Month: April 2018

Low Bering Sea ice mostly due to south winds, no data on an impact for polar bears

Sea ice in the Bering Sea this winter was said to be the lowest since the 1850s, largely driven by persistent winds from the south rather than the usual north winds although warm Pacific water was a factor early in the season (AIRC 2018). But what, if any, impact is this surprisingly low winter and spring ice cover likely to have on Chukchi Sea polar bear health and survival?

Rode and Regehr 2010_Chukchi_report2010_Fig1_triplets_labelled

In fact, research on Chukchi Sea polar bears has included so few examples of individuals utilizing the Bering Sea in winter (Jan-March) and early spring (April-May) that any conclusions regarding an impact from this year’s sea ice conditions are likely to be invalid. In short, we don’t know what will happen since it has not happened before within living memory; the opinions of polar bear specialists must be taken with a grain of salt because so many of their previous assumptions have turned out to be wrong (Crockford 2017a,b, 2018), see here, here, and here. Seals, walrus and polar bears are much more flexible and resilent to changes in habitat conditions than most modern biologists give them credit for and consequently, it will be fascinating to see how the ice will change over the coming months and how the animals will respond.

Sea ice extent 2018 March average NSIDC

map-ChukchiSeaA sampling map from Rode et al. 2014 (below) shows only a handful of bears were captured south of the Bering Strait, virtually all in the most recent period (2008-2011), as the map from Garner et al. 1990, further below, shows (only one bear south of the Bering Strait in 1987):

Rode et al. 2014 Chukchi Beaufort pbs Fig 1

Garner et al 1990 Chukchi and Bering sea PBs Fig 2

Data on polar bear movements in 1986-87 from Garner et al. (1990 Fig 3D Jan-March and Fig 3A April-May) further show only a few bears captured in the Chukchi Sea ventured south into the Bering Sea in winter and spring.

Garner et al. (1990) Fig 3D Jan-March:

Garner et al 1990 Chukchi and Bering sea PBs Fig 3D Jan-March

Garner et al. 1990 Fig 3A April-May:

Garner et al 1990 Chukchi and Bering sea PBs Fig 3A April May

This year, there was virtually no ice remaining in the Bering Sea at the end of April and this clearly represents unusual conditions. But it is not obviously catastrophic, since there is still a lot of ice in the Chukchi Sea for Chukchi Sea bears to hunting and mate upon:

Sea ice 2018 April 28 NSIDC

Most of the known impact of low Bering Sea ice this winter has been on humans: local hunters having to adjust their hunting schedules and polar bear specialists unable to land their helicopters safely on the ice.

Bering Sea walrus, seals, and polar bears move with the mobile pack ice and therefore any individuals that spent the winter in the Bering Sea this year (see map below) would have traveled with the ice north into the Chukchi Sea as the ice retreated earlier than usual.

Sea ice extent 2018 Feb average NSIDC

Just because virtually all Chukchi Sea bears (and many seals) will have been forced to stay within the Chukchi Sea itself for most of this winter and early spring does not necessarily mean a problem ahead. However, when people are looking for problems, that’s often all they see:

The same excellent conditions for ringed and bearded seals existed last summer (longer open water season, therefore more time for the seals to feed and fatten up for the winter) as existed since 2008 (Crawford et al. 2015; Crawford and Quakenbush 2013), so seal pups should be just as plentiful in the Chukchi Sea this spring as last spring (Rode et al. 2014, 2018). This will allow most Chukchi bears to put on enough fat to see them through an ice-free period as long as 4-5 months, just as bears in Western and Southern Hudson Bay have done for decades (Castro de la Guardia 2017; Obbard et al. 2016).

There is no reason to expect that well-fed Chukchi Sea bears will not be able to endure a similar fast (whether they are on the sea ice over the Arctic Basin or on land), since they have already been thriving with a fast of one month or longer in recent years (Rode et al. 2014, 2018). However, polar bear specialist Andrew Derocher thinks that even one month of ice-free conditions will mean the demise of some Chukchi Sea bears. While he’s technically correct — some bears starve every year (usually very young and old bears) no matter how good the ice conditions — but that’s not what he’s trying to say:

Sea ice cover is highly variable in the Bering Sea (Brown et al. 2011). In 2012 (when summer sea ice for the Arctic was at its lowest since satellite records began), spring ice in the Bering Sea was the highest it had been since 1979. Spring ice cover was very low in 1979 (when summer sea ice for the Arctic was very high), covering only 130,000 km2 at the end of May compared to 350,000 km2 in 2012.

In other words, sea ice cover for the Bering Sea in spring is not a portend for what the Arctic will experience at the height of summer and the reverse is also not true: Arctic ice cover in September is not a reflection of Bering Sea ice cover in spring.

As a consequence, we shall have to wait and see what the coming months bring. Sea ice retreat in the Chukchi may stall for months or continue to decline. It may indeed be a rough year for Chukchi Sea polar bears but after a decade or more of excellent conditions, the population can likely rebound from a single challenging spring with less than optimal ice cover. As far as I know, no one predicted this year’s low Bering Sea ice conditions, and there is no reason to expect it will be repeated next year or that this is a “new normal” for the region.


Arctic Research Center (IARC) 2018. Bering Strait: An overview of winter 2018 sea ice conditions. University of Alaska Fairbanks. pdf here.

Brown, Z.W., van Dijken, G.L. and Arrigo, K.R. 2011. A reassessment of primary production and environmental change in the Bering Sea. Journal of Geophysical Research 116:C08014. doi:10.1029/2010JC006766.

Castro de la Guardia, L., Myers, P.G., Derocher, A.E., Lunn, N.J., Terwisscha van Scheltinga, A.D. 2017. Sea ice cycle in western Hudson Bay, Canada, from a polar bear perspective. Marine Ecology Progress Series 564: 225–233.

Crawford, J. & Quakenbush, L. 2013. Ringed seals and climate change: early predictions versus recent observations in Alaska. Presentation by Justin Crawfort, 28th Lowell Wakefield Fisheries Symposium, March 26–29, Anchorage, AK. Available from [accessed June 7, 2013].

Crawford, J.A., Quakenbush, L.T. & Citta, J.J. 2015. A comparison of ringed and bearded seal diet, condition and productivity between historical (1975–1984) and recent (2003–2012) periods in the Alaskan Bering and Chukchi seas. Progress in Oceanography 136: 133-150.

Crockford, S. 2017a. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3

Crockford, S. 2017b. Twenty good reasons not to worry about polar bears, an update. Global Warming Policy Foundation Briefing Paper #28, London. See the pdf here

Crockford, S.J. 2018. State of the Polar Bear Report 2017. Global Warming Policy Foundation Report #29. London. pdf here.

Garner, G.W., Knick, S.T., and Douglas, D.C. 1990. Seasonal Movements of Adult Female Polar Bears in the Bering and Chukchi Seas. Bears: Their Biology and Management 8: 219-226.

Obbard, M.E., Cattet, M.R.I., Howe, E.J., Middel, K.R., Newton, E.J., Kolenosky, G.B., Abraham, K.F. and Greenwood, C.J. 2016. Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice. Arctic Science 2:15-32. DOI 10.1139/AS-2015-0027

Rode, K.D., Regehr, E.V., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W., and Budge, S. 2014 [in print]. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20(1):76-88. [updated February 9 2014]

Rode, K. and Regehr, E.V. 2010. Polar bear research in the Chukchi and Bering Seas: A synopsis of 2010 field work. Unpublished report to the US Fish and Wildlife Service, Department of the Interior, Anchorage. pdf here.

Rode, K.D., Wilson, R.R., Douglas, D.C., Muhlenbruch, V., Atwood, T.C., Regehr, E.V., Richardson, E.S., Pilfold, N.W., Derocher, A.E., Durner, G.M., Stirling, I., Amstrup, S.C., St. Martin, M., Pagano, A.M. and Simac, K. 2018b. Spring fasting behavior in a marine apex predator provides an index of ecosystem productivity. Global Change Biology.

via polarbearscience

April 30, 2018 at 10:34PM

Pielke on Climate #10

quote-the-white-house-is-a-bully-pulpit-theodore-roosevelt-67-54-41Welcome to issue #10 of my occasional newsletter on climate and energy issues. As a reminder, my day-to-day research or writing is focused on sports governance and various issues of science policy. But I’ve written a fair bit on the topics of climate and energy over the past 25 years, including two recent books and a boatload of academic papers, and I’m paying attention.

So caveat lector!

A few things to say up front:

  • If you appreciate the perspective, consider the tip jar to your right.
  • Thanks to those of you who have already contributed!
  • These funds continue to help me defray the costs of several trips where I have had the chance to develop and present new talks. I am unfunded on this topic.
  • Contributions are much appreciated.
  • If you don’t like what I write or don’t like me, then don’t read it – no big deal, I’m just a professor with a blog.
  • If you’d like to engage, consider a comment, Tweet @ me (@rogerpielkejr) or send an email. I am happy to discuss or debate. I’ve had great feedback on these newsletters.
  • Also, if you have a pointer or tip, please send that along as well. Anonymity guaranteed for those who want it.
  • Social media warning: if you choose to call me names or lie about me, oh-so-common in discussing climate, then you will be muted or ignored.

With that . . .

