Showing posts with label Jason Box. Show all posts
Showing posts with label Jason Box. Show all posts
Thursday, September 5, 2013
Monday, July 29, 2013
by Peter Sinclair, It's Not Cool, July 29, 2013
Latest video for The Yale Forum on Climate Change & the Media, the first since returning from Greenland – includes interviews with ice expert Alun Hubbard, whom I met in Kangerlussuaq, as well as a snip from Richard Alley, at June’s Chapman conference in Granby, CO, and Jason Box, who spoke from our DarkSnowProject HQ in Sisimiut, in early July.
Takeaway – Greenland represents 22 feet of sea level rise, it’s moving faster than anyone thought it could just a few years ago, and there are processes occurring deep in the ice that may make even faster inevitable. According to Hubbard, we may we witnessing the deglaciation of a major ice sheet, with serious global implications.
Wednesday, July 10, 2013
by gareth renowden, hot topic, july 11, 2013
Massize forest fires are raging beyond control in Quebec, sending huge plumes of smoke to the east. The Eastmain fire — top left in this image from NASA’s Earth Observatory — is spreading towards the east coast of James Bay, the southernmost extension of Hudson Bay, and is currently estimated to cover an area of 656,000 hectares (1.6 million acres). Smoke from the huge fires has already caused smog problems in Montreal and Maine, and is heading round the globe. On July 8 NASA’s Terra satellite spotted a great swathe of Canadian smoke crossing Norway and Sweden, and heading across the Baltic towards Finland.
The Eastmain fire is the largest wildfire in Canada since 1959, and is almost as big as all the wildfires that have burned in the US so far this year. Forecasts for the area show warm temperatures continuing for at least another 5 days, so the fire is likely to continue to spread.
Meanwhile, up on the Greenland ice sheet, Jason Box, Peter Sinclair and the Dark Snow team, who are investigating the effect of smoke particles deposited on the ice on melting, have successfully completed their first sampling mission. It’s well worth checking Sinclair’s blog for frequent updates — and lovely images — of the team’s progress.
Thursday, June 13, 2013
Darkening causes the snow to absorb more sunlight which in turn increases melting
Climate scientist Jason Box during an expedition in Greenland in July 2008. Photograph: Byrd Polar Research Center
by John Abraham, Climate Consensus: the 97%, The Guardian, June 12, 2013
Last July, a record melting occurred on the Greenland ice sheet. Even in some of the highest and coldest areas, field parties observed rainfall with air temperatures several degrees above the freezing point. A month before, it was as though Greenland expert Jason Box had a crystal ball; he predicted this complete surface melting in a scientific publication. Box's research then got broader public visibility after climate activist and writer Bill McKibben covered it in Rolling Stone magazine.
The basic premise of Box's study was that observations reveal a progressive darkening of Greenland ice. Darkening causes the white snow surface to absorb more sunlight which in turn increases melting. Given that this process is likely to continue, the impact on Greenland melt, and subsequent sea level rise, will be profound.
There are several mechanisms that are known to darken arctic ice, including desert dust, pollen, soot from natural forest fires, and human biomass burning for land clearing and domestic use. Industrial, shipping, and aircraft pollution also play a role. Some of these effects are increasing. As climate change accelerates, more areas are being burned by wildfire each year. Box wondered how much increasing wildfires with resulting soot landing on the northern ice might amplify what scientists call a "positive feedback" (a self-reinforcing cycle) increasing Greenland melting. The cycle starts with initial warming, leading to more fires, more soot, and in turn more warming and more melt. The feedback is important, particularly in polar regions where observed warming is twice the rate of more southerly locations around the globe. Box calculates this effect has doubled Greenland surface melting since year 2000.
The topic has become hot among ice experts as new observations of ice melt continue to outstrip projections from just a few years ago. Arctic sea ice, another key measure of global heating, is now 60 years ahead of worst-case projections from the last report by the Intergovernmental Panel on Climate Change in 2007. Arctic snow cover on land has also been declining more rapidly than projected, even faster than sea ice. While mass loss of the enormous Greenland sheet is difficult to measure, satellite data indicate it has doubled in the last decade. If this acceleration continues, sea level rise could be even higher this century than the 1 or 2 meters that mainstream scientists now project – possibly much higher. Despite a recent study that projected Greenland outflow glaciers to slow, surface melting has increased faster than ice flow. The albedo feedback is a critical piece of physics that enables surface melting to continue dominating the loss.
