict of interest, but it could also be a form of institutional suicide if the funding from those sources is both very important and irreplaceable.

How much of the science done by major academic institutions is influenced by funding? It makes sense, for example, for Big Ag to fund laboratories, graduate fellowships, and research at these institutions because they benefit from the training and research. But it might also make sense for Big Ag to influence what research is done, perhaps who gets the results, and most importantly perhaps, what research (or results) is NOT funded, or repressed. Same with Big Fossil. Same with Big Pharm. Same with Big Whatever.

And, of course, the same can be said of large museums. I can name one large museum (but I won’t) that totally avoids human evolution (but not necessarily evolution in general) because there are private donors who don’t think humans evolved. The aforementioned human evolution exhibit funded by Koch is probably a mild example of bias. I’ve seen a lot of human evolution exhibits, and so far the few that are quite willing to challenge visitors’ religious or other anti-science beliefs were entirely state funded, as far as I know.

I think it is appropriate to ask the Smithsonian to dump the Kochs and their ilk as donors and board members, because such stark request can form the core of an activist approach that could cause positive change. But I also think we need to recognize the difficult position these institutions are in. We need not only to tell them to change how they do things, but to suggest alternative approaches and facilitate those approaches. Big educational exhibits at museums should routinely be funded by public money, as many already are. Perhaps private donations should be funneled through third parties that are devoid of nefarious intentions and shady ties. One approach in the US might be to tie tax benefits to such a thing. You can get a tax benefit from donating to a museum to produce an exhibit, but you get a better tax benefit if you donate to the NSF or NIH museum exhibit and educational endowments, which are in turn distributed via the usual mechanism of carefully developed requests for proposals with peer review. That would let the Kochs have part of their cake and we (the citizens) get to eat the other part.

The way research, education, and public engagement is funded has become a problem. What do you think? How should we solve this problem?

Antarctic Ice Shelves Melting at Accelerating Rate

Antarctica is pretty much covered with glaciers. Glaciers are dynamic entities that, unless they are in full melt, tend to grow near their thickest parts (that’s why those are the thickest parts) and mush outwards towards the edges, where the liminal areas either melt (usually seasonally) in situ or drop off into the sea.

Antarctic’s glaciers are surrounded by a number of floating ice shelves. The ice shelves are really the distal reaches of the moving glaciers floating over the ocean. This is one of the places, probably the place at present, where melting accelerated by human caused greenhouse gas pollution occurs. The ice shelves are fixed in place along their margins (they typically cover linear fjord like valleys) and at a grounding point underneath the shelf some distance form the ice margin but under sea level.

The collapse or disintegration of an ice shelf is thought to lead to the more rapid movement of the corresponding glacial mass towards the sea, and increased melting. This is the big problem right now with estimating the rate of glacial melting in the Antarctic. This is not a steady and regular process, as rapid disintegration of an ice shelf is possible. Most likely, Antarctic glacial melting over the coming decades will involve occasional catastrophic of an ice shelf followed by more rapid glacial melting at that point.

Unfortunately, the ice shelves are generally becoming more vulnerable to this sort of process, a new study just out in Science shows. From the abstract:

The floating ice shelves surrounding the Antarctic Ice Sheet restrain the grounded ice-sheet flow. Thinning of an ice shelf reduces this effect, leading to an increase in ice discharge to the ocean. Using eighteen years of continuous satellite radar altimeter observations we have computed decadal-scale changes in ice-shelf thickness around the Antarctic continent. Overall, average ice-shelf volume change accelerated from negligible loss at 25 ± 64 km3 per year for 1994-2003 to rapid loss of 310 ± 74 km3 per year for 2003-2012. West Antarctic losses increased by 70% in the last decade, and earlier volume gain by East Antarctic ice shelves ceased. In the Amundsen and Bellingshausen regions, some ice shelves have lost up to 18% of their thickness in less than two decades.

This is one of many reasons that even the most extreme of the IPCC estimates of ice loss (generally) and its contribution to sea level rise have to be seen as a lower limit. This is a substantial change, and it is very recent. It isn’t just that the ice sheets have gotten thinner, but also, that the rate of melting at these margins is increasing.