Talk on “Extreme Weather and Extreme Politics”

  • Earlier this month I gave a talk at the University of Minnesota.
  • It was my first public talk on climate since being “investigated” by Rep. Raul Grijalva (D-AZ) in 2015.
  • It is also the first and only invitation I’ve received to give a public talk on climate at a US university since 2015.
  • Before that I received about 2-3 invitations per month.
  • Delegitimization works.
  • You can see my slides from Minnesota at
  • Much of what I presented (and more) will appear in the 2nd edition of Disasters and Climate Change.
  • Below I document a key episode in my own experience that I have never looked back on in detail.
  • The timeline is of use to me, shared here for anyone else who might be interested.

A Look Back at the Holdren-Pielke Debate of 2014

  • One of the more bizarre experiences I’ve had in the climate debate was when President Obama’s science advisor, John Holdren, posted a weird, 6-page screed about me on the White House web site.
  • Here is a reconstruction of and look back at those events, and an evaluation how they look from vantage point of 2018.
  • This look back is mainly just for me, as when you are in the spin cycle it can be hard to see what has happened at the time.
  • The Holdren episode ultimately led to me being investigated by a member of Congress with a major impact on my life and career.
  • I’ve not taken a close look back at this episode, it’s time for me to document exactly what transpired. If you are not interested, this would be a good place to take the exit ramp.
  • In July 2013, I testified before the US Senate Environment and Public Works Committee on extreme events.
  • You can see my 5 minute statement below and read my full written testimony here in PDF. That testimony was widely discussed.
  • I followed that testimony up with similar testimony before the US House a few months later, in October 2013.
  • I wrote a blog post explaining that the science on these issues was solid. Even so I argued that “zombie science” (to the contrary) would always be with us.
  • On February 14, 2014, Holdren was quoted as saying: “We really understand a number of the reasons that global climate change is increasing the intensity and the frequency and the life of drought in drought-prone regions. This is one of the better-understood dimensions of the relationship between global climate change and extreme weather in particular regions. . . There are other, more subtle, ways climate change may be affecting the prevalence of drought; scientists are still arguing about those. The three I just described are more than enough to understand why we are seeing droughts in drought-prone regions becoming more frequent, more severe and longer.”
  • Two weeks later Dr. Holdren was asked about these statements by Senator Jeff Sessions before the Senate Environment and Public Works Committee, the same committee that I had testified before the previous July.
  • The full exchange between Sessions and Holdren can be found here, but below are the key excerpts.
  • After some sparring on what Dr. Holdren said or didn’t say a few week previous, Senator Sessions said:
    • “Well, let me tell you what Dr. Pilkey (sic) said, who sat in that chair you are sitting in today just a few  months ago, he is a climate impact expert, and he agrees that  warming is partly caused by human emissions. But he testified “It is misleading and just plain incorrect to claim that  disasters associated with hurricanes, tornadoes, floods or  droughts have increased on climate change time scales either in  the United States or globally.”
  • Holdren replied with a delegitmization effort, saying that I was
    • “not  representative of the mainstream scientific opinion on this  point. And again, I will be happy to submit for the record  recent articles from Nature, Nature GeoScience, Nature Climate  Change, Science and others showing that in drought-prone regions droughts are becoming more intense.”
  • Of course, Holdren was incorrect.
  • My views are 100% consistent with those of the IPCC, the very definition of “mainstream scientific opinion.”
  • Holdren promised to submit scientific evidence for the hearing record in support of his views, Sessions said he looked forward to it.
  • Three days later Holdren’s missive about me was posted on the White House website, titled Drought and Global Climate Change: An Analysis of Statements by Roger Pielke Jr ” (here in PDF).
  • Holdren singled out just 2 statements that I had made in my testimony:
    • “It is misleading, and just plain incorrect, to claim that disasters associated with hurricanes, tornadoes, floods or droughts have increased on climate timescales either in the United States or globally.”
    • Drought has “for the most part, become shorter, less, frequent, and cover a smaller portion of the U.S. over the last century”. Globally, “there has been little change in drought over the past 60 years.”
  • The quotes in blue above are from the US National Climate Assessment (former) and a Nature paper (latter) on global drought trends.
  • Holdren explained his objections:
    • “I replied that the indicated comments by Dr. Pielke … were not representative of mainstream views on this topic in the climate-science community; and I promised to provide for the record a more complete response with relevant scientific references. “
  • The slide below shows the entirety of my discussion of drought in my 2013 Senate testimony, which consisted only of quotes from the IPCC, the US CCSP and an image from the CCSP report.PielkeUMN04182018
  • Holdren did not mention hurricanes, floods or tornadoes in his 6 pages of response.
  • Holdren’s response blew up the internet (or at least the tiny part of it involving issues related to climate).
  • When the White House posts 6 pages about you, it gets noticed.
  • For my part, in response wrote a blog response which you can read here.
  • In that post I noted:
    • “It is fine for experts to openly disagree. But when a political appointee uses his position not just to disagree on science or policy but to seek to delegitimize a colleague, he has gone too far.”
  • This was, as far as I am aware, the first time that a Science Advisor to the US President used his platform to seek to delegitimize an academic with whom he disagreed.
  • I am aware of no such comparable use of the authority and reach of the White House against a researcher.
  • The fact that I was singled out by the president’s science advisor was not reported on or commented on by the mainstream scientific media. Leading scientific organizations said nothing.
  • I found this pretty amazing, but c’est la vie.
  • If John Marburger, say, had gone after James Hansen, it’d have been a story.
  • I responded more forcefully in an article in The New Republic a few days later.
  • None of this mattered, I quickly learned that a lone academic is no match for the bully pulpit that is the White House and the powerful echo chamber of the online climate debate.
  • A few weeks later the campaign to have me removed as a writer for 538 was underway and 11 months later the investigation motivated by Rep. Raul Grijlava (D-AZ), which he indicated was the result of Holdren’s missive, was launched.
  • One of my close colleagues said to me at the time: “I’d love to come to your defense, but I don’t want them coming after me.”
  • Fair enough.
  • Let’s quickly take a look at the state of the science in 2018 on drought.
  • The 2017 US National Climate Assessment, prepared under the direction of John Holdren in the last months of the Obama Administration and released after Donald Trump became president concluded the following about drought:
    • “drought statistics over the entire CONUS have declined … no detectable change in meteorological drought at the global scale”
    • “Western North America was noted as a region where determining if observed recent droughts were unusual compared to natural variability was particularly difficult.”
  • Right.
  • It was an interesting experience.
  • I’m still here.