To test his hypothesis, Box has assembled a team of scientists and communicators to collect and analyze samples from key locations on the ice sheet, and report those results directly to the public. The plan is to arrive in Greenland in late June, just as the peak melting season and fire season coincide. Box will be joined by Bill McKibben, who will be covering the research for Rolling Stone, and videographer Peter Sinclair, whose series of climate change videos on YouTube has gained high praise from climate scientists.
The scientific team includes Sara McKenzie Skiles, a researcher at UCLA and the NASA Jet Propulsion Laboratory, and Marek Stibal, a biogeochemist at the Geological Survey of Denmark and Greenland. Dr Stibal will be looking at yet another potential source of darkening, the activity of microorganisms that produce their own darkening pigments, which may be increasing due to atmospheric warming and fertilization by pollutants.
While government funding contracted, Box decided to push forward with a new approach, financing the research as a "citizen science" initiative, funded by internet crowd sourcing. His project is aptly named DARK SNOW and financial support is being collected online.
It is exciting to watch emerging science collide with novel scientific fundraising initiatives. It is possible that this emergence will grow in the coming years as scientific projects grow in cost and complexity, while more traditional funding sources diminish. The costs of funding projects like DARK SNOW are miniscule compared to the costs we endure from climate-change-related weather disasters. The penny-wise pound-foolish attitude we've taken toward science funding is a complicated issue that I'll deal with in a future post.
http://www.guardian.co.uk/environment/climate-consensus-97-per-cent/2013/jun/12/greenland-darkening-ice-climate-science
Last July, a record melting occurred on the Greenland ice sheet. Even in some of the highest and coldest areas, field parties observed rainfall with air temperatures several degrees above the freezing point. A month before, it was as though Greenland expert Jason Box had a crystal ball; he predicted this complete surface melting in a scientific publication. Box's research then got broader public visibility after climate activist and writer Bill McKibben covered it in Rolling Stone magazine.
The basic premise of Box's study was that observations reveal a progressive darkening of Greenland ice. Darkening causes the white snow surface to absorb more sunlight which in turn increases melting. Given that this process is likely to continue, the impact on Greenland melt, and subsequent sea level rise, will be profound.
There are several mechanisms that are known to darken arctic ice, including desert dust, pollen, soot from natural forest fires, and human biomass burning for land clearing and domestic use. Industrial, shipping, and aircraft pollution also play a role. Some of these effects are increasing. As climate change accelerates, more areas are being burned by wildfire each year. Box wondered how much increasing wildfires with resulting soot landing on the northern ice might amplify what scientists call a "positive feedback" (a self-reinforcing cycle) increasing Greenland melting. The cycle starts with initial warming, leading to more fires, more soot, and in turn more warming and more melt. The feedback is important, particularly in polar regions where observed warming is twice the rate of more southerly locations around the globe. Box calculates this effect has doubled Greenland surface melting since year 2000.
The topic has become hot among ice experts as new observations of ice melt continue to outstrip projections from just a few years ago. Arctic sea ice, another key measure of global heating, is now 60 years ahead of worst-case projections from the last report by the Intergovernmental Panel on Climate Change in 2007. Arctic snow cover on land has also been declining more rapidly than projected, even faster than sea ice. While mass loss of the enormous Greenland sheet is difficult to measure, satellite data indicate it has doubled in the last decade. If this acceleration continues, sea level rise could be even higher this century than the 1 or 2 meters that mainstream scientists now project – possibly much higher. Despite a recent study that projected Greenland outflow glaciers to slow, surface melting has increased faster than ice flow. The albedo feedback is a critical piece of physics that enables surface melting to continue dominating the loss.
