Guest opinion: Dr. Tim Ball
Glaciers are in the news again. An article by James Hansen about Antarctica and another published by Geophysical Research Letters about Greenland raise the specter of sea level rise. They are purely speculative and don’t bear investigation, but that doesn’t matter because the headline is the objective. The wider purpose and the reason glaciers are the target is the upcoming climate Conference of the Parties (COP21) scheduled for Paris in November. Polls show the lack of public concern about global warming or climate change, which necessitated a return to a tried and successful alarmist strategy.
Hansen’s article focuses on the West Antarctic Ice Sheet (WAIS), which was the NASA focus from the start.
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.
NASA promotes the same message now, except they are not as certain as Hansen.
Even as Rignot and colleagues suggest that loss of the Amundsen Sea embayment glaciers appears inevitable, it remains extremely difficult to predict exactly how this ice loss will unfold and how long it will take. A conservative estimate is that it could take several centuries.
The region contains enough ice to raise global sea levels by 4 feet (1.2 meters).
The trouble is they don’t explain the calculation. Presumably, it is all the ice above and below sea level, but it doesn’t matter it is a big enough number to raise an alarm.
When I ask people what is wrong with global warming, they pause, often for some time, before saying, glaciers melting and sea level rising. It is foremost in their minds because of the exploitation in Al Gore’s movie. A study of public climate knowledge by Yale researchers illustrates the point (Figure 1).
The question is, “Which of the following can cause global sea levels to rise? (order of items randomized.)”
The correct answers, according to the Yale researchers, are given in brackets as True (T), or False (F). No wonder, in the overall results, 77 percent failed (Figure 2).
In the options, it is illogical to claim Arctic Ocean ice melting. If you claim Arctic sea ice causes sea level change, then why not Antarctic sea ice? Of course, claiming either is wrong because the ice is formed from seawater. There is likely a minimal sea level change because the ice is 6-7 percent greater in volume, but that is likely balanced because a portion of the sea ice is above sea level. Majorities of the 76 percent who believe melting Arctic sea ice raises sea level, likely do so because of the Gore deception. It is why the animation sequences of water over-running the land are a major part of the movie. He added the false emotive factor of drowning polar bears for a persuasive combination.
Other options for a source of melt water to raise global sea level are equally limited. They don’t mention Greenland or changes in the isostatic balance of land. The options and answers reflect the simplistic and fallacious arguments about sea level. Estimates of the total ice and water it contained produced a volume of water then added to existing sea level. Here is an exercise circulated for teachers by NASA in 1997.
Exercise: Determine the amount that sea level would rise, averaged around the globe, in response to the complete melting of (a) the Greenland ice sheet, (b) the Antarctic ice sheet, and (c) both the Greenland and Antarctic ice sheets.
The exercise offers some discussion of limitations but results in the following numbers.
(4) Calculate the sea-level-rise answers by dividing the water volumes determined in #3 by the global surface-water area determined in #1, thereby spreading the effect of the ice sheet’s water throughout the expanse of the Earth’s surface-water area. The answers are: (a) (2,343,728 cubic kilometers)/(361,132,000 square kilometers) = 0.0065 kilometers = 6.5 meters for the Greenland ice sheet; (b) (26,384,368 cubic kilometers)/(361,132,000 square kilometers) = 0.0731 kilometers = 73.1 meters for the Antarctic ice sheet; (c) 6.5 meters + 73.1 meters = 79.6 meters for Greenland and Antarctica together.
So there is the much-cited number of 79.6 meters (261 feet) that you add to existing levels. This sticks in students memories, despite warnings by the exercise creators that,
No knowledgeable person expects the Greenland and Antarctic ice sheets to disappear completely within the lifetime of anyone alive today, or within the lifetime of any of their children or grandchildren. Hence, the threat of a 79.6- meter sea level rise should not be seen as an immediate concern.
Thank goodness! But the relief is short-lived because the final paragraph identifies some limitations, but alarmism remains central.
These two ice sheets, however, are the largest potential contributors to sea level rise, and concern has been raised in particular over the possibility that the portion of the Antarctic ice sheet termed the West Antarctic ice sheet, lying largely in the western hemisphere, might be unstable and might decay relatively rapidly, perhaps even causing sea level rises of several meters within 100 years. Although such a decay is not highly probable, it is possible, and if it were to occur, the resulting several-meter sea level rise would cause serious economic and personal consequences to all highly populated low- lying coastal regions.
The actual exercise requires determining what percentage of the ice in the Greenland and Antarctic ice sheets is above sea level. Only melt water from that ice can contribute to sea level rise. An adjustment is necessary because the volume of the ice is approximately 6% more than the volume of the melt water. Then you have to calculate and allow for crustal deformation and isostatic adjustment for a reasonably accurate measure.
A few years ago, before it became politically motivated, Scientific American produced useful overview articles, such as John Eddy’s the Case of the Missing Sunspots. A March 1997 article asked, “How much of a threat are rising sea levels.
Now, 16 years after the NASA exercise, the 2013 Intergovernmental Panel on Climate Change (IPCC) Report Physical Science Basis Report concludes,
Therefore, the closure of the sea level budget to date does not test the reliability of ice-sheet models in projecting future rapid dynamical change; we have only medium confidence in these models, on the basis of theoretical and empirical understanding of the relevant processes and observations of changes up to the present.