Caption to figure: Fig. 1 Eighteen years of change in thickness and volume of Antarctic ice shelves.
Rates of thickness change (m/decade) are color-coded from -25 (thinning) to +10 (thickening). Circles represent percentage of thickness lost (red) or gained (blue) in 18 years. Only significant values at the 95% confidence level are plotted (see Table S1). Lower left corner shows time series and polynomial fit of average volume change (km3) from 1994 to 2012 for the West (in red) and East (in blue) Antarctic ice shelves. Black curve is polynomial fit for All Antarctic ice shelves. We divided Antarctica into eight regions (Fig. 3), which are labeled and delimited by line segments in black. Ice-shelf perimeters are shown as a thin black line. The central circle demarcates the area not surveyed by the satellites (south of 81.5°S). Original data were interpolated for mapping purposes (see Table S1 for percentage area surveyed of each ice shelf). Background is the Landsat Image Mosaic of Antarctica (LIMA).

Who Is Andreas Lubitz?

A few links to places addressing this important question:

Andreas Lubitz: 5 Fast Facts You Need to Know

Lubitz, 28, was a German national living in Montabaur, Germany. Montabaur lies in the famous Rhineland region of Germany, about halfway between Cologne and Frankfurt. The Telegraph reports he lived there with his parents and also had an apartment in Dusseldorf.

The FAA lists “Am Spiessweiher 8, Montabaur, Germany” as Lubitz’s address. Google Street View is not available for Lubitz’s home, but the Google Map below shows that he lived in a suburban area.

Who is Andreas Lubitz? Everything we know so far about Germanwings co-pilot

Full name: Andreas Guenter Lubitz.

Who was Andreas Lubitz? Germanwings co-pilot who ‘intentionally killed’ 150 passengers in deliberate Alps crash

German media reports he had 630 flight hours and joined budget airline Germanwings straight out of Lufthansa Flight Training School in Bremen in September 2013. Authorities have not confirmed if he had any experience as a professional pilot prior to that.

Andreas Lubitz: Who is Germanwings co-pilot who ‘locked out captain and crashed flight 9525 into French Alps’?

Lubitz is that the 28-year-old was from Montabaur, a town in the district seat of the Westerwaldkreis in Rhineland-Palatinate, Germany.

The LSC club, where he was a member, posted a death notice on their website naming him.

Andreas Lubitz a young co-pilot loved flying, no terrorist links

Lubitz scored 100 per cent in his psychological testing to become a professional pilot, Carsten Spohr, an official with the Germanwings parent company Lufthansa said on Thursday.
“There wasn’t the least doubt in his capability,” Spohr said at at press conference.
Lubitz started his training in 2008, which was interrupted for several months for an unspecified reason, Spohr said.
“I can’t say more about the reasons for his absence,” Lubitz said.

Science Museums: Cut Ties to Big Carbon, Kick Out The Kochs!

There is a letter signed by top scientists demanding that science museums cut all their ties to Big Fossil, and where appropriate, kick the Koch Brothers off their boards.

The letter says, in part,

As members of the scientific community we devote our lives to understanding the world, and sharing this understanding with the public. We are deeply concerned by the links between museums of science and natural history with those who profit from fossil fuels or fund lobby groups that misrepresent climate science.

Museums are trusted sources of scientific information, some of our most important resources for educating children and shaping public understanding.

We are concerned that the integrity of these institutions is compromised by association with special interests who obfuscate climate science, fight environmental regulation, oppose clean energy legislation, and seek to ease limits on industrial pollution.

You can read the entire letter and see the signers here.

For example, Big Fossilman David Koch is a major donor to the Smithsonian and sits on its board Board. That’s the same Smithsonian who harbors science denialist Willie Soon and at least one other denier.

“It is one thing for David Koch to give money to Lincoln Center or Carnegie Hall, but it is quite another to support a science/natural history museum that has a role to play in doing research on, and helping educate the public about, climate change, the greatest threat ever to confront humanity”, said signer and Nobel laureate Eric Chivian. “The philanthropy serves to silence any criticism of the practices of the donor, and even, possibly, any critical discussion of the issue.”

“Energy companies and the Koch brothers gain social license from their association with these scientific institutions. It gives them cultural capital and credibility as supporters of science, yet they fund scientists and lobby groups that spread climate science disinformation and block action on climate change.” says Beka Economopoulos, director of The Natural History Museum, which organized the letter.

Climate scientist Michael Mann, who also signed, noted that “corporate polluters are embedding themselves in these spaces that communicate science to the public. Cloaked in the garb of civic-mindedness, they launder their image while simultaneously and covertly influencing the content offered by those institutions. It’s a public relations move of the highest order. David Koch sits on the board of our nation’s largest and most respected natural history museums, while he bankrolls groups that deny climate science. There is a clear contradiction between the mission of these museums and the politics of their patron.”

There is a petition that goes along with the letter that you might want to sign. It is HERE.

LOL Patrick Moore

You probably already know that Patrick Moore is a guy who was involved early on in Greenpeace, and has since used his Greenpeace connection (claiming to have been a founder, though he wasn’t) to get paid speaking gigs all around the world. He speaks out in favor of nuclear energy (much to the annoyance of Greenpeace) and he is a global warming denier.

Anyway, here is a very funny interview with Moore that is supposed to be about GMOs but turns out to be about … well, just watch:

Hat Tip GM Watch

Meanwhile, don’t forget to listen to my interview with Anastasia Bodnar on GMOs.

GMOs Are Interesting

The podcast for my interview with Anastasia Bodnar is now available HERE. There are also a couple of links there that you might find of interest.

We focuses on the actual process and science of GMOs and spent very little time on the usual issues. I hope many of you find the interview different and refreshing. Total change of pace from the usual yammering, or at least, that was my intent. Also, for those of you who heard the first interview, I assure you, this time the sound quality is excellent!

Enjoy.

How do bird species compete with each other?

This is one of those great examples of research you can probably use in an advanced biology classroom (high school) or intro college bio pretty effectively. It includes birds. It includes hormones. It includes evolution. What else is there, really?

I did a very brief writeup on it here, and you can get the original paper which is very straight forward and readable.

The bottom line: Females in one species of bird manage to figure out that under certain, occasional conditions if they produce really obnoxious and overbearing sons, those sons will do well. So they do. There is a phylogenetic reasons they can do this, and it has to do with development and adaptive change. In other words, this example is a Tinbergian wet dream.

Check it out.

Drought in California and Climate Change: They are linked

A paper just out now in PNAS by Noah Diffenbaugh, Daniel Swain, and Danielle Touma shows that “Anthropogenic warming has increased drought risk in California.” From the abstract:

… We find that although there has not been a substantial change in the probability of either negative or moderately negative precipitation anomalies in recent decades, the occurrence of drought years has been greater in the past two decades than in the preceding century. In addition, the probability that precipitation deficits co-occur with warm conditions and the probability that precipitation deficits produce drought have both increased. Climate model experiments with and without anthropogenic forcings reveal that human activities have increased the probability that dry precipitation years are also warm. Further, a large ensemble of climate model realizations reveals that additional global warming over the next few decades is very likely to create ?100% probability that any annual-scale dry period is also extremely warm. We therefore conclude that anthropogenic warming is increasing the probability of co-occurring warm–dry conditions like those that have created the acute human and ecosystem impacts associated with the “exceptional” 2012–2014 drought in California.

Michael Mann and Peter Gleick have written a commentary for PNAS to accompany that research. The graphic at the top of the post is from that study. They note:

California is experiencing extreme drought. Measured both by precipitation and by run- off in the Sacramento and San Joaquin river basins, 10 of the past 14 y have been below normal, and the past 3 y have been the driest and hottest in the full instrumental record. A plot of temperature and precipitation anom- alies over the full instrumental record from 1895 through November 2014 shows that the 3-y period ending in 2014 was by far the hottest and driest on record (Fig. 1). As of the publication of this commentary, the state appears headed into a fourth consec- utive year of water shortfall, leading to massive groundwater overdraft, cutbacks to farmers, reductions in hydroelectricity gen- eration, and a range of voluntary and man- datory urban water restrictions.

