Tag Archives: climate change

Predictive Models in Medicine and Health – Forecasting Epidemics

I’m interested in everything under the sun relating to forecasting – including sunspots (another future post). But the focus on medicine and health is special for me, since my closest companion, until her untimely death a few years ago, was a physician. So I pay particular attention to details on forecasting in medicine and health, with my conversations from the past somewhat in mind.

There is a major area which needs attention for any kind of completion of a first pass on this subject – forecasting epidemics.

Several major diseases ebb and flow according to a pattern many describe as an epidemic or outbreak – influenza being the most familiar to people in North America.

I’ve already posted on the controversy over Google flu trends, which still seems to be underperforming, judging from the 2013-2014 flu season numbers.

However, combining Google flu trends with other forecasting models, and, possibly, additional data, is reported to produce improved forecasts. In other words, there is information there.

In tropical areas, malaria and dengue fever, both carried by mosquitos, have seasonal patterns and time profiles that health authorities need to anticipate to stock supplies to keep fatalities lower and take other preparatory steps.

Early Warning Systems

The following slide from A Prototype Malaria Forecasting System illustrates the promise of early warning systems, keying off of weather and climatic predictions.

  malaria                     

There is a marked seasonal pattern, in other words, to malaria outbreaks, and this pattern is linked with developments in weather.

Researchers from the Howard Hughes Medical Institute, for example, recently demonstrated that temperatures in a large area of the tropical South Atlantic are directly correlated with the size of malaria outbreaks in India each year – lower sea surface temperatures led to changes in how the atmosphere over the ocean behaved and, over time, led to increased rainfall in India.

Another mosquito-borne disease claiming many thousands of lives each year is dengue fever.

And there is interesting, sophisticated research detailing the development of an early warning system for climate-sensitive disease risk from dengue epidemics in Brazil.

The following exhibits show the strong seasonality of dengue outbreaks, and a revealing mapping application, showing geographic location of high incidence areas.

dengue

This research used out-of-sample data to test the performance of the forecasting model.

The model was compared to a simple conceptual model of current practice, based on dengue cases three months previously. It was found that the developed model including climate, past dengue risk and observed and unobserved confounding factors, enhanced dengue predictions compared to model based on past dengue risk alone.

MERS

The latest global threat, of course, is MERS – or Middle East Respiratory Syndrome, which is a coronavirus, It’s transmission from source areas in Saudi Arabia is pointedly suggested by the following graphic.

MERS

The World Health Organization is, as yet, refusing to declare MERS a global health emergency. Instead, spokesmen for the organization say,

..that much of the recent surge in cases was from large outbreaks of MERS in hospitals in Saudi Arabia, where some emergency rooms are crowded and infection control and prevention are “sub-optimal.” The WHO group called for all hospitals to immediately strengthen infection prevention and control measures. Basic steps, such as washing hands and proper use of gloves and masks, would have an immediate impact on reducing the number of cases..

Millions of people, of course, will travel to Saudi Arabia for Ramadan in July and the hajj in October. Thirty percent of the cases so far diagnosed have resulted in fatalties.

Links – April 26, 2014

These Links help orient forecasting for companies and markets. I pay particular attention to IT developments. Climate change is another focus, since it is, as yet, not fully incorporated in most longer run strategic plans. Then, primary global markets, like China or the Eurozone, are important. I usually also include something on data science, predictive analytics methods, or developments in economics. Today, I include an amazing YouTube of an ape lighting a fire with matches.

China

Xinhua Insight: Property bubble will not wreck China’s economy

Information Technology (IT)

Thoughts on Amazon earnings for Q1 2014

Amazon

This chart perfectly captures Amazon’s current strategy: very high growth at 1% operating margins, with the low margins caused by massive investment in the infrastructure necessary to drive growth. It very much feels as though Amazon recognizes that there’s a limited window of opportunity for it to build the sort of scale and infrastructure necessary to dominate e-commerce before anyone else does, and it’s scraping by with minimal margins in order to capture as much as possible of that opportunity before it closes.