To test his hypothesis, Box has assembled a team of scientists and communicators to collect and analyze samples from key locations on the ice sheet, and report those results directly to the public. The plan is to arrive in Greenland in late June, just as the peak melting season and fire season coincide. Box will be joined by Bill McKibben, who will be covering the research for Rolling Stone, and videographer Peter Sinclair, whose series of climate change videos on YouTube has gained high praise from climate scientists.
The scientific team includes Sara McKenzie Skiles, a researcher at UCLA and the NASA Jet Propulsion Laboratory, and Marek Stibal, a biogeochemist at the Geological Survey of Denmark and Greenland. Dr Stibal will be looking at yet another potential source of darkening, the activity of microorganisms that produce their own darkening pigments, which may be increasing due to atmospheric warming and fertilization by pollutants.
While government funding contracted, Box decided to push forward with a new approach, financing the research as a "citizen science" initiative, funded by internet crowd sourcing. His project is aptly named DARK SNOW and financial support is being collected online.
It is exciting to watch emerging science collide with novel scientific fundraising initiatives. It is possible that this emergence will grow in the coming years as scientific projects grow in cost and complexity, while more traditional funding sources diminish. The costs of funding projects like DARK SNOW are miniscule compared to the costs we endure from climate-change-related weather disasters. The penny-wise pound-foolish attitude we've taken toward science funding is a complicated issue that I'll deal with in a future post.
http://www.guardian.co.uk/environment/climate-consensus-97-per-cent/2013/jun/12/greenland-darkening-ice-climate-science
Sunday, May 19, 2013
3 part study reconstructs Greenland ice sheet mass budget since 1840 and presents a theory connecting surface meltwater with ice deformational flow
by Jason Box, Melt Factor blog, May 16, 2013
by Jason Box, Melt Factor blog, May 16, 2013
It took 7 years to pull together a full ice sheet mass budget closure based on a fusion of observationally based records from coastal and inland weather station temperature readings; ice cores; and regional climate modeling.
Below are links to pre-prints. The papers’ abstracts capture key results but are constrained by 250-word limits. I emphasize Part III below. Parts I and II were foundational works with interesting aspects. Part III brings in necessary data from parts I and II.
Greenland ice sheet mass balance reconstruction. Part I: net snow accumulation (1600-2009)
Jason E. Box, Noel Cressie, David H. Bromwich, Ji-Hoon Jung, Michiel van den Broeke, J. H. van Angelen, Richard R. Forster, Clement Miège, Ellen Mosley-Thompson, Bo Vinther, Joseph R. McConnell. Abstract. PDF (3210 KB)
Greenland ice sheet mass balance reconstruction. Part II: surface mass balance (1840-2010)
Jason E. Box. Abstract. PDF (3322 KB)
Greenland ice sheet mass balance reconstruction. Part III: marine ice loss and total mass balance (1840-2010). Jason E. Box, William Colgan. Abstract. PDF (2452 KB)
Paper III puts forth a theory* linking surface melting with ice flow dynamics. The two are by now too often examined in isolation. Our not so old science of glaciology, beginning in earnest in the late 1950s, can now begin unifying surface and ice dynamics processes at the ice sheet scale. In stark contrast to the messaging that the recent Nick et al. modeling study produced, we may expect plenty more sea level contribution from Greenland than current models predict. The misreporting of otherwise good science refers to ice flow to the sea as “melt.” Ice deformational flow is a distinct process from melt. Yet, melt and ice deformational flow are in fact intertwined processes. Self-reinforcing amplifying feedbacks outnumbering damping feedbacks by a large margin (Cuffey and Patterson, 2010, chapter 14) ensure that given a climate warming perturbation, a.k.a. the Hockey Stick, we’ll see a stronger response of ice to climate than is currently encoded by models. More on that later.
Because the peak statistical sensitivity between meltwater runoff and ice flow discharge emerges at the decadal scale (11-13 years), it seems that the ice softening due to more meltwater in-flow to the ice sheet -- the Phillips Effect, if you will -- is a central physical process behind a link between runoff and ice flow dynamics (Phillips et al. 2010, 2013).