The Report identifies some of the limitations.
They identify three categories of confidence, Low, Medium, and High. Do we assume that Medium is 50 percent? It is reasonable considering the limitations they identify.
Nevertheless, three central issues remained. First, the observed sea level rise over decades was larger than the sum of the individual contributions estimated from observations or with models (Rahmstorf et al., 2007, 2012a), although in general the uncertainties were large enough that there was no significant contradiction. Second, it was not possible to make confident projections of the regional distribution of sea level rise. Third, there was insufficient understanding of the potential contributions from the ice sheets. In particular, the AR4 recognized that existing ice-sheet models were unable to simulate the recent observations of ice-sheet accelerations and that understanding of ice-sheet dynamics was too limited to assess the likelihood of continued acceleration or to provide a best estimate or an upper bound for their future contributions.
Typically, the Summary for Policymakers (SPM) tells a very different story.
Anthropogenic influences have very likely contributed to Arctic sea-ice loss since 1979 and have very likely made a substantial contribution to increases in global upper ocean heat content (0–700 m) and to global mean sea level rise observed since the 1970s
“Very Likely” is 90 – 100 %.
It is another example of the deliberate deception created by great differences between the Science Report and the SPM.
It is impossible to discuss all the limitations of IPCC analysis of glacier changes that result in sea level change. Figure 3 from the IPCC AR5 Science Report shows the extent of the variables.
Science distinguishes between Mountain (Alpine) and continental glaciers. In reality, the creation and mechanisms are the same Temperature receives most of the focus and public understanding about glaciers. However, precipitation is equally important information and changes in what is called the Mass Balance of the glacier. The front of the glacier, called the snout in mountain glaciers, advances or retreats as much because of precipitation as temperature.
A glacier forms when some snow survives the summer melt. That can occur because of lower temperatures or an increase in the volume of snow. Figure 4 shows the dynamic balance of a glacier.
The Equilibrium line moves with temperature but because of the gradient it takes a considerable change for it to move much and affect a significant area. A more significant factor is the change in the amount of snow in the accumulation zone.
Obviously snowfall amounts vary in different regions and over time. This explains why glaciers in some regions advance while others retreat.
Scientists track glacial change by measuring individual glaciers and comparing their size over time with records of the local and regional climate. But measuring every major glacier on Earth would be a monumental task. Approximately 160,000 glaciers occupy the Earth’s polar regions and high mountain environments, and sending a team to each one every year would be costly and difficult to coordinate. In addition, although a few research teams travel to a few glaciers each year to measure ice depth, size, movement, and water content, the data from individual glaciers don’t necessarily reveal how other glaciers in the same region—much less in other parts of the world—are changing. Even glaciers within the same region can react differently to environmental changes. For example, while most glaciers in Glacier National Park are retreating, some are advancing.
The difficulty is biased reporting, as only retreating glaciers make the headlines.
NASA is planning for better knowledge of the mass balance of Antarctica with a satellite.
In 2017, NASA will launch ICESat-2, the follow-up mission to ICESat, which operated from 2003 to 2009. ICESat-2 will use laser altimetry to make precise measurements of glacier heights. Combined with the ICESat and IceBridge data records, the ICESat-2 measurements will allow for a continuous record of year-over-year change in some of the most remote regions of the world.
The problem is the height of an ice mass like Antarctica is not an indicator of changing size or volume. As the mass at the center of the glacier increases the outward flow increases, thus reducing central mass and height (Figure 5).
A 2012 article titled “Why ice loss and sea level measurements via satellite and the new Shepherd et al. paper are highly uncertain at the moment” spoke to the problems with the NASA claims.
The pattern created by the plastic flow of the ice is repeated in a Mountain Glacier, with sagging in the upper portion and bulging in the lower portion because of the plastic flow of the ice. (Figure 6)
Another study reported by WUWT indicates a significant increase in snowfall over the East Antarctic Ice Sheet (EAIS).
Enhanced snowfall on the East Antarctic ice sheet is projected to significantly mitigate 21st century global sea level rise. In recent years (2009 and 2011), regionally extreme snowfall anomalies in Dronning Maud Land, in the Atlantic sector of East Antarctica, have been observed. It has been unclear, however, whether these anomalies can be ascribed to natural decadal variability, or whether they could signal the beginning of a long-term increase of snowfall.
Sea level rise due to melting ice is the one threat of global warming that worked effectively with the public. As the Paris Conference looms the alarmists increase the potential threats to ensure that action is taken. Hansen is one of the most active alarmists who used his position at NASA GISS to push alarmism and misinformation.
A moment of serendipity occurred while researching this article. I typed the acronym WAIS into a search engine expecting West Antarctic Ice Sheet instead I got the Weschler Adult Intelligence Scale. Here is the definition.
… the global capacity of a person to act purposefully, to think rationally, and to deal effectively with his environment.”] He (Weschler) believed that intelligence was made up of specific elements that could be isolated, defined, and subsequently measured. However, these individual elements were not entirely independent, but were all interrelated. His argument, in other words, is that general intelligence is composed of various specific and interrelated functions or elements that can be individually measured.
It appears those studying WAIS are low on the WAIS scale.