Apple just became the world’s biggest-dividend stock

Apple

The Disruptive Potential of Artificial Intelligence Applications Interesting discussion of vertical search, virtual assistants, and online product recommendations.

Hi-tech giants eschew corporate R&D, says report

..the days of these corporate “idea factories” are over according to a new study published by the American Institute of Physics (AIP). Entitled Physics Entrepreneurship and Innovation (PDF), the 308-page report argues that many large businesses are closing in-house research facilities and instead buying in new expertise and technologies by acquiring hi-tech start-ups.

Climate Change

Commodity Investors Brace for El Niño

Commodities investors are bracing themselves for the ever-growing possibility for the occurrence of a weather phenomenon known as El Niño by mid-year which threatens to play havoc with commodities markets ranging from cocoa to zinc.

The El Niño phenomenon, which tends to occur every 3-6 years, is associated with above-average water temperatures in the central and eastern Pacific and can, in its worst form, bring drought to West Africa (the world’s largest cocoa producing region), less rainfall to India during its vital Monsoon season and drier conditions for the cultivation of crops in Australia.

Economics

Researchers Tested The ‘Gambler’s Fallacy’ On Real-Life Gamblers And Stumbled Upon An Amazing Realization I love this stuff. I always think of my poker group.

..gamblers appear to be behaving as though they believe in the gambler’s fallacy, that winning or losing a bunch of bets in a row means that the next bet is more likely to go the other way. Their reactions to that belief — with winners taking safer bets under the assumption they’re going to lose and losers taking long-shot bets believing their luck is about to change — lead to the opposite effect of making the streaks longer

Foreign Affairs Focus on Books: Thomas Piketty on Economic Inequality


Is the U.S. Shale Boom Going Bust?

Among drilling critics and the press, contentious talk of a “shale bubble” and the threat of a sudden collapse of America’s oil and gas boom have been percolating for some time. While the most dire of these warnings are probably overstated, a host of geological and economic realities increasingly suggest that the party might not last as long as most Americans think.

Apes Can Definitely Use Tools

Bonobo Or Boy Scout? Great Ape Lights Fire, Roasts Marshmallows


 

Forecasting – Climate Change and Infrastructure

You really have to become something like a social philosopher to enter the climate change and infrastructure discussion. I mean this several ways.

Of course, there is first the continuing issue of whether or not climate change is real, or is currently being reversed by a “pause” due to the oceans or changes in trade winds absorbing some of the increase in temperatures. So for purposes of discussion, I’m going to assume that climate change is real, and with a new El Niño this year global temperatures and a whole panoply of related weather phenomena – like major hurricanes – will come back in spades.

But then can we do anything about it? Is it possible for a developed or “mature” society to plan for an uncertain, but increasingly likely future? With this question come visions of the amazingly dysfunctional US Congress, mordantly satirized in the US TV show House of Cards.

The National Society of Professional Engineers points out that major infrastructure bills relating to funding the US highway system and water systems are coming up in Congress in 2014.

Desperately needed long-term infrastructure projects were deferred to address other national priorities or simply fell victim to the ongoing budget crisis. In fact, federal lawmakers extended the surface transportation authorization an unprecedented 10 times between 2005 and 2012, when Congress finally authorized the two-year Moving Ahead for Progress in the 21st Century Act (MAP-21). Now, with MAP-21 set to expire before the end of 2014, two of the most significant pieces of infrastructure legislation are taking center stage in Congress. The Water Resources Reform and Development Act (WRRDA) and the reauthorization of the surface transportation bill present a rare opportunity for Congress to set long-term priorities and provide needed investment in our nation’s infrastructure. Collectively, these two bills cover much, though not all, of US infrastructure. The question then becomes, can Congress overcome continuing partisan gridlock and a decades-long pattern of short-term fixes to make a meaningful commitment to the long-term needs of US infrastructure?

Yes, for sure, that is the question.

Hurricane Sandy – really by the time it hit New Jersey and New York a fierce tropical storm – wreaked havoc on Far Rockaway, flooding the New York City subway system in 2012. This gave rise to talk of sea walls after the event.  And I assume something like that is in the planning stages on drawing boards somewhere on the East Coast. But the cost of “ten story tall pilings” on which would be hinged giant gates is on the order of billions of US dollars.

California

I notice interesting writing coming out of California, pertaining to the smart grid and the need to extend this concept from electricity to water.

The California Energy Commission (CEC) publishes an Integrated Energy Policy Report (IEPR – pronounced eye-per) every two years, and the 2013 IEPR was just approved ..Let’s look at two climate change impacts – temperature and precipitation.  From a temperature perspective, the IEPR anticipates that as the thermometer rises, so does the demand for electricity to run AC.  San Francisco Peninsula communities that never had a need for AC will install a couple million units to deal with summer temperatures formerly confined to the Central Valley.  PG&E and municipal utilities in Northern California will notice impacts in seasonal demand for electricity in both the duration of heat waves and peak apexes during the hottest times of day.  In the southern part of the state, the demand will also grow as AC units work harder to offset hotter days. At the same time, increased temperatures decrease power plant efficiencies, whether the plant generates electricity from natural gas, solar thermal, nuclear, or geothermal.  Their cooling processes are also negatively impacted by heat waves.  Increased temperatures also impact transmission lines – reducing their efficiency and creating line sags that can trigger service disruptions. Then there’s precipitation.  Governor Jerry Brown just announced a drought emergency for the state.  A significant portion of California’s water storage system relies on the Sierra Mountains snowpack, which is frighteningly low this winter.  This snowpack supplies most of the water sourced within the state, and hydropower derived from it supplies about 15% of the state’s homegrown electricity.  A hotter climate means snowfall becomes rainfall, and it is no longer freely stored as snow that obligingly melts as temperatures rise.  It may not be as reliably scheduled for generation of hydro power as snowfalls shift to rainfalls. We may also receive less precipitation as a result of climate change – that’s a big unknown right now.  One thing is certain.  A hotter climate will require more water for agriculture – a $45 billion economy in California – to sustain crops.  And whether it is water for industrial, commercial, agricultural, or residential uses, what doesn’t fall from the skies will require electricity to pump it, transport it, desalinate it, or treat it.

Boom – A Journal of California packs more punch in discussing the “worst case”

“The choice before us is not to stop climate change,” says Jonathan Parfrey, executive director of Climate Resolve in Los Angeles. “That ship has sailed. There’s no going back. There will be impacts. The choice that’s before humanity is how bad are we going to do it to ourselves?”

So what will it be? Do you want the good news or the bad news first?

The bad news. OK.

If we choose to do nothing, the nightmare scenario plays out something like this: amid prolonged drought conditions, wildfires continuously burn across a dust-dry landscape, while potable water has become such a precious commodity that watering plants is a luxury only residents of elite, gated communities can afford. Decimated by fires, the power grid infrastructure that once distributed electricity—towers and wires—now loom as ghostly relics stripped of function. Along the coast, sea level rise has decimated beachfront properties while flooding from frequent superstorms has transformed underground systems, such as Bay Area Rapid Transit (BART), into an unintended, unmanaged sewer system..

This article goes on to the “good news” which projects a wave of innovations and green technology by 2050 to 2075 in California.

Sea Level Rise

Noone knows, at this point, the extent of the rise in sea level in coming years, and interestingly, I never seen a climate change denier also, in the same breath, deny that sea levels have been rising historically.

There are interesting resources on sea level rise, although projections of how much rise over what period are uncertain, because no one knows whether a big ice mass, such as parts of the Antarctic ice shelf are going to melt on an accelerated schedule sometime soon.

An excellent scientific summary of the sea level situation historically can be found in Understanding global sea levels: past, present and future.

Here is an overall graph of Global Mean Sea Level –

GMSL

This inexorable trend has given rise to map resources which suggest coastal areas which would be underwater or adversely affected in the future by sea surges.

