Climate Change Science - Ice Melting
|Title:|| ||Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous
|Date of publication:|| ||22 March 2016|
|Description/subject:|| ||Abstract. "We use numerical climate simulations, paleoclimate data, and modern observations to study the effect of growing ice melt from Antarctica and Greenland. Meltwater tends to stabilize the ocean column, inducing amplifying feedbacks that increase subsurface ocean warming and ice shelf melting. Cold meltwater and induced dynamical effects cause ocean surface cooling in the Southern Ocean and North Atlantic, thus increasing Earth's energy imbalance and heat flux into most of the global ocean's surface. Southern Ocean surface cooling, while lower latitudes are warming, increases precipitation on the Southern Ocean, increasing ocean stratification, slowing deepwater formation, and increasing ice sheet mass loss. These feedbacks make ice sheets in contact with the ocean vulnerable to accelerating disintegration. We hypothesize that ice mass loss from the most vulnerable ice, sufficient to raise sea level several meters, is better approximated as exponential than by a more linear response. Doubling times of 10, 20 or 40 years yield multi-meter sea level rise in about 50, 100 or 200 years. Recent ice melt doubling times are near the lower end of the 10–40-year range, but the record is too short to confirm the nature of the response. The feedbacks, including subsurface ocean warming, help explain paleoclimate data and point to a dominant Southern Ocean role in controlling atmospheric CO2, which in turn exercised tight control on global temperature and sea level. The millennial (500–2000-year) timescale of deep-ocean ventilation affects the timescale for natural CO2 change and thus the timescale for paleo-global climate, ice sheet, and sea level changes, but this paleo-millennial timescale should not be misinterpreted as the timescale for ice sheet response to a rapid, large, human-made climate forcing. These climate feedbacks aid interpretation of events late in the prior interglacial, when sea level rose to +6–9 m with evidence of extreme storms while Earth was less than 1 °C warmer than today. Ice melt cooling of the North Atlantic and Southern oceans increases atmospheric temperature gradients, eddy kinetic energy and baroclinicity, thus driving more powerful storms. The modeling, paleoclimate evidence, and ongoing observations together imply that 2 °C global warming above the preindustrial level could be dangerous. Continued high fossil fuel emissions this century are predicted to yield (1) cooling of the Southern Ocean, especially in the Western Hemisphere; (2) slowing of the Southern Ocean overturning circulation, warming of the ice shelves, and growing ice sheet mass loss; (3) slowdown and eventual shutdown of the Atlantic overturning circulation with cooling of the North Atlantic region; (4) increasingly powerful storms; and (5) nonlinearly growing sea level rise, reaching several meters over a timescale of 50–150 years. These predictions, especially the cooling in the Southern Ocean and North Atlantic with markedly reduced warming or even cooling in Europe, differ fundamentally from existing climate change assessments. We discuss observations and modeling studies needed to refute or clarify these assertions"......
James Hansen, Makiko Sato, Paul Hearty, Reto Ruedy, Maxwell Kelley, Valerie Masson-Delmotte, Gary Russell, George Tselioudis, Junji Cao, Eric Rignot, Isabella Velicogna, Blair Tormey, Bailey Donovan, Evgeniya Kandiano, Karina von Schuckmann, Pushker Kharecha, Allegra N. Legrande, Michael Bau, and Kwok-Wai Lo|
|Author/creator:|| ||James Hansen et al|
|Source/publisher:|| ||"Atmospheric Chemistry and Physics"|
|Format/size:|| ||html, pdf (7.2MB-reduced version; 13.4MB-original))|
|Alternate URLs:|| ||https://www.atmos-chem-phys.net/16/3761/2016/acp-16-3761-2016.pdf
|Date of entry/update:|| ||25 June 2016|
|Title:|| ||The New Normal, Super Storms, High Tides and Rising Seas (video)
|Date of publication:|| ||11 March 2016|
|Description/subject:|| ||"This is the story of the century. We have passed a tipping point and are now in a new era – one where the melting of global ice sheets will dramatically transform our world.
John clearly explains the latest science and puts sea level rise into a historical perspective. He then paints a vivid picture of what we can expect in the future, the potential solutions and what we must do now to create resilient cities and communities.
In this enlightening presentation you’ll learn:
Why sea level rise is now unstoppable
The realistic projections over the coming decades
Why the triple threat from storms, tides and sea level rise is producing deadly floods
Why real estate values will go “underwater” long before the property does
Some of the potential business opportunities that could benefit our economy
Why communities, businesses and individuals must start planning and adapting now
Higher Sea Levels Mean Big Risk and Big Business Opportunities
Businesses need to have the latest information on how sea level rise is going to impact their assets and supply chains in coastal zones around the world. Seeing what lies ahead can reduce risk and identify potential new business opportunities. John highlights the realistic projections that can impact an organization’s bottom line, because today the most important line in business is the shoreline.