A number of studies have examined the California drought to try to determine if it was “caused by” (or otherwise affected by) human greenhouse gas pollution. These studies vary in their level of attribution, but increasingly it is becoming clear that anthropogenic global warming has a very big hand in this.

Mann and Gleick tackle the problem of defining drought. There are multiple ways to do so, and they relate to different causes. The plethora of definitions and relevant variables allows for a given study to miss any global warming effect by picking certain factors and ignoring others. Studies that look mainly at inputs to the hydrological system (i.e., rainfall) tend to miss the output part of the equation, including evaporation, which is exacerbated by a warming climate. Mann and Gleick point out that the Diffenbaugh study adds significant weight to the idea that anthropogenic climate change has increased the frequency, magnitude, and duration of California’s droughts. Perhaps more importantly, the Diffenbaugh study suggests “the emergence of a climatic regime in which all future dry years coincide with warmer conditions.”

Gleick told me, “The scientific evidence showing the growing influence of climate changes on extreme events around the world, including the ongoing California drought, continues to pile up. The clearest piece of this is the record high, and increasing, temperatures, which directly influence the availability and demand for water, but there is also growing evidence that climate change is influencing pressure dynamics and atmospheric circulation patterns that either bring, or divert, water from the west coast of the United States.”

So, the current drought in California is linked to human induced climate change, and in the future, this will be a more common phenomenon than it has in the base, according to the best available science. But what about other effects of climate change? I asked Michael Mann about the relationship between California Drought and his recent study showing that we should soon be entering a period (over the next couple of decades) during which heat that has been hiding in the oceans will be leaving it’s watery milieu and joining us up here on the surface. He told me, “Here is the linkage I think is most relevant: the “faux pause”, in our recent study, was closely tied to the predominance of La Nina-like conditions in the tropical Pacific for a large part of the past decade, and these same conditions are closely linked with California drought (La Nina years tend to be drought years in California, while El Nino years tend to be wet years—though this doesn’t necessarily hold true for every single event). So one might imagine that a return to a greater tendency for El Nino-like conditions in the tropical Pacific over the next decade or two (which would spell an end to the “Faux Pause”) could actually be a mitigating effect as far as California drought is concerned. A bit counter-intuitive, but that’s best assessment here.”

New Research Shows Exceptional Slowdown In Major Atlantic Ocean Currents (UPDATED)

Climate scientists have noticed a disturbing pattern in the North Atlantic. This is the relative cooling of surface waters in the area fed by the Gulf Stream. This pattern has emerged over recent decades, and may portend very rapid and potentially disruptive climate change in the upcoming decades. The cooling is not subtle at all, and looks like this:

Map based on NASA GISS data of warming 1901-2013
Map based on NASA GISS data of warming 1901-2013

So what does this mean? A paper out just today describes, explains, and discusses this odd anomaly and its potential consequences. First, a bit of context.

The Earth’s climate follows certain patterns. Most obviously it is warmer at the equator, colder at the poles. Less obvious if you’ve not looked into this is the presence of a very wet band around the middle of the earth, flanked to the north and south by irregular dry bands (that’s where most of the deserts are), with these flanked by the temperate zone, where you have more moisture and highly seasonal temperatures, and so on.

This pattern emerges as a complex response to two major inputs. First the Earth is spinning, and second, the Earth is heated more at the equator than the poles, so heat must move through air and water currents towards the north and south.

One of the major systems that moves heat away from the equator is known sometimes as the Atlantic Conveyor, which is really part of a lager system of sea currents that includes the Gulf Stream. Notice that the Indian Ocean is sequestered mostly in the Southern Hemisphere, bordered along the west by Africa and the north by Asia. Extra warm water in the Indian ocean tends to make its way around the southern tip of Africa, and up the Atlantic, which is a round about route. This water eventually makes its way to the North Atlantic, where it cools, and owing to evaporation, becomes extra salty. This drives the formerly warm surface water into the depth of the ocean, where it flows along the bottom of the Atlantic south, eventually returning (I oversimplify a bit) to the Indian Ocean and elsewhere.

This system is also known as the AMOC (Atlantic Meridional Overturning Circulation) and is part of the global “Thermohaline Circulation” system.