The New York Times’ interactive What Could Disappear suggests Boston might look like this, with a five foot rise in sea level expected by 2100

Boston

The problem, of course, is that globally populations are concentrated in coastal areas.

Also, storm surges are nonlinearly related to sea level. Thus, a one (1) foot rise in sea level could be linked with significantly more than 1 foot increases in the height of storm surges.

Longer Term Forecasts

Some years back, an interesting controversy arose over present value discounting in calculating impacts of climate change.

So, currently, the medium term forecasts of climate change impacts – sea level rises of maybe 1 to 2 feet, average temperature increases of one or two degrees, and so forth – seem roughly manageable. The problem always seems to come in the longer term – after 2100 for example in the recent National Academy of Sciences study funded, among others, by the US intelligence community.

The problem with calculating the impacts and significance of these longer term impacts today is that the present value accounting framework just makes things that far into the future almost insignificant.

Currently, for example, global output is on the order of 80 trillion dollars. Suppose we accept a discount rate of 4 percent. Then, calculating the discount factor 150 years from today, in 2154, we have 0 .003. So according to this logic, the loss of 80 trillion dollars worth of production in 2154 has a present value of about 250 billion dollars. Thus, losing an amount of output in 150 years equal to the total productive activity of the planet today is worth a mere 250 billion dollars in present value terms, or about the current GDP of Ireland.

Now I may have rounded and glossed some of the arithmetic possibly, but the point stands no matter how you make the computation.

This is totally absurd. Because as a guide to losing future output of $80 trillion dollars in a century and one half, it seems we should be willing to spend on a planetary basis more than a one-time cost of $35 per person today, when the per capita global output is on the order of $1000 per person.

So we need a better accounting framework.

Of course, there are counterarguments. For example, in 150 years, perhaps science will have discovered how to boost the carbon dioxide processing capabilities of plants, so we can have more pollution. And looking back 150 years to the era of the horse and buggy, we can see that there has been tremendous technological change.

But this is a little like waiting for the amazing “secret weapons” to be unveiled in a war you are losing.

Header photo courtesy of NASA

Predicting the Hurricane Season

I’ve been focusing recently on climate change and extreme weather events, such as hurricanes and tornados. This focus is interesting in its own right, offering significant challenges to data analysis and predictive analytics, and I also see strong parallels to economic forecasting.

The Florida State University Center for Ocean-Atmospheric Prediction Studies (COAPS) garnered good press 2009-2012, for its accurate calls on the number of hurricanes and named tropical storms in the North Atlantic. Last year was another story, however, and it’s interesting to explore why 2013 was so unusual – there being only two (2) hurricanes and no major hurricanes over the whole season.

Here’s the track record for COAPS, since it launched its new service.

Hurricaneforecastaccuracy

The forecast for 2013 was a major embarrassment, inasmuch as the Press Release at the beginning of June 2013 predicted an “above-average season.”

Tim LaRow, associate research scientist at COAPS, and his colleagues released their fifth annual Atlantic hurricane season forecast today. Hurricane season begins June 1 and runs through Nov. 30.

This year’s forecast calls for a 70 percent probability of 12 to 17 named storms with five to 10 of the storms developing into hurricanes. The mean forecast is 15 named storms, eight of them hurricanes, and an average accumulated cyclone energy (a measure of the strength and duration of storms accumulated during the season) of 135.

“The forecast mean numbers are identical to the observed 1995 to 2010 average named storms and hurricanes and reflect the ongoing period of heightened tropical activity in the North Atlantic,” LaRow said.

The COAPS forecast is slightly less than the official National Oceanic and Atmospheric Administration (NOAA) forecast that predicts a 70 percent probability of 13 to 20 named storms with seven to 11 of those developing into hurricanes this season…

What Happened?

Hurricane forecaster Gary Bell is quoted as saying,

“A combination of conditions acted to offset several climate patterns that historically have produced active hurricane seasons,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center, a division of the National Weather Service. “As a result, we did not see the large numbers of hurricanes that typically accompany these climate patterns.”