via The Climate Fix

April 30, 2018 at 10:13PM

Governor Moonbeam Loses The Plot

Governor Moonbeam Loses The Plot

Here in California, we have one of the more deluded Governors in history, Jerry Brown. He has gotten his sobriquet “Governor Moonbeam” the old fashioned way … he earned it honestly through things like maniacally supporting his multibillion-dollar “Bullet Train To Nowhere“, and plenty more craziness-du-jour.

jerry brown.png

But I never thought that even Governor Moonbeam could be this far detached from reality. Here’s what he said two weeks ago on C-SPAN.

Google ChromeScreenSnapz124.png


So climate now causes terrorism, and that’s just for starters. The real news is that “three billion people”, almost half of the population of the planet, will die from “fatal lethal heat events”.

I suppose that’s as opposed to those dying from non-fatal lethal heat events, but still … say what???

Riiight … welcome to Californistan, where even the Governor is clearly smoking something.


via Watts Up With That?

April 30, 2018 at 06:40PM

Researchers plan biggest ever Antarctic field campaign

The edge of the Thwaites glacier [credit: NASA photograph by Jim Yungel]

This BBC report seems unaware that a study in 2014 found that parts of the Thwaites Glacier are subject to melting due to subglacial volcanoes and other geothermal “hotspots”.

British and American scientists will assess the stability of one of Antarctica’s biggest ice streams, reports BBC News.

It is going to be one of the biggest projects ever undertaken in Antarctica.

UK and US scientists will lead a five-year effort to examine the stability of the mighty Thwaites Glacier.

This ice stream in the west of the continent is comparable in size to Britain. It is melting and is currently in rapid retreat, accounting for around 4% of global sea-level rise – an amount that has doubled since the mid-1990s.

Researchers want to know if Thwaites could collapse. Were it to do so, its lost ice would push up the oceans by 80cm or more.

Some computer models have suggested such an outcome is inevitable if conditions continue as they are – albeit on a timescale of centuries. But these simulations need to be anchored in many more real-world observations, which will now be acquired thanks to the joint initiative announced on Monday.

“There is still a question in my view as to whether Thwaites has actually entered an irreversible retreat,” said Prof David Vaughan, the director of science at the British Antarctic Survey.

“It assumes the melt rates we see today continue into the future and that’s not guaranteed. Thwaites is clearly on the verge of an irreversible retreat, but to be sure we need 10 years more data,” he told BBC News.

The UK’s Natural Environment Research Council and the US National Science Foundation are going to deploy about 100 scientists to Thwaites on a series of expeditions.

The International Thwaites Glacier Collaboration (ITGC) is the two nations’ biggest cooperative venture on the White Continent for more than 70 years – since the end of a mapping project on the Antarctic Peninsula in the late 1940s.

Grants for research totalling £20m have been awarded. Once the costs of transport and resupply to this remotest of regions is factored in, the total value of the ITGC will probably top £40m.

Thwaites is a marine-terminating glacier. Snows fall on land and these compact into ice that then flows out to sea.

Continued here.

via Tallbloke’s Talkshop

April 30, 2018 at 05:18PM