Rising Seas: Community Planning for a new era
Municipalities in coastal zones and on tidal rivers must now plan for a full range of flooding scenarios from the interplay of storms, tides and sea level rise. John explains how good planning needs to consider short, medium and long range time scales to create cost effective resiliency..."|
|Author/creator:|| ||John Englander|
|Source/publisher:|| ||The Real Truth About Health Conference|
|Format/size:|| ||Adobe Flash (1 hour 28 minutes)|
|Alternate URLs:|| ||https://www.youtube.com/watch?v=7FzFMgeDOCU
|Date of entry/update:|| ||23 January 2017|
|Title:|| ||Melting Ice, Rising Seas - 4 presentations. (videos)
|Date of publication:|| ||13 January 2016|
|Description/subject:|| ||Melting Ice, Rising Seas (Part One) - Prof Jonathan Bamber, Introduced by Prof Bryan Storey...
Melting Ice, Rising Seas (Part Two) - Dr Steve Rintoul, Research Team Leader, CSIRO Australia...
Melting Ice, Rising Seas (Part Three) - Director of the Antarctic Research Centre...
Melting Ice, Rising Seas (Part Four) - Prof Rob DeConto, University of Massachusetts|
|Author/creator:|| ||Prof Jonathan Bamber, Dr Steve Rintoul, Tim Naish, Prof Rob DeConto|
|Source/publisher:|| ||The Antarctic Report - Royal Society of New Zealand|
|Format/size:|| ||Adobe Flash|
|Alternate URLs:|| ||https://www.antarcticreport.com/|
|Date of entry/update:|| ||24 January 2017|
|Title:|| ||Chasing Ice (video)
|Date of publication:|| ||December 2015|
|Description/subject:|| ||"The melting fresh water from glaciers alters the ocean, not only by directly contributing to the global sea level rise, but also because it pushes down the heavier salt water, thereby changing what scientists call the THC, or Thermo (heat) Haline (salt) Circulation, meaning currents in the ocean. This has an immediate effect on the near region, such as the north Atlantic off the coast of Greenland, but ultimately the impacts can ripple far beyond the immediate area and climate.
Ice that took centuries to develop can vanish in just a few years. A glacier doesn’t melt slowly and steadily like an ice cube on a table. Once glacial ice begins to break down, the interaction of meltwater and sea water with the glacier’s structure can cause increasingly fast melting and retreat. Today, Earth’s surface is made up of 71% water, 10% ice and 19% land. Most of the world’s ice is in the Arctic and Antarctic, but some of it is scattered around Earth in the form of mountain glaciers..."|
|Author/creator:|| ||James Balog|
|Source/publisher:|| ||PBS viaYoutube|
|Format/size:|| ||html, Adobe Flash|
|Alternate URLs:|| ||http://www.pbs.org/wgbh/nova/nature/photographing-earths-melting-ice.html
|Date of entry/update:|| ||09 December 2016|
|Title:|| ||How The Antarctic Ice Sheet Is Changing & Why It Matters: An Interview with Martin Siegert
|Date of publication:|| ||11 November 2015|
|Description/subject:|| ||"Antarctica's ice sheet contains enough water to rise sea-levels by over 60 meters, yet we know surprisingly little about the frozen continent to our south. In fact we know more about the surface of Mars than we do the topography of Antarctica. In a live interview in Birmingham with Glaciologist Dr. Martin Siegert, in this episode of The Elephant, we learn the innovative ways in which scientists are studying the ice-sheet, why it matters for the future of the world, and hear about the mysterious sub-glacial lakes that lie buried beneath kilometers of ice"
For more interviews exploring our changing climate, head to www.elephantpodcast.org
subscribe in iTunes at: http://bit.ly/elephantpod|
|Author/creator:|| ||Martin Siegert|
|Source/publisher:|| ||The Elephant/Grantham Research Institute,|
|Format/size:|| ||Adobe Flash (59 minutesd, 21 minutes)|
|Date of entry/update:|| ||27 January 2017|
|Title:|| ||Six degrees could change the world (video)
|Date of publication:|| ||10 February 2008|
|Description/subject:|| ||As the volume of greenhouse gases increases yearly, scientists are warning that the global average temperature could increase by as much as 6 degrees Celsius over the next century, which would cause our world to change radically. This documentary joins British author Mark Lynas and climate experts as they take a look at what effect each rise of 1ºC could have on the world.
Even if greenhouse emissions stopped overnight, the concentrations already in the atmosphere would still mean a global rise of between 0.5 and 1ºC. But what if the global temperature increased by another degree? According to Mark Lynas, author of Six Degrees, the changes would no longer be gradual. Greenland’s glaciers and some of the lower lying islands would start to disappear. At 3ºC higher the Arctic would be ice-free all summer, the Amazon rainforest would begin to dry out and extreme weather patterns would become the norm. An increase of 4ºC would see the oceans rise drastically. Then comes the twilight zone of climate change, if the global temperature rises again by another degree. Part of once temperate regions could become uninhabitable, while humans fight each other for the world’s remaining resources. The sixth degree is what is called the doomsday scenario as oceans become marine wastelands, deserts expand and catastrophic events become more common.
If we do nothing to reduce this threat, where will the tipping point be that may mean we are no longer able to stop global warming?..."|
|Author/creator:|| ||Mark Lynas (author)|
|Source/publisher:|| ||National Geographic|
|Format/size:|| ||Adobe Flash|
|Alternate URLs:|| ||http://www.altenergymag.com/content.php?post_type=1413
|Date of entry/update:|| ||09 December 2016|