More informatively,

Forecasters say that three main features loom large for the inactivity: large areas of sinking air, frequent plumes of dry, dusty air coming off the Sahara Desert, and above-average wind shear. None of those features were part of their initial calculations in making seasonal projections. Researchers are now looking into whether they can be predicted in advance like other variables, such as El Niño and La Niña events.

I think it’s interesting NOAA stuck to its “above-normal season” forecast as late as August 2013, narrowing the numbers only a little. At the same time, neutral conditions with respect to la Nina and el Nino in the Pacific were acknowledged as influencing the forecasts. The upshot – the 2013 hurricane season in the North Atlantic was the 7th quietest in 70 years.

Risk Behaviors and Extreme Events

Apparently, it’s been more than 8 years since a category 3 hurricane hit the mainland of the US. This is chilling, inasmuch as Sandy, which caused near-record damage on the East Coast, was only a category 1 when it made landfall in New Jersey in 2012.

Many studies highlight a “ratchet pattern” in risk behaviors following extreme weather, such as a flood or hurricane. Initially, after the devastation, people engage in lots of protective, pre-emptive behavior. Typically, flood insurance coverage shoots up, only to gradually fall off, when further flooding has not been seen for a decade or more.

Similarly, after a volcanic eruption, in Indonesia, for example, and destruction of fields and villages by lava flows or ash – people take some time before they re-claim those areas. After long enough, these events can give rise to rich soils, supporting high crop yields. So since the volcano has not erupted for, say, decades or a century, people move back and build even more intensively than before.

This suggests parallels with economic crisis and its impacts, and measures taken to make sure “it never happens again.”

I also see parallels between weather and economic forecasting.

Maybe there is a chaotic element in economic dynamics, just as there almost assuredly is in weather phenomena.

Certainly, the curse of dimension in forecasting models translates well from weather to economic forecasting. Indeed, a major review of macroeconomic forecasting, especially of its ability to predict recessions, concludes that economic models are always “fighting the last war,” in the sense that new factors seem to emerge and take control during every major economic crises. Things do not repeat themselves exactly. So, if the “true” recession forecasting model has legitimately 100 drivers or explanatory variables, it takes a long historic record to sort out the separate influences of these – and the underlying technological basis of the economy is changing all the time.

Tornado Frequency Distribution

Data analysis, data science, and advanced statistics have an important role to play in climate science.

James Elsner’s blog Hurricane & Tornado Climate offers salient examples, in this regard.

Yesterday’s post was motivated by an Elsner suggestion that the time trend in maximum wind speeds of larger or more powerful hurricanes is strongly positive since weather satellite observations provide better measurement (post-1977).

Here’s a powerful, short video illustrating the importance of proper data segmentation and statistical characterization for tornado data – especially for years of tremendous devastation, such as 2011.

Events that year have a more than academic interest for me, incidentally, since my city of birth – Joplin, Missouri – suffered the effects of a immense supercell which touched down and destroyed everything in its path, including my childhood home. The path of this monster was, at points, nearly a mile wide, and it gouged out a track several miles through this medium size city.

Here is Elsner’s video integrating data analysis with matters of high human import.

There is a sort of extension, in my mind, of the rational expectations issue to impacts of climate change and extreme weather. The question is not exactly one people living in areas subject to these events might welcome. But it is highly relevant to data analysis and statistics.

The question simply is whether US property and other insurance companies are up-to-speed on the type of data segmentation and analysis that is needed to adequately capture the probable future impacts of some of these extreme weather events.

This may be where the rubber hits the road with respect to Bayesian techniques – popular with at least some prominent climate researchers, because they allow inclusion of earlier, less-well documented historical observations.

Quantile Regression

There’s a straight-forward way to understand the value and potential significance of quantile regression – consider the hurricane data referenced in James Elsner’s blog Hurricane & Tornado Climate.

Here is a plot of average windspeed of hurricanes in the Atlantic and Gulf Coast since satellite observations began after 1977.

HurricaneAvgWS

Based on averages, the linear trend line increases about 2 miles per hour over this approximately 30 year period.