Yet, on shorter time scales and resulting from a rising trend of surface melting, also to be considered is the effect of meltwater ejection at the underwater front of marine-terminating glaciers. The effect is to force a heat exchange between the glacier front and relatively warm sea water with the ice (Motyka et al. 2003), melting it. This is, if you will, the Motyka Effect. Underwater melting undercuts the glacier front, promoting ice berg calving and thus providing a direct and immediate link between surface runoff and ice flow. Calving reduces flow resistance, causing ice flow acceleration. [Readers, these are two key elements to mass balance theory, with a combined effect I suspect is larger than most previously thought.]
January-February 2013: As I responded to 3 critical anonymous external reviewers and the sands of time were running low to make the 15 March, 2013 deadline for the IPCC AR5, in a bid to increase the likelihood of paper III’s acceptance, I brought on Liam Colgan. His fresh and sharp eyes would comb out any potential text and methodological snags from my major revision. While you may know Liam to be a frequent user of Monte Carlo methods, I already had that in this paper before thinking of his involvement. To his credit, Liam contributed the crevasse-widening aspect to the theory that builds coincidentally via Colgan et al. (2011)’s building on Pfeffer and Bretherton (1987). The Colgan Effect is thus the 3rd aspect of the unified theory this part III study puts forth.
As to the result of the mass budget reconstruction, it’s not surprising that Greenland ice sheet contribution to sea level has accelerated. After all, climate has emerged from the dim-sun Little Ice Age into the greenhouse gas-forced new post-industrial climate epoch, the Anthropocene. Greenland’s going. It’s a question of how fast. I’m happy to report that more to this story is in the works. So, stay tuned.
* A theory is a broad collection of knowledge based on hypotheses (emphasis plural) that have withstood skeptical inquiry and are accepted, unless otherwise proven, as Fact.
J. Climate Editor Anthony J Broccoli deserves thanks for, presumably, working extra in recognition of critical timeline.
Works Cited
- Colgan, W., K. Steffen, W. McLamb, W. Abdalati, H. Rajaram, R. Motyka, T. Phillips, and R. Anderson, 2011a: An increase in crevasse extent, West Greenland: Hydrologic implications, Geophy. Res. Lett. 38, doi:10.1029/2011GL048491
- Cuffey, K.M. and W.S.B. Paterson (2010). The Physics of Glaciers, Fourth Edition. Elsevier, 693 pp.
- Motyka, R. J., L. Hunter, K. A. Echelmeyer, and C. Conner, 2003: Submarine melting at the terminus of a temperate tidewater glacier, LeConte Glacier, Alaska, U.S.A., Ann. Glaciol. 36, 57-65.
- Nick, F.M., A. Vieli, M.L. Andersen, I. Joughin, A. Payne, T.L. Edwards, F. Pattyn and R.S.W. van de Wal, 2013, Future sea-level rise from Greenland’s main outlet glaciers in a warming climate, Nature 497, 235–238 (09 May 2013) doi:10.1038/nature12068
- Pfeffer, W. and C. Bretherton, 1987: The effect of crevasses on the solar heating of a glacier surface, IAHS Publication 170, 191-205.
- Phillips, T., H. Rajaram, and K. Steffen, 2010: Cryohydrologic warming: A potential mechanism for rapid thermal response of ice sheets, Geophys. Res. Lett. 37, L20503, doi:10.1029/2010GL044397.
- Phillips, T., W. Colgan, H. Rajaram and K. Steffen. Evaluation of cryo-hydrologic warming as an explanation for increased ice velocities near the equilibrium line, Southwest Greenland, J. Geophys. Res., 2012JF002584; submitted 7 July 2012, revised 31 December 2012.
Tuesday, May 14, 2013
from Peter Sinclair, Climate Denial Crock of the Week, May 14, 2013
On April 21, 2013, the Dark Snow Project brought a bit of Greenland to Manhattan, to illustrate the importance of this summer’s planned expedition to sample Greenland ice. It kicked off the last leg of our historic citizen-science crowd funding campaign.
If this final fundraising push is successful, I’ll be traveling in June to the Greenland Ice sheet as part of a scientific expedition to investigate the steady darkening and increasing melt of that important ice sheet. Bill McKibben will be coming along to write this up for Rolling Stone, as well.