Meanwhile, a smaller but similar aspect of this system starts with the Gulf of Mexico. This water becomes quite warm from the Sun, but is blocked from moving directly north by the presence of North America, with Florida adding to the captive nature of those waters. But the water does make its way around Florida and flows north along the East coast of the US, and eventually also reaches the North Atlantic, and similarly, contributes to the saline deep currents.

Because salinity partly, even largely, drives this system, adding fresh water to the North Atlantic may interfere with this system of currents. How do you get enough fresh water to do this? In the past, huge volumes of fresh water probably entered the North Atlantic every now and then as large outflows of giant inland lakes, formed by melting glaciers, broke through barriers of ice or sediment. There is some evidence that in the past this sort of thing may have partly, or even completely, shut down the Atlantic Conveyor system, which would have had huge impacts on climate.

Today there seems to be two main sources of extra fresh water in the area. One is during years (or decades) when there is a larger than usual number of ice bergs floating into the North Atlantic from the Arctic. The other, potentially, is from melting of Greenland’s fast glaciers, a process that has recently speeded up because of human caused greenhouse gas pollution warming the Earth.

By now you may recognize this scenario as the basis for the Hollywood disaster movie “The Day After Tomorrow.” In that movie the thermohaline circulation system shut down and an ice age instantly gripped the planet. Giant frozen tornadoes came plummeting down from the Stratosphere. One of them hit the helicopter the British Royal Family was escaping in. Everybody in the US ended up in Mexico.

Every one who survived, that is.

The thing is, now, this can’t happen. Well, that particular scenario can’t ever really happen. But yes, the shutting down of this system can theoretically cause the onset of an ice age, or at least a mini-ice age, and has done so in the past. But no, it can’t now because our planet has warmed too much from human greenhouse gas pollution to allow that to happen. That may be the one good thing about global warming.

The new research does suggest, though, that this major pattern of circulation appears to be slowing down. This will have a number of effects. It will likely change the weather in Europe a bit. It will likely cause an increase in sea level along the US East Coast, because the current (and former) system piles up water towards the east and lowers it in the west, within the North Atlantic. That could be worth a few inches.

According to lead author Stefan Rahmstorf, “It is conspicuous that one specific area in the North Atlantic has been cooling in the past hundred years while the rest of the world heats up. Now we have detected strong evidence that the global conveyor has indeed been weakening in the past hundred years, particularly since 1970,” says Rahmstorf. If the slowdown of the Atlantic overturning continues, the impacts might be substantial. Disturbing the circulation will likely have a negative effect on the ocean ecosystem, and thereby fisheries and the associated livelihoods of many people in coastal areas. A slowdown also adds to the regional sea-level rise affecting cities like New York and Boston. Finally, temperature changes in that region can also influence weather systems on both sides of the Atlantic, in North America as well as Europe.”

The researchers used a combination of sea surface, atmospheric, and proxy (mainly coral) indicators of temperature to indirectly measure changes in ocean currents over time.

According to climate scientist Jason Box, “Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation. So the human-caused mass loss of the Greenland ice sheet appears to be slowing down the Atlantic overturning – and this effect might increase if temperatures are allowed to rise further.” Michael Mann, another author of the paper, adds, “Common climate models are underestimating the change we’re facing, either because the Atlantic overturning is too stable in the models or because they don’t properly account for Greenland ice sheet melt, or both. That is another example where observations suggest that climate model predictions are in some respects still overly conservative when it comes to the pace at which certain aspects of climate change are proceeding.”

What happens if the system actually turns off completely? It was formerly thought that the chances of this happening were small, but this research, conforming to a growing body of expert opinion, suggest that the chances of that may be higher than previously thought. Were this to happen the main characteristic of any effects would be rapidity. Whatever happens would happen fast, and rapidly changing climate is generally regarded as bad no matter what the change itself really is.