An 80th percentile quantile regression trend line, on the other hand, with this data indicates that the trend in the more violent hurricanes shows an about 15 mph increase over this same period.

HurricaneQuartileReg

In other words, if we look at the hurricanes which are in the 80th percentile or more, there is a much stronger trend in maximum wind speeds, than in the average for all US-related hurricanes in this period.

A quantile q, 0<q<1, splits the data into proportions q below and 1-q above. The most familiar quantile, thus, may be the 50th percentile which is the quantile which splits the data at the median – 50 percent below and 50 percent above.

Quantile regression (QR) was developed, in its modern incarnation by Koenker and Basset in 1978. QR is less influenced by non-normal errors and outliers, and provides a richer characterization of the data.

Thus, QR encourages considering the impact of a covariate on the entire distribution of y, not just is conditional mean.

Roger Koenker and Kevin F. Hallock’s Quantile Regression in the Journal of Economic Perspectives 2001 is a standard reference.

We say that a student scores at the tth quantile of a standardized exam if he performs better than the proportion t of the reference group of students and worse than the proportion (1–t). Thus, half of students perform better than the median student and half perform worse. Similarly, the quartiles divide the population into four segments with equal proportions of the reference population in each segment. The quintiles divide the population into five parts; the deciles into ten parts. The quantiles, or percentiles, or occasionally fractiles, refer to the general case.

Just as we can define the sample mean as the solution to the problem of minimizing a sum of squared residuals, we can define the median as the solution to the problem of minimizing a sum of absolute residuals.

Ordinary least squares (OLS) regression minimizes the sum of squared errors of observations minus estimates. This minimization leads to explicit equations for regression parameters, given standard assumptions.

Quantile regression, on the other hand, minimizes weighted sums of absolute deviations of observations on a quantile minus estimates. This minimization problem is solved by the simplex method of linear programming, rather than differential calculus. The solution is robust to departures from normality of the error process and outliers.

Koenker’s webpage is a valuable resource with directions for available software to estimate QR. I utilized Mathworks Matlab for my estimate of a QR with the hurricane data, along with a supplemental program for quantreg(.) I downloaded from their site.

Here are a couple of short, helpful videos from Econometrics Academy.

Featured image from http://www.huffingtonpost.com/2012/10/29/hurricane-sandy-apps-storm-tracker-weather-channel-red-cross_n_2039433.html

Possibilities for Abrupt Climate Change

The National Research Council (NRC) published ABRUPT IMPACTS OF CLIMATE CHANGE recently, downloadable from the National Academies Press website.

It’s the third NRC report to focus on abrupt climate change, the first being published in 2002. NRC members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

The climate change issue is a profound problem in causal discovery and forecasting, to say the very least.

Before I highlight graphic and pictoral resources of the recent NRC report, let me note that Menzie Chin at Econbrowser posted recently on Economic Implications of Anthropogenic Climate Change and Extreme Weather. Chin focuses on the scientific consensus, presenting graphics illustrating the more or less relentless upward march of global average temperatures and estimates (by James Stock no less) of the man-made (anthropogenic) component.

The Econbrowser Comments section is usually interesting and revealing, and this time is no exception. Comments range from “climate change is a left-wing conspiracy” and arguments that “warmer would be better” to the more defensible thought that coming to grips with global climate change would probably mean restructuring our economic setup, its incentives, and so forth.

But I do think the main aspects of the climate change problem – is it real, what are its impacts, what can be done – are amenable to causal analysis at fairly deep levels.

To dispel ideological nonsense, current trends in energy use – growing globally at about 2 percent per annum over a long period – lead to the Earth becoming a small star within two thousand years, or less – generating the amount of energy radiated by the Sun. Of course, changes in energy use trends can be expected before then, when for example the average ambient temperature reaches the boiling point of water, and so forth. These types of calculations also can be made realistically about the proliferation of the automobile culture globally with respect to air pollution and, again, contributions to average temperature. Or one might simply consider the increase in the use of materials and energy for a global population of ten billion, up from today’s number of about 7 billion.