There are 3 ways to help out, if you haven’t already. One, you can go to Darksnowproject.org, and make a donation at the bottom of the page. Two, you can text darksnow to 50555, or Three, you can go to the IndieGoGo crowdsourcing site.
If this final fundraising push is successful, I’ll be traveling in June to the Greenland Ice sheet as part of a scientific expedition to investigate the steady darkening and increasing melt of that important ice sheet. Bill McKibben will be coming along to write this up for Rolling Stone, as well.
There are 3 ways to help out, if you haven’t already. One, you can go to Darksnowproject.org, and make a donation at the bottom of the page. Two, you can text darksnow to 50555, or Three, you can go to the IndieGoGo crowdsourcing site.
Wednesday, May 8, 2013
by Jason Box, Melt Factor blog, May 3, 2013
A friend in Greenland’s capital Nuuk reported (with a frown) that the backcountry skiing this year was poor due to a “snow drought.”
Figure 1. Western ice sheet snowfall totals are 30%-70% of normal. Brown areas have less than ‘normal’ precipitation. Blue/purple areas are anomalously ‘wet’. The precipitation anomalies are calculated from ‘re-analyses’ data after Kalnay et al. (1996).
Multiple melt factors combine to increase the odds of more melt water runoff from the ice sheet during the 2013 melt season:
Figure 2. The data after Kalnay et al. (1996) indicate tendencies toward offshore flow over western Greenland, opposite for what is needed to produce normal snowfall.
The precipitation anomaly is manifesting in abnormally low land and ice sheet reflectivity (albedo) (Figure 3).
Figure 3. April 2013 surface albedo (a.k.a. reflectivity) anomaly. Substantially lower albedo anomalies on land are due to the dearth of snow revealing a much darker underlying tundra. The red areas across the northern 1/3 of Greenland are uncertain due to low solar illumination angles.
Low snowfall anomalies precondition Greenland ice for enhanced melt (Mote, 2003; Box et al. 2005, 2012), especially for the western ice sheet where the snowfall amounts are less than over the east.
From 20 March to 20 April, the snow drought drove ice sheet reflectivity well below values in 13 years of (NASA MODIS sensor) satellite observations since 2000 (Figure 4). Negative North Atlantic Oscillation (NAO) has promoted Greenland heating, melting and snow drought for now 6 summers in a row (Tedesco et al. 2013, Fettweis et al. 2013). Negative late winter NAO packs a similar punch. Negative NAO has prevailed much of the past decade and is largely to blame for Greenland’s astonishing melt increase. Whether negative NAO is promoted by an earlier loss of snow on land and declining Arctic sea ice area is something I’ve been wondering about.
Figure 4. Greenland ice sheet (land excluded) reflectivity or albedo updated after Box et al. (2012).
Then the weather flipped and ice sheet reflectivity rebounded toward normal values in the latest 10 days (Figure 4). Ice sheet reflectivity and accumulated precipitation remains lower than average for the year to date through 1 May (not shown), it therefore remains more likely than not that we’ll see a big melt in 2013.
http://www.meltfactor.org/blog/?p=860
A friend in Greenland’s capital Nuuk reported (with a frown) that the backcountry skiing this year was poor due to a “snow drought.”
Figure 1. Western ice sheet snowfall totals are 30%-70% of normal. Brown areas have less than ‘normal’ precipitation. Blue/purple areas are anomalously ‘wet’. The precipitation anomalies are calculated from ‘re-analyses’ data after Kalnay et al. (1996).
Multiple melt factors combine to increase the odds of more melt water runoff from the ice sheet during the 2013 melt season:
- less ‘cold content’ of snow to melt away (ablate) for a given energy input before bare ice is exposed;
- a longer period of exposed darker bare ice, in this case weeks earlier bare ice exposure is likely unless a big snow dump before or during the coming warm season;
- Less snow leads to a smaller refreezing capacity in the lower accumulation area. Thanks Robert Fausto of GEUS for reminding me of this one.
- a possible higher concentration of light absorbing impurities per unit volume of snow, assuming that the impurities are deposited whether or not it snows.