UPDATE ADDED:

A criticism of this work has emerged, suggesting that another study indicates that there is no a long-term slowdown of the Atlantic Meridional Overturning Circulation (as suggested by the research covered here). That criticism is incorrect. Michael Mann, one of the AMOC study’s author has written a clarification on his facebook page. He begins:

Some critics have tried to make hay over a previous article from last year by URI Graduate School of Oceanography scientist Tom Rossby (see: http://www.gso.uri.edu/b…/rossby-gulf-stream-is-not-slowing/) they claim contradicts our recent Nature Climate Change study finding evidence for a long-term slowdown of the Atlantic Meridional Overturning Circulation (“AMOC”). …

Rossby employs direct measurement of Gulf Stream transport using a ship-board acoustic Doppler current profiler (ADCP) over the interval 1993-2012. I have no reason at all to doubt Rossby’s findings. And they do *not* conflict with our own findings (though some have misleadingly sought to assert they do) for two fundamental reasons:

Mann’s entire post is HERE and you should go read it.

Additional Resources:

The article:

Rahmstorf, S., Box, J., Feulner, G., Mann, M., Robinson, A., Rutherford, S., Schaffernicht, E. (2015): Evidence for an exceptional 20th-Century slowdown in Atlantic Ocean overturning. Nature Climate Change (online) [DOI: 10.1038/nclimate2554 ]

Stefan Rahmstorf, lead author, has this blog post at RealClimate: What’s going on in the North Atlantic?

Figure caption from the original article, goes with the graphic at the top of the post:

Figure 3. Surface temperature time series for different regions. Data from the proxy reconstructions of Mann et al.12,13, including estimated 2-? uncertainty bands, and from the HadCRUT4 instrumental data49. The latter are shown in darker colours and from 1922 onwards, as from this time on data from more than half of all subpolar-gyre grid cells exist in every month (except for a few months during World War II). The orange/red curves are averaged over the subpolar gyre, as indicated on Fig. 1. The grey/black curves are averaged over the Northern Hemisphere, offset by 3 K to avoid overlap. The blue curves in the bottom panel show our AMOC index, namely the difference between subpolar gyre and Northern Hemisphere temperature anomalies (that is, orange/red curves minus grey/black curves). Proxy and instrumental data are decadally smoothed.

A neat video of the thermohaline circulation system.

A movie produced by Peter Sinclair, that goes along with THIS blog post.

Coverage by Chris Mooney at the Washington Post: Global warming is now slowing down the circulation of the oceans — with potentially dire consequences


Other posts of interest:

    – [Important new meta-study of sea level rise in the US.](http://scienceblogs.com/gregladen/2014/09/05/important-new-meta-study-of-sea-level-rise-in-the-us/)
    – [Whatever you thought about sea level rise, it’s worse than you were thinking.](http://scienceblogs.com/gregladen/2013/12/05/whatever-you-thought-about-sea-level-rise-its-worse-than-you-were-thinking/)
    – [How high can the sea level rise if all the glacial ice melted?](http://scienceblogs.com/gregladen/2013/06/18/how-high-can-the-sea-level-rise-if-all-the-glacial-ice-melted/)
    – [Bangladesh and Sea Level Rise](http://scienceblogs.com/gregladen/2013/04/29/bangladesh-and-sea-level-rise/)

Also of interest: In Search of Sungudogo: A novel of adventure and mystery, set in the Congo.

Shut. Up. NOAA says February 2nd Warmest on Record

And by “Shut. Up.” I mean shut up about whether or not global warming is real.

The National Climatic Data Center of NOAA has just released the number representing the Earth’s surface temperature for February and it is a shocking 0.82 degrees C above the 20th century average. This is the second warmest Feb on record, and I’m pretty sure it is the third warmest month on record, in that data base.

Roughly speaking, the coldest we have experienced, the Last Glacial Maximum, was about 6 degrees colder than at present. It is generally thought that we need to keep the global surface temperature below about 2 degrees C above the preindustrial level. The 20th century average used by NOAA includes decades warmed considerably by human caused greenhouse gas pollution; the actual difference between the best estimate (BEST 1750-1850) of the pre-industrial temperature and the present is about 1.5 degrees C.

This high value is not surprising since the estimate of the Earth’s surface temperature from NASA GISS, which came out a few days ago, also places February very high in temerature.

March, by the way, has been pretty warm. We’ve had quite a trend of very warm months, and it appears to not be letting up.

For a comparative perspective, see also this.