Highlights of the Recent NRC Report

It’s worth quoting the opening paragraph of the report summary –

Levels of carbon dioxide and other greenhouse gases in Earth’s atmosphere are exceeding levels recorded in the past millions of years, and thus climate is being forced beyond the range of the recent geological era. Lacking concerted action by the world’s nations, it is clear that the future climate will be warmer, sea levels will rise, global rainfall patterns will change, and ecosystems will be altered.

So because of growing CO2 (and other greenhouse gases), climate change is underway.

The question considered in ABRUPT IMPACTS OF CLIMATE CHANGE (AICH), however, is whether various thresholds will be crossed, whereby rapid, relatively discontinuous climate change occurs. Such abrupt changes – with radical shifts occurring over decades, rather than centuries – before. AICH thus cites,

..the end of the Younger Dryas, a period of cold climatic conditions and drought in the north that occurred about 12,000 years ago. Following a millennium-long cold period, the Younger Dryas abruptly terminated in a few decades or less and is associated with the extinction of 72 percent of the large-bodied mammals in North America.

The main abrupt climate change noted in AICH is rapid decline of the Artic sea ice. AICH puts up a chart which is one of the clearest examples of a trend you can pull from environmental science, I would think.

ArticSeaIce

AICH also puts species extinction front and center as a near-term and certain discontinuous effect of current trends.

Apart from melting of the Artic sea ice and species extinction, AICH lists destabilization of the Antarctic ice sheet as a nearer term possibility with dramatic consequences. Because a lot of this ice in the Antarctic is underwater, apparently, it is more at risk than, say, the Greenland ice sheet. Melting of either one (or both) of these ice sheets would raise sea levels tens of meters – an estimated 60 meters with melting of both.

Two other possibilities mentioned in previous NRC reports on abrupt climate change are discussed and evaluated as low probability developments until after 2100. These are stopping of the ocean currents that circulate water in the Atlantic, warming northern Europe, and release of methane from permafrost or deep ocean deposits.

The AMOC is the ocean circulation pattern that involves the northward flow of warm near-surface waters into the northern North Atlantic and Nordic Seas, and the south- ward flow at depth of the cold dense waters formed in those high latitude regions. This circulation pattern plays a critical role in the global transport of oceanic heat, salt, and carbon. Paleoclimate evidence of temperature and other changes recorded in North Atlantic Ocean sediments, Greenland ice cores and other archives suggest that the AMOC abruptly shut down and restarted in the past—possibly triggered by large pulses of glacial meltwater or gradual meltwater supplies crossing a threshold—raising questions about the potential for abrupt change in the future.

Despite these concerns, recent climate and Earth system model simulations indicate that the AMOC is currently stable in the face of likely perturbations, and that an abrupt change will not occur in this century. This is a robust result across many different models, and one that eases some of the concerns about future climate change.

With respect to the methane deposits in Siberia and elsewhere,

Large amounts of carbon are stored at high latitudes in potentially labile reservoirs such as permafrost soils and methane-containing ices called methane hydrate or clathrate, especially offshore in ocean marginal sediments. Owing to their sheer size, these carbon stocks have the potential to massively affect Earth’s climate should they somehow be released to the atmosphere. An abrupt release of methane is particularly worrisome because methane is many times more potent than carbon dioxide as a greenhouse gas over short time scales. Furthermore, methane is oxidized to carbon dioxide in the atmosphere, representing another carbon dioxide pathway from the biosphere to the atmosphere.

According to current scientific understanding, Arctic carbon stores are poised to play a significant amplifying role in the century-scale buildup of carbon dioxide and methane in the atmosphere, but are unlikely to do so abruptly, i.e., on a timescale of one or a few decades. Although comforting, this conclusion is based on immature science and sparse monitoring capabilities. Basic research is required to assess the long-term stability of currently frozen Arctic and sub-Arctic soil stocks, and of the possibility of increasing the release of methane gas bubbles from currently frozen marine and terrestrial sediments, as temperatures rise.

So some bad news and, I suppose, good news – more time to address what would certainly be completely catastrophic to the global economy and world population.

AICH has some neat graphics and pictoral exhibits.

For example, Miami Florida will be largely underwater within a few decades, according to many standard forecasts of increases in sea level (click to enlarge).

Florida

But perhaps most chilling of all (actually not a good metaphor here but you know what I mean) is a graphic I have not seen before, but which dovetails with my initial comments and observations of physicists.

This chart toward the end of the AICH report projects increase in global temperature beyond any past historic level (or prehistoric, for that matter) by the end of the century.

TempRise

So, for sure, there will be species extinction in the near term, hopefully not including the human species just yet.

Economic Impacts

In closing, I do think the primary obstacle to a sober evaluation of climate change involves social and economic implications. The climate change deniers may be right – acknowledging and adequately planning for responses to climate change would involve significant changes in social control and probably economic organization.

Of course, the AICH adopts a more moderate perspective – let’s be sure and set up monitoring of all this, so we can be prepared.

Hopefully, that will happen to some degree.

But adopting a more pro-active stance seems unlikely, at least in the near term. There is a wholesale rush to bringing one to several trillion persons who are basically living in huts with dirt floors into “the modern world.” Their children are traveling to cities, where they will earn much higher incomes, probably, and send money back home. The urge to have a family is almost universal, almost a concomitant of healthy love of a man and a woman. Tradeoffs between economic growth and environmental quality are a tough sell, when there are millions of new consumers and workers to be incorporated into the global supply chain. The developed nations – where energy and pollution output ratios are much better – are not persuasive when they suggest a developing giant like India or China should tow the line, limit energy consumption, throttle back economic growth in order to have a cooler future for the planet. You already got yours Jack, and now you want to cut back? What about mine? As standards of living degrade in the developed world with slower growth there, and as the wealthy grab more power in the situation, garnering even more relative wealth, the political dialogue gets stuck, when it comes to making changes for the good of all.

I could continue, and probably will sometime, but it seems to me that from a longer term forecasting perspective darker scenarios could well be considered. I’m sure we will see quite a few of these. One of the primary ones would be a kind of devolution of the global economy – the sort of thing one might expect if air travel were less possible because of, say, a major uptick in volcanism, or huge droughts took hold in parts of Asia.

Again and again, I come back to the personal thought of local self-reliance. There has been a growth with global supply chains and various centralizations, mergers, and so forth toward de-skilling populations, pushing them into meaningless service sector jobs (fast food), and losing old knowledge about, say, canning fruits and vegetables, or simply growing your own food. This sort of thing has always been a sort of quirky alternative to life in the fast lane. But inasmuch as life in the fast lane involves too much energy use for too many people to pursue, I think decentralized alternatives for lifestyle deserve a serious second look.

Polar bear on ice flow at top from http://metro.co.uk/2010/03/03/polar-bears-cling-to-iceberg-as-climate-change-ruins-their-day-141656/

Climate Gotterdammerung

For video fans, here are three videos on climate change and global warming. Be sure and see the third – it’s very dramatic.

White House smacks down climate deniers in new video

“If you’ve been hearing that extreme cold spells like the one that we’re having in the United States now disprove global warming, don’t believe it,” Holdren [White House Science Advisor] says in the video, before launching into a succinct explanation of how uneven global temperature changes are destabilizing the polar vortex and making it “wavier.”

“The waviness means that there can be increased, larger excursions of wintertime cold air southward,” Holdren says. He adds that “increased excursions of relatively warmer” air can also move into the “far north” as the globe warms.

NASA Graphic Shows Six Terrifying Decades Of Global Warming (VIDEO)

Largest Glacier Calving Ever Filmed

This is from “Chasing Ice.” James Balog, the National Geographic photographer, speaks at the end of the film, and his assistants, are staked out on a high ridge above all this and took the videos.

Some of shards of ice are three times taller than the skyscrapers in Lower Manhattan – a comparable area to the breakup zone.