Figure 2. The data after Kalnay et al. (1996) indicate tendencies toward offshore flow over western Greenland, opposite for what is needed to produce normal snowfall.
The precipitation anomaly is manifesting in abnormally low land and ice sheet reflectivity (albedo) (Figure 3).
Figure 3. April 2013 surface albedo (a.k.a. reflectivity) anomaly. Substantially lower albedo anomalies on land are due to the dearth of snow revealing a much darker underlying tundra. The red areas across the northern 1/3 of Greenland are uncertain due to low solar illumination angles.
Low snowfall anomalies precondition Greenland ice for enhanced melt (Mote, 2003; Box et al. 2005, 2012), especially for the western ice sheet where the snowfall amounts are less than over the east.
From 20 March to 20 April, the snow drought drove ice sheet reflectivity well below values in 13 years of (NASA MODIS sensor) satellite observations since 2000 (Figure 4). Negative North Atlantic Oscillation (NAO) has promoted Greenland heating, melting and snow drought for now 6 summers in a row (Tedesco et al. 2013, Fettweis et al. 2013). Negative late winter NAO packs a similar punch. Negative NAO has prevailed much of the past decade and is largely to blame for Greenland’s astonishing melt increase. Whether negative NAO is promoted by an earlier loss of snow on land and declining Arctic sea ice area is something I’ve been wondering about.
Figure 4. Greenland ice sheet (land excluded) reflectivity or albedo updated after Box et al. (2012).
Then the weather flipped and ice sheet reflectivity rebounded toward normal values in the latest 10 days (Figure 4). Ice sheet reflectivity and accumulated precipitation remains lower than average for the year to date through 1 May (not shown), it therefore remains more likely than not that we’ll see a big melt in 2013.
http://www.meltfactor.org/blog/?p=860
Friday, April 19, 2013
Here’s what I know so far.
The Dark Snow Project is on track, and will jump to a new level of seriousness this weekend, as we point toward a data gathering trip slated for peak melt season in Greenland this summer.
I have confirmation that writer/activist Bill McKibben will be joining Greenland expert Dr. Jason Box and myself early in the trip. With Dr. Box’s expert guidance, we’ll be taking a closer look at some of the most sensitive and important features of the Greenland sheet. More on this as details become available.
Meanwhile, this weekend, darksnow awareness-and-fund raising continues in an Earth Day event in Union Square in Manhattan, New York City – as Dr Box and I, along with thousands of others, will be observing a massive darksnow themed ice sculpture illustrating the effects of darkening on the Greenland ice sheet.http://climatecrocks.com/2013/04/19/bill-mckibben-to-join-dark-snow-project-in-greenland/
Tuesday, April 16, 2013
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Independent video producer Peter Sinclair trains his lens and microphone on seven climate science experts to help explain ice melt in Greenland and its implications for sea-level rise over remainder of the century.
Powerful graphics and concise interviews with expert climate scientists combine in independent video producer Peter Sinclair’s monthly Yale Forum “This Is Not Cool” video on Greenland ice melt.
The video includes interviews and sound clips featuring NASA climate scientists; Nichols College, Ohio State and Penn State scientists; and a Climate Institute scientist. Among other points, these experts cite the benefits of having ice melt maps over the past two decades and point to the intensity, and not necessarily the geographical extent, of Greenland ice sheet melting as a particular concern.
“Exceptional melts” is how one expert characterizes recent Greenland melting … “very well documented” by satellite records. “A 10-year doubling time” on Greenland’s sea-level contribution “makes it much more likely that we will observe more than one meter of sea-level rise by the end of the century,” a scientist observes. Another scientist’s counsel: “A big dip in 2012. We don’t know what’s going to happen in 2013.”
“Just astounding to see,” a glaciologist cautions … “we just have more melt everywhere.”
“A very serious issue,” another concludes.
The video is one of a continuing series that Sinclair produces exclusively for The Yale Forum.
Link: http://www.yaleclimatemediaforum.org/2013/04/yale-forum-monthly-video-focuses-on-greenland-ice-sheet-melt/
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