The underestimation at issue includes the notion of "tipping points."
These are historical points along the way of climate change, high tide lines in the sand if you will, which, if crossed over will initiate events that cannot be reversed or stopped.
Such tipping point events, if triggered, will play out completely no matter what we do even when we wise up and change our minds about destroying civilization by committing global ecocide.
"Table 1" below shows ice cap locations, volume of ice at those locations, and the potential sea level rise, in feet, should ice at that location completely melt.
Table 1. Estimated potential maximum sea-level rise from the total melting of present-day glaciers and polar ice caps. Source: USGS
|Potential sea-level rise, |
|East Antarctic ice sheet|| |
|West Antarctic ice sheet|| |
|Antarctic Peninsula|| |
|All other ice caps, ice fields, and valley glaciers|| |
Thus, the policy concerning The Damaged Global Climate System should not be to make conservative estimates, rather, it should be to err or the safe side so as to avoid reaching all of those tipping points.
This has been made obvious by a very recent NASA report concerning the Western Ice Sheet in Antarctica, because one local tipping point there has been reached and crossed, which will have global impact:
The new finding that the eventual loss of a major section of West Antarctica's ice sheet "appears unstoppable" was not completely unexpected by scientists who study this area. The study, led by glaciologist Eric Rignot at NASA's Jet Propulsion Laboratory, Pasadena, California, and the University of California, Irvine, follows decades of research and theory suggesting the West Antarctic Ice Sheet is inherently vulnerable to change.(The 'Unstable' West Antarctic Ice Sheet: A Primer, emphasis added). Let's call it the "goodbye Kiribati" and "goodbye Florida" tipping point.
Antarctica is so harsh and remote that scientists only began true investigation of its ice sheet in the 1950s. It didn't take long for the verdict on the West Antarctic Ice Sheet to come in. "Unstable," wrote Ohio State University glaciologist John Mercer in 1968. It was identified then and remains today the single largest threat of rapid sea level rise.
The region contains enough ice to raise global sea levels by 4 feet (1.2 meters). The most recent U.N. Intergovernmental Panel on Climate Change (IPCC) report estimates that by 2100, sea level will rise somewhere from just less than 1 foot to about 3 feet (26 to 98 centimeters). But the vast majority of these projections do not take into account the possibility of major ice loss in Antarctica. Rignot said this new study suggests sea level rise projections for this century should lean toward the high-end of the IPCC range.
The Amundsen Sea region is only a fraction of the whole West Antarctic Ice Sheet, which if melted completely would raise global sea level by about 16 feet (5 meters).
This event was predicted, that is, we were warned in 1978 (West Antarctic ice sheet and CO2 greenhouse effect: a threat of disaster).
To underscore the contrast let's also consider the mentality that is sinking in Florida:
Marco Rubio, as you may have heard, has issued yet another blunt rejection of the whole notion of man-made climate change. “Well, yeah, I don't agree with the notion that some are putting out there, including scientists, that somehow there are actions we can take today that would actually have an impact on what's happening in our climate,” he said yesterday on ABC’s “This Week.” He continued:(The New Republic). At some time we will have to say goodbye to two denier Senators, Rubio and Inhofe, but in the mean time they will continue to urge us to deny climate change as they vote against remedial attempts.
“Our climate is always changing. And what they have chosen to do is take a handful of decades of research and say that this is now evidence of a longer-term trend that's directly and almost solely attributable to man-made activities…I don't know of any era in world history where the climate has been stable. Climate is always evolving, and natural disasters have always existed… I do not believe that human activity is causing these dramatic changes to our climate the way these scientists are portraying it. That's what I—and I do not believe that the laws that they propose we pass will do anything about it, except it will destroy our economy.”For this, Rubio has been roundly ridiculed by reality-based commentators. But even their scorn seems to skip over what is perhaps the most remarkable aspect of Rubio’s evasion on climate change. It would be one thing if Rubio was trying to downplay man-made climate change if he was the senator from a state that is greatly dependent on drawing fossil fuels out of the earth and pumping carbon dioxide into the atmosphere—say, Oklahoma or West Virginia or North Dakota. But Rubio represents Florida, and is in fact from Miami. Which—how to say this nicely?—is in the process of drowning.
The next issue concerning this one Antarctic tipping point we have already reached, is when the impact on us will be noticable ("When": The Most Unstable Adverb?),
The answer to that question is "yesterday", i.e., it is already happening:
These glaciers already contribute significantly to sea level rise, releasing almost as much ice into the ocean annually as the entire Greenland Ice Sheet. They contain enough ice to raise global sea level by 4 feet (1.2 meters) and are melting faster than most scientists had expected. Rignot said these findings will require an upward revision to current predictions of sea level rise.(West Antarctic Glacier Loss Appears Unstoppable). The next "when" is how long it will take to fully melt and cause sea level to rise sixteen feet.
"This sector will be a major contributor to sea level rise in the decades and centuries to come," Rignot said. "A conservative estimate is it could take several centuries for all of the ice to flow into the sea."
A figure which will be added to the sea level rise caused by the Greenland Ice Cap melt, which is also accelerating:
Stability in the rapidly changing Arctic is a rarity. Yet for years researchers believed the glaciers in the frigid northeast section of Greenland, which connect to the interior of the country’s massive ice sheet, were resilient to the effects of climate change that have affected so much of the Arctic.(New Greenland Ice Melt, emphasis added). The gross historical underestimations of both Antarctic and Arctic ice cap melt are quite well known.
But new data published Sunday in Nature Climate Change reveals that over the past decade, the region has started rapidly losing ice due to a rise in air and ocean temperatures caused in part by climate change. The increased melt raises grave concerns that sea level rise could accelerate even faster than projected, threatening even more coastal communities worldwide.
The stability of the region is particularly important because it has much deeper ties to the interior ice sheet than other glaciers on the island. If the entire ice sheet were to melt -- which would take thousands of years in most climate change scenarios -- sea levels would rise up to 23 feet, catastrophically altering coastlines around the world.
Doubling the estimations, because of the increasing rate of acceleration, may even be overly conservative, but a rough calculation indicates a one foot per decade sea level rise average, or about 8.6 feet sea level rise total, by or before 2100.
The ramifications of that are catastrophic in the sense that tipping points are being crossed which have unintended consequences, and in the sense that the U.S. government appears to be paralysed and unable to react responsibly:
Secretary of State John Kerry recently gave a speech in Jakarta, Indonesia, where he compared climate change to other transnational security threats such as “terrorism, epidemics, poverty, [and] the proliferation of weapons of mass destruction.” But the U.S. military was already there.(Secretary Kerry Follows the Military’s Lead on Climate Change). As Dredd Blog has expected for years, the government plan or policy is still triage (New Climate Catastrophe Policy: Triage).
Secretary Kerry was following the lead of four-star Navy Admiral Samuel J. Locklear II, head of U.S. Pacific Command (PACOM), who in a speech in Jakarta a year earlier also identified climate change as the biggest security threat facing the region, with the capacity to even “threaten the loss of entire nations.”
And just last November, Secretary Kerry’s counterpart in the Department of Defense, Chuck Hagel, asserted that climate change “can significantly add to the challenges of global instability, hunger, poverty, and conflict.”
Indeed, while the U.S. Congress is still locked in a partisan debate over climate change, the U.S. military is already taking a proactive approach to this national security threat. In Asia, U.S. Pacific Command is working with China, India and other regional allies to align military capabilities for “when the effects of climate change start to impact these massive populations.”
The previous post in this series is here.
Last Week Tonight: The real way for the news media to show fairness: