Forests and Global Warming, Part 1: A Global Warming Primer

In the last chapter I listed more than two dozen essential functions--ecosystem services--performed by forests.  Together they are so critical that without them, the planet would be unlivable for most species we recognize.  Separating out one as more important than the others is only theoretically possible, since forests are organic systems, with functions that intertwine with and influence one another.  It’s the same problem we would have explaining why our heart, or our lungs, or our brain mattered most.  They all work together, and without any one of them, none of them function. 

Nevertheless, a single one of those reasons forests matter is so vital that it needs a section of its own--three chapters, in fact.  I’m speaking of the last item on the list: forests’ storage of carbon and their role in global warming.  Readers who are familiar with global warming science and scenarios can skip or skim over this chapter if they wish.  For those who are less familiar with the science behind global warming, the already-detectable impacts of the warming, and projections for the warming’s longer-term affects, I’ll provide a summary of where things currently stand.  

Wallace Stegner once said that an author doesn’t finish a book; he relinquishes it. There are always things a writer wants to fiddle with, add to, strengthen, rethink, clarify.  At some point, however, one simply has to stop.  No chapters have been more difficult to relinquish than this one and the two that follow.  Every week, every day, some new research or new data further illuminates how rapidly global warming is affecting forests, oceans, grasslands, peatlands--every ecosystem on the planet,-- and I keep coming back to bring the material up to date, to do my part in sounding the alarm that would somehow waken us, as we sleep while fire races through our home. 

* * * *

Yesterevening, before supper, I stood out on our small front porch and looked eastward.  Rain and stiff winds this past week had stripped almost all of the remaining leaves from trees, and the hillside on the opposite side of the Rivanna was glowing with thousands of points of light--literally. It was a cheerful sight in the dying year, almost festive.  Twin rivers of light seemed to flow up and down the hill, red lights twinkling from brake lights blinking and taillights shining as a seemingly-endless line of commuters headed home, and white lights beaming from headlights as others headed into the city to work or dine.  The rivers ran from the new hospital and “office park” at the top to the shopping mall at the bottom of the hill, broadened by all the car lots and other businesses lining the lanes between them.

Thomas Jefferson named the mountain I was watching.  He called it “Pantops,” from two Greek words meaning “all seeing.”  He loved the vista from the mountain--the Blue Ridge mountains against the skyline, the fields and forests sprawling everywhere before him, garbed in green.  Today, the Charlottesville Area Association of Realtors shares his enthusiasm for Pantops.  Their website hails Pantops’ “Proud Past, Vibrant Future” with this description: 

“Today Pantops is one of the fastest-growing, most-desirable areas in Albemarle County to live and work. Its location is ideal, with easy access to I-64 and a short distance from the Downtown Mall and the University of Virginia. It has combined a variety of residential options—from apartments to townhomes to condos to single-family dwellings—with nearby shopping, restaurants, and businesses.” 

Yet a reality belying this cheerful boosterism is that every light, every meal, every firing piston of a car or truck, pours more carbon dioxide into the air we live in.  Likewise, the deforestation that cleared the way for those malls, office buildings, car dealerships, the new hospital, and all the rest of it also poured tons of CO₂  into the atmosphere.  Issues of habitat destruction aside, the bustle of human activity the realtors were praising comes with major profits for some--but an enormous cost for us all.

The science of global warming has been accumulating quickly.  It’s unfortunate that politics rather than science has come to dominate debate in the U.S., and I certainly don’t want to get mired in partisan bickering.  But I can’t turn away from the topic either, and for those who grow belligerent at any discussion that validates the reality of modern global warming and humans’ responsibility for it, there is little one can do to avoid giving offense.  I have tried, as best I can, to determine what seems to be true,  and to report it without slapping someone in the face with it. 

For more detailed analyses, I would recommend Tim Flannery’s The Weather Makers: How Man Is Changing the Climate and What It Means for Life on Earth (2005), a persuasive work that is beautifully written, wide-ranging, insightful and authoritative. Bill McKibben’s The End of Nature was a starting point for popular awareness of global warming.  Although it originally sounded the alarm back in 1989 (and was reissued in 2006 with a new introduction), it is still among the clearest, most readable, and most compelling introductions to global warming--although I wish he had chosen a more accurate title.   Michael Mann’s The Hockey Stick and the Climate Wars: Dispatches from the Front Lines (2012) provides a brief but incisive review of climate science and follows that with a thorough and personal account of the lies and tactics used by well-funded climate change deniers to discredit climate science in general and his own work in particular.  There are enough other well-researched books on global warming and climate change to fill a small library.  

Let’s begin by addressing three basic issues on which too many U.S. citizens seem unclear.

A Global Warming Primer

Question #1     Why do some people refer to ‘climate change’ rather than ‘global warming’?  Is this shift in language a tacit admission that ‘global warming’ is not really taking place?  Is one term correct and the other wrong?

The use of the two terms doesn’t mean that one is wrong or has been replaced.  Both are used because they refer to two different but related things.  ”Global warming” refers to the average increase in temperatures for Earth’s land surface, water, and lower atmosphere.  It’s a generalized whole-world snapshot.  “Climate change” is specific and localized.  It refers to all the ways localities and regions react to global warming.  Those include changes in wind patterns, temperature ranges, the distribution and intensity of rain and snow, the movement of ocean currents, the length of growing seasons, and a host of other factors. 

Since global warming is an average, it obviously makes sense that on this vast, sprawling planet of ours, many places are now warmer much of the time than they have been.  A much smaller number of places may actually be cooler.  And even warmer places may experience cold snaps and heavy snows.  Heavier rains and snows, in fact, are consistent with global warming theory and computer models, because a warmer atmosphere causes more evaporation and can carry more moisture.

Question #2    Is global warming, as defined above, actually taking place?  Is Earth really warming?

The answer is an unqualified “yes.”  An overwhelming body of evidence indicates that our planet is heating up, and that the rate of warming is accelerating.  Because of normal variability and complexity, the best evidence is long-term, wide-scale data that displays trends and allows the calculation of probabilities.  Here is a sample of the variety of evidence available:

• Planet-wide temperature records going back 150 years.  The past 10 years have been the warmest decade on record for the planet; the year just ended [2012] was the warmest on record for the contiguous U.S., and an ominous 3.2ºF above the average temperature for the 20th century.  This data is corroborated by other methods, some of the most important being listed below.  To reach farther into the past, scientists use so called “proxy data”--other kinds of evidence of what climate was like, some of them reaching far into our planetary past.  Proxy data includes such things as tree rings; isotope geochemistry, which can garner information from ice cores drawn from glaciers and ice sheets frozen for millennia, as well from sediments drawn from ancient lake and ocean beds; pollens preserved in amber and sediments; fossils; microplankton; marine shells and sea level terraces; and historical documents.  

• Sea surface temperature monitoring records.  The world’s ocean surface temperature in June 2009 was the warmest ever recorded.  Sea surface temperatures are derived from both satellites using remote-sensing technology and from ship-board measurements reaching back to 1854.

• Ocean salinity profiles.  Records from fifty years of sea surface salinity monitoring show a significant impact of climate change on the global water cycle, with wet regions getting wetter and dry regions getting drier.  This redistribution of rainfall will have a profound effect on agriculture and food supplies, and cause significant alterations in ecosystems. 

• Arctic ice cap measurements.  The cap is at the lowest level ever recorded, and is in a “death spiral” because of rising temperatures.  It is now expected that within the next 20 years, the North Pole will be ice-free in summer for the first time in a million years.  (In Antarctica, by contrast, climate models are showing that higher evaporation levels and changing patterns of atmospheric circulation will result in more snow falling on the ice pack, leading to an expanding ice area there.  

• Glacier measurements.  Glaciers are melting on six continents (Australia has no glaciers), and the melting is accelerating.

• Rainfall records.  Average annual rainfall for Earth has increased by up to 10% during the past 100 years because warming increases evaporation and transpiration.  There has also been a measurable increase -- 2% to 4% -- in the frequency of heavy precipitation.

• Sea level measurements.  As a global average, sea level has risen by 10 to 20 cm during the past 100 years.  

• Measurements of ocean acidity.  The ocean is becoming more acidic as it absorbs excess CO₂ from the atmosphere.  That process has been ongoing since the start of the Industrial Revolution, around 1750.  At this point the ocean is taking in about 2 billion tons of CO₂ per year, and its acidity has increased a whopping 30%.  

• Surveys of coral reefs.  More than 25% of the world’s coral reefs have been destroyed by global warming and pollution--with a 90% mortality rate in the Indian and Pacific Oceans.  Most of the loss is attributed to global warming.

• Ice cores taken from the Dunde Ice Cap on the Qinghai-Tibetan Plateau.  These cores indicate that the years since 1938 have been the warmest in the last 12,000 years.

• Lake and river ice records.  Over the past 100 years, there has been a reduction of two weeks in the annual duration of lake and river ice.

• Plant and animal migrations.  Numerous studies show trees, other plants, birds, fish, insects, and every kind of living thing imaginable moving from their historic ranges into new territories.  References to a variety of specific studies documenting these shifts appear throughout this book. 

• Computer modeling.  Global warming computer models have reflected the real-world impact of humans on global temperature (via the burning of fossil fuels, deforestation, industrial pollution, etc.) with significant and steadily-improving accuracy.  

• A scientific consensus, Part I.  Assessment reports by the Intergovernmental Panel on Climate Change--usually referred to simply as the IPCC--have been published periodically, representing the consensus of the world’s scientists on the risks of anthropogenic (human-caused) climate change.  The IPCC was founded by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), and later endorsed by the United Nations General Assembly.  Its broad representation--many thousands of scientists and experts who receive no pay from the UN and meet, assess, and debate climate change issues over a number of years--makes it the internationally accepted authority on  climate change.  The process seems as fair, collaborative, and authoritative as one could hope for, given the mix of interests among the many governments.  

To date there have been four IPCC assessment reports, in 1990, 1995, 2001, and 2007.  The fifth is scheduled to be delivered in 2014.  No report is released without going through a rigorous and systematic vetting, and without representing a consensus of the leading climate researchers and the participating governments.   

• A scientific consensus, Part II.  Back in 2004, Naomi Oreskes, a history of science professor at the University of California - San Diego, reviewed 928 abstracts of peer-reviewed scientific publications dealing with global climate change with the intent of discovering whether reports issued by the IPCC, the National Academy of Sciences, and the American Association for the Advancement of Science were bypassing legitimate academic dissent on climate change.  She found no evidence that was the case: Not a single paper disputed that our current global warming is due to human activity. 

• A scientific consensus, Part III.  In a 2009 survey of scientists, 97 percent of climatologists surveyed said that global warming is taking place and is caused by human activity.  As your own experience probably shows you, it’s a rarity indeed when 97% of a group agrees on anything.  Yet the people who know climate best, who study it on an ongoing basis, and whose professional careers are focused on climate issues and dynamics, agree almost unanimously that anthropogenic global warming is real and measurable.  

Having these conclusions endorsed by 97% of climatologists should certainly give climate-change skeptics pause.  The conversion of one of the most prominent skeptics should be even more cause for sober rethinking.

  I’m referring to the work of Prof. Richard Muller, a physicist at the University of California who established the Berkeley Earth Surface Temperature Project (with the catchy acronym “BEST”) to re-examine global temperature data from numerous sources.  Muller, a vocal climate change skeptic, received major funding from corporate energy and conservative sources, including the Charles G. Koch Charitable Foundation.  The underlying assumption of his work was that previous studies--which  had documented the rise in global warming attributable to human behavior--were biased by human decisions in the course of analysis.   Muller’s team set out to eliminate that presumed “climate-change-believer” bias by completely automating the statistical analysis.

To Muller’s surprise, and to the consternation of his backers, the BEST team found that their results mirrored those of previous studies--only with a greater degree of certainty!   "Our results show that the average temperature of the Earth's land has risen by 2.5℉ over the past 250 years, including an increase of 1.5 degrees over the most recent 50 years. Moreover, it appears likely that essentially all of this increase results from the human emission of greenhouse gases," he wrote in the New York Times.  “We were not expecting this, but as scientists, it is our duty to let the evidence change our minds."  Professor Muller deserves enormous credit for his pursuit of truth, his professional honesty, and ultimately his courage as well.

• Alarmed insurers and bankers.  These people aren’t scientists.  But within their own field they maintain detailed, voluminous stores of data and perform sophisticated analyses to analyze risk.  Profit and loss are apolitical; when it comes to corporate profits, liberal or conservative political correctness gives way to reality.  

Insurers have long-term records of payouts.  As increasingly frequent and historic weather-related disasters drive up damages and payouts, the insurers have drawn their own conclusions about climate change.  Franklin Nutter, president of the Reinsurance Association of America, says, “From our industry’s perspective, the footprints of climate change are around us and the trend of increasing damage to property and threat to lives is clear.”   World Bank President Jim Yong Kim, in November of 2012, warned that lagging efforts on “countries' current emission pledges and commitments under the UN Framework Convention on Climate Change would most likely result in 3.5-4°C warming,” and the bank issued an alarming report detailing global devastation--especially in developing nations--if the predicted warming actually occurs.  

• Among the government agencies documenting, monitoring and reporting on global warming are the U.S. Department of Energy, the National Oceanic and Atmospheric Administration (an agency within the Department of Commerce), and the U.S. Forest Service.

The kinds of evidence just listed, as well as numerous other types, demonstrate conclusively that global warming is real, human-caused, and accelerating at an alarming rate.  Among those who acknowledge this reality, as we have seen, are climatologists, oceanographers, biologists, bankers and insurers, and agencies of our own government.  To put it flatly, among the people with the best data and the most objective analyses, there is an overwhelming consensus that human-generated warming is an enormous threat to life as we know it on our planet.

Question #3    How do we know the warming is caused by human activity?  Aren’t there natural cycles that could account for the warming?

Three natural phenomena cause short-term variations in global temperatures: variations in solar radiation, volcanic aerosols, and El Niño-Southern Oscillation.

Methods for distinguishing the impact of human-caused warming from that of warming due to natural cycles has become more and more sophisticated.  There is no longer any scientific doubt that the accelerating warming we are seeing over the last forty years is overwhelmingly human-induced.  Here are the kinds of evidence, as reported by the Union of Concerned Scientists and other sources:

1)  Damon Matthews at Concordia University in Montreal and his colleagues have demonstrated that there is a simple and direct linear relationship between CO₂ emissions and an increase in global temperature, with each metric ton of CO₂ emissions raising global temperature 0.0000000000015 degrees.  

2)  Scientists are able to tell how much of the CO₂ in the atmosphere comes from burning fossil fuels and from deforestation by means of isotopic signatures.  Carbon-14 is carbon created out in the atmosphere; low isotope carbon-14 (the type of carbon in fossil fuels) is lighter because it was formed underground, unexposed to the atmosphere.  Thus it is possible to tell where the different molecules in the atmosphere originated.  Increases in the volume of “lighter” CO₂ molecules track very closely with known human increases in those emissions. 

3)  Computerized climate models designed to predict temperature changes have been unable to recreate what is actually happening when they use only natural climate drivers.  When they are programmed with human-caused conditions factored in--things such as industrial emissions and land use changes--the models closely mirror the warming that is taking place in the atmosphere and in the ocean.  In other words, the “natural causes” hypothesis fails the most basic test of science: it does not predict actual recorded changes.  The “human causes” hypothesis passes the test, and as more and more factors contributing to the warming are discovered--things which were unknown only five years ago--predictions incorporating human causes reach a higher and higher level of accuracy.  They match real-world observations.  In short: one explanation fits the facts; the other does not.

4)  Carbon dioxide and other greenhouse gases are accumulating in the troposphere--the lower layer of the atmosphere--and pushing the boundary between it and the stratosphere--the upper layer of the atmosphere, which seems to be cooling--ever higher.  If the sun were the major factor in warming, both layers would be heating and the boundary would not be shifting so significantly. 

5)  The burden of proof is now on those claiming that natural causes are driving this historic rise in planetary temperatures and the drastic changes accompanying it.  To date no one has been able to present a plausible natural mechanism that explains what is happening.  When we factor in human activity, we have an explanation that works.

As Bill McKibben has pointed out, the critical basic facts with which to begin are these:  Since 1900, the average global temperature has risen about 1℉; during that same period, the amount of CO₂ in the atmosphere has increased about 30%, and is now at its highest level in 650,000 years.  The CO₂ figure continues to soar.  Atmospheric CO₂ levels have been monitored at Mauna Loa Observatory continuously since March of 1958, when it stood at 315.71 ppm (parts per million).  As of August 2012, atmospheric CO₂ stood at 392.41--nearly 400 ppm.  Back in May it had reached more than 396 ppm, but the global economic slowdown, which has led to a drop in industrial production and product transport; and higher fuel prices, which have led to less optional driving, have together resulted in a small reduction.

A one degree rise in average global temperature may not sound like much.  One degree?  Why worry?  It seems such a minor, insignificant change.  If we adjust the thermostat a single degree in our home’s heating or cooling system, we might not even notice a difference.  But this is one of those occasions where our reliance on the familiar is dangerous.  Comparisons between a degree in our homes and a degree in our planetary home are fatally flawed.  

  That’s because Earth is much more sensitive to temperature shifts than one might have expected.  A one degree upward shift in average global temperature represents an enormous charge of energy poured into a vast system.  Weather Underground’s Jeff Masters compares it to steroids for the atmosphere.  

When it comes to forests, that one degree of warming has already changed them in numerous ways. This is what is happening around us now--not conjecture, not extrapolation, not hyperbole, but simply facts.  A single degree of warming has amped up the scale and intensity of droughts and fires.  It has unleashed population explosions of destructive insects.  It has slowed tree growth in some places and increased it in others.  It has led to tree deaths over wide areas. It has sent trees moving to higher latitudes and altitudes.  

It’s not just forests that have felt the consequences, of course.  We don’t see many of the changes, and reporting on climate items is sporadic at best, so here might be a good point to pull together snapshots of some of the other major changes that are taking place.  Many of these are elaborations of issues alluded to in the earlier listing of the kinds of evidence available for global warming.

The one degree rise has accelerated the melting of many glaciers worldwide, cleared numerous mountaintops of snow, dramatically reduced Arctic sea ice, lengthened growing seasons, caused salinity shifts in the ocean and strengthened the water cycle by 4% between 1950 and 2000, warmed the ocean’s surface around 0.4ºC and raised its acidity greatly beyond natural levels, raised sea levels (currently lifting 3.2 mm per year on the East Coast of the U.S.), contributed to the global decline and deaths of reef-building corals and the countless organisms that inhabit them, changed bird migration patterns, wreaked havoc on amphibians, changed wind patterns and speeds, and contributed to an expansion of the boundaries of the tropics in the northern hemisphere by 0.7 degrees latitude per decade. 

Ocean reefs, beset by ocean acidification and warming waters (and with the added insult of pollution) are in serious decline, with anywhere from 50% to 85% of the reefs killed in many locations worldwide over the past fifty years.  Those reefs are the great gardens of the seas, with millions of people dependent on them for food or to make their living.  The reefs also protect coastlines from the brunt of storm surges by acting as breakwaters.  The loss of reefs will have a devastating effect on the ocean food chain, world food supplies, human economies, and coastal safety and stability. 

Just this month [September, 2012], the National Oceanic and Atmospheric Administration (commonly known as NOAA) reported that Arctic sea ice in August lost an average of 35,400 square miles of ice per day--the fastest rate ever recorded--, and shrank to the smallest extent ever recorded.  They also noted that the average land surface temperature for the planet, for the months of June, July, and August, was the hottest--here we go again--ever recorded.  

Yesterday, in the late afternoon, I stood on the Free Bridge and watched the sun glinting on the surface of the Rivanna.  The channel is broad there, and the water was low enough that I could easily have waded across.  The trip might have been surprisingly comfortable.  For even with a hint of chill in the breeze in these early days of fall, the shallow water was heating up.  The Rivanna and its tributaries--including Meadow Creek, Moore’s Creek, and Schenk’s Branch, all within walking distance of my home--are part of the Chesapeake Bay watershed, which in turn makes up part of the Northeast Shelf Large Marine Ecosystem.  NOAA, the National Oceanic and Atmospheric Administration, just issued an “ecosystem advisory” for our ecosystem, based on pervasive high temperatures at both the sea’s surface and on the bottom as well.  The temperatures were the highest ever recorded, and sprawled over the entire ecosystem.  

Moore's Creek

The warming was especially intense in the Chesapeake and Delaware Bays, they reported, with surface temperatures climbing to more than 11℉ above the historical average, and bottom temperatures more than 9℉.  This warming is part of an alarming long-term trend.  

One consequence of this continued warming?  A 2009 study found that nearly half of 36 fish species studied--including some of those of most important to commercial fishing--have shifted their range northward and further offshore for the last four decades.  

A second likely consequence?  Smaller fish.  University of British Columbia have calculated that average fish size is likely to shrink because warmer water holds less oxygen fish can metabolize, at the same time fish will need more oxygen to go about their daily living.  Their projections are dire--an average reduction of 14 to 25% of body weight globally by 2050.  Rising ocean temperatures have already shrunk the size of haddock in the North Sea.  A sharply reduced seafood supply in a world with a rapidly growing population is yet another grim prospect in our warming world. 

Farther from home, huge changes are taking place in the cryosphere--those parts of the globe where water is frozen, including ice caps, ice sheets, glaciers, sea ice, icebergs, permafrost (perennially frozen ground), and seasonally frozen ground.  A single glacier--the Pine Island Glacier in West Antarctica--is made of of enough frozen water to almost double the ”best estimate” by the Intergovernmental Panel on Climate Change (usually referred to as the IPCC) of sea level rise in the 21st century.  The glacier, which is twice the size of Scotland, is remote and inaccessible, and only recently have scientists discovered via satellite instruments that the main part of the glacier is melting rapidly, and will likely have “disappeared,” as they put it, within a hundred years.  

In a July 2012 Scientific American article, Douglas Fox reported that the average speed of winds blowing off Antarctica’s coast has sped up 10% to 15% in the last three decades, resulting in billions of tons of snow being lifted from the surface and blown into the sea to melt.  At the same time, the collapse of Antarctica's ice shelves is being followed by a startling accelerated flow of the glaciers, which previously had been slowed by the ice shelves.  Of the 12 major ice shelves around the Antarctic, 7 are clearly melting or have already gone.  So much of Antarctica's ice load has disappeared that Earth’s crust--relieved of the burden--has bobbed up. 

None of these changes--the vast wind scouring, the rapidly collapsing ice shelves, nor the accelerated glacier flow--were factored into the IPCC’s 2007 report, which had predicted a sea level rise of 18 to 59 centimeters (7 inches to 23.23 inches) by the end of our current century.  Scientists are saying the increase could be twice or three times the IPCC projections.  It is now clear that, far from being alarmist, the last IPCC report seriously underestimated the rate the planet is heating up, and the consequences of the resulting climate changes.

Fox cites an analysis by Martin Vermeer of the Helsinki University of Technology which projects the most likely sea level rise, based on updated information, to be in the 75 to 190 centimeter range (29.5 inches to 74.8 inches).     Research by scientists from the Potsdam Institute for Climate Impact Research, Tempo Analytics and Laboratoire d'Etudes en Géophysique et Océanographie Spatiales, published even more recently [November, 2012], says that sea levels are rising at a rate 60% higher than that projected by the IPCC.  They are actually rising 3.2 mm per year, say the researchers, rather than than the 2 mm per year best estimate given in the 2007 IPCC report.  

What kind of impact will that kind of sea rise have?  Obviously, it will vary from location to location, but a study launched by the San Francisco Bay Conservation and Development Commission, projecting the ramifications of a 16” rise by 2050 and a 55” rise by 2100, gives us some sense of just how major the changes are likely to be.  They foresee:  the flooding or erosion of traditional coastline habitats; flooding of 93% of the current San Francisco and Oakland airports; loss of 87% of the public waterfront; salinization of fresh water sources; local extinction of some species; and the threat of 128 square miles of housing washed away!  

It’s too easy to write of something like 128 square miles of housing washed away, in a single piece of coastline, and let statistics numb any sense of the pain and loss that will cause.  

When our children were very young, my wife and I bought a huge old nine-room brick house in a racially-changing neighborhood; it was priced at $3,500, and listed as a “Handyman’s Special.”  Over the next couple of years, my friend Wally Giffen and I rewired it completely, to the code standard for new construction.  With the help of other friends, I redid much of the plumbing, installed showers in the bathroom, and replaced a portion of the roof.  I took out a wall to enlarge the living room, and sanded and refinished the floors.  I also spackled the plaster walls, painted every room, re-puttied windows, and replaced linoleum floor coverings with tile.  That was all done while working full time and helping parent three children.  It was a cooperative effort that meant so much to my wife and I, and everyone else who took part.  The house was transformed, but completing the jobs took hundreds and hundreds of hours.  And that was a single home.  

Trying to translate my own experience into all the care and effort that went into homes sprawled over 128 square miles gives me at least a feeling for what losing a home to encroaching sea waters would feel like, and how much anguish that 128 square miles would actually represent.  Every one of those lost homes is a storehouse of unreplaceable experiences.  If you didn’t build or rehab your own home, you still know how you struggled to finance it, furnish it, and improve it.  It wasn’t just assembled building materials, but work, memories, dreams, an important portion of the fabric of your life... washed away.

Analyses of sea level risings in the past are not comforting.  A University of Arizona study comparing melting ice sheets during the Last Interglacial Period (130,000 to 120,000 years ago) found that even small amounts of warming contribute to extensive ice sheet melting, They also point to a series of time lags: polar ice sheets lag behind ocean warming which lags behind the warming of the atmosphere.  What that means is that we are going to be seeing ice sheets melting for many years--and sea levels rising--even if we were to stop global warming tomorrow.  Their estimate is that we may already be facing a seal level rise in the range of 13.5 feet to 19 feet over several centuries!  (Note that Vermeer’s estimate was just to the end of this century.)  With so much of Earth’s human population concentrated in low-lying coastal areas, a rise anywhere in the ranges predicted by these studies will be catastrophic.  How you differentiate between catastrophic and really, really catastrophic becomes the question. 

A third study, by a cluster of scientists from the National Center for Atmospheric Research (NOAA again), the Center for Australian Weather and Climate Research, and Climate Central, concludes that even if aggressive efforts at cutting greenhouse gas emissions are taken--and prospects for that are looking dimmer and dimmer--sea levels will keep rising for several hundred years.  At best, with serious and extensive mitigation, the rise could be slowed.  

And a fourth study, headed by Michiel Schaeffer and published in Nature Climate Change, while cautious about the difficulties of long range predictions with so many uncertain elements in the equation, agrees with the previous study, and supplies estimates of the rise under different scenarios.  Schaeffer’s team warns that future changes already built into the system make a sea level rise of at least five feet very probable, even if CO₂ emissions were abruptly and dramatically reduced tomorrow.  In that scenario, the rise would be spread over the next 300 years.  If cutting CO₂ emissions is delayed or half-hearted, the five foot rise could occur within 150 years, and the sea level rise could reach 12 feet over 300 years. 

The information in the paragraphs above is all derived from careful, peer-reviewed science and has appeared in our most prestigious scientific publications.  Each item corroborates a view of a rapidly-changing world.  

Because of a variety of factors (ocean currents, latitude, the earth’s rotation, wind patterns, the different heat-absorption rates of land and water, for example), the global temperature increase is unevenly distributed, with some parts of the planet heating up much more quickly than others.  There are also natural fluctuations, such as the slight cooling in average ocean temperatures that took place between 2003 and 2005.   Given these caveats, several general statements can be made about the distribution:

• Land temperatures have risen twice as fast as ocean temperatures
• High latitudes are warming more rapidly than low latitudes
• The northern hemisphere has heated more than the southern hemisphere
• The greatest warming is taking place during the winter over northern North America and north-central Asia.

Surveying all of these changes in the world around us, scientists have been alarmed by the severity of climate impacts resulting from a rise of a single degree.  What scares the hell out of them is the consensus of those scientists who worked on the 2007 IPCC report that by the time we reach the 21st century, average air temperature will have risen--using their best estimate figures--somewhere between 3.2℉ and 7.2℉.  An added reason to worry is that, according to the World Meteorological Organization, the speed at which warming is occurring is accelerating.  

There are a number of reasons why the heating-up is speeding up, with the oceans’ diminishing capacity to absorb excess CO₂ as the largest, most worrisome factor.  Oceans have done the heavy lifting in absorbing excess CO₂, but their capacity to absorb more is declining.  Because the CO₂ oceans have already absorbed have made them 30% more acidic, and because their steadily warming waters have less absorbent capability, a larger percentage  of each ton of CO₂ emissions goes into the atmosphere each year to spur even further warming, and a smaller percentage is absorbed by the oceans.  This is one of the positive feedback loops that so frighten scientists. 

And the bad news keeps coming.  Ed Schuur, a researcher at the University of Florida, led a study which reports that the amount of carbon stored in permafrost is more than twice what was previously estimated.  That was carbon safely locked up in frozen soil for thousands of years, carbon which is already beginning to be released into the atmosphere as warming allows microbes to begin decomposing it and releasing CO₂.  The amount of carbon involved is enormous -- over a trillion metric tons of organic compounds.  Once again we see new data that indicates the 2007 IPCC report underestimated the global warming danger.  And once again we see a dangerous positive feedback loop in the making.

Another new discovery, just announced last month (December, 2012), adds more of the same.  Swiss scientists have found that as the climate warms and soil temperatures increase, shrubs have begun moving into peat bogs.  The shrubs, the scientists discovered, use compounds generated by their leaves to trigger action by mychorrizha making more nitrogen available to themselves from the soil.  Simultaneously they give out organic matter through their roots that stimulates microbes in the soil to amp up their decomposition.

The reason that is so important is that peat bogs, like permafrost, have been major storehouses of carbon; they contain a whopping 30% of all soil organic matter.  To put that into perspective, the amount of CO₂ stored by peatlands is equivalent to half of the entire amount of CO₂ currently in the atmosphere.  The two processes triggered by shrubs will, on the one hand, reduce the amount of new peat formed, and, on the other, speed up the decomposition of older peat--thus reducing the amount of new CO₂ being stored while simultaneously releasing huge amounts of old CO₂ into the atmosphere.  The potential is there to convert these historically reliable giant carbon sinks into major carbon sources--which would be very bad news indeed.  

Finally, a third discovery--also announced last month (December, 2012)--is that temperatures at the West Antarctic Ice Sheet (WAIS) are doubling at twice the rate previously believed.  In fact, the temperature record from Byrd Station, a research station in the center of the WAIS, show that the temperature there has been rising three times faster than the global average, and has climbed 4.3 degrees Fahrenheit (2.4 degrees Celsius) since 1958.  The prospects for accelerated melting and a significantly higher contribution to rising sea levels could be frightening.   

Three discoveries, each having a major impact, each revealing that we are in more trouble from global warming than we had previously suspected.  So it is no wonder that scientists are frustrated by the indifference and inaction of major governments.  The scientists have done their job.  They’ve done the studies, they’ve published their results, they’ve made recommendations, they’ve sounded the alarm, only to watch governments--especially ours in the U.S.--stall and stifle the most urgently needed reforms.  They must feel like firefighters, beating desperately on the door of a house filled with sleeping residents, while flames have begun to flare up from the roof.

The perception among a sizable portion of the general public--that’s the general public in the U.S., not the international public, which has a much better grasp of global warming realities--has been that the science on global warming is unsettled, or worse, that the whole issue is a fabrication which somehow stems from a massive conspiracy.  

These erroneous and unfortunate perceptions are largely the product of a deliberately misleading, well-documented, and all-too successful-campaign funded by the great industrial polluters and the fossil energy corporations that feed them.  Many of us have been herded by the combination of a well-orchestrated publicity campaign and uncritical media coverage into thinking that the issue is unsettled, with the arguments on one side balancing out those on the other.  (A discussion of the propagandizing effort against climate science- -among many other things--can be found later in this book, in Chapter 17, “Overarching Issues.”)  

But last year’s extreme weather events (2012) were so numerous and so unusual that the planet itself has begun to force a change in the public’s attitude.  The remarkable string of headline-grabbing events in the U.S. featured:  a “super derecho” of violent thunderstorms that strewed a 700-mile stream of wreckage behind it as it swept through the Midwest and mid-Atlantic states; the hottest July on records dating back 118 years; a drought across the majority of the contiguous states that left crops brown and soil baked and cracking, evoking comparisons with the Dust Bowl of the 1930s; the warmest sea surface temperatures in the Northeast Atlantic ever; Sandy, an October hurricane which for its combination of area impacted by sustained high winds, freakishly low pressure, heavy precipitation, flooding, and the highest storm surges ever recorded, was labeled a “frankenstorm” or “superstorm”; and a massive winter storm on Christmas Day that featured as many as 25 tornadoes, dumped snow from California to New England, and lashed Arkansas, Ohio, and Indiana with “thundersnow,” a rare combination of snow, lightning, and thunder that results from powerful upward thrusts of air in the atmosphere.  

These events certainly feel like stirrings of the “revenge of Gaia” that James Lovelock warned us was coming.  And they have captured the attention of climate change doubters, 61% of whom now acknowledge that global temperatures have risen over the past century.  This is up from 47% just three years earlier.  Follow-up interviews  with those polled showed that it wasn’t scientific reports that persuaded doubters; it was events and personal experience.  (Pollsters divide the public into believers, doubters, and deniers.  The real movement has been among the doubters, not the rigid, locked-in climate change deniers.)  When, in the course of a single calendar year, the words “derecho,” “frankenstorm,” and “thundersnow” have all been added to the national vocabulary, climate doubt has been battered by realities too powerful for many to ignore--a prime example of what Frances Moore Lappé calls “the value of a rude shock.”  

Our planet has gone through cycles of warming and cooling over its four billion year history, but the present situation is different from these natural oscillations in an alarming way.  Not just because this shift is human-generated and taking place in what would be--in geological terms--the blink of an eye, but because living things in prior shifts at least had the advantage of living in intact ecosystems.  Forests (and other biomes as well) now have to contend not only with climate change, but do so while coping with a poisoned environment; reduced, fragmented, and degraded habitat; and man-spread diseases and invasive species

I have to admit that as I began to gather and catalogue the threats global warming alone posed to forests, the number, the variety, and the severity of the threats surprised--and stunned--me.  The topic was like a Tar Baby, and I don’t doubt that despite the scope of the dangers already discussed, I’ve missed many.  Even so, the combination of threats--for anyone who understands that forests are critical to anything like life as we know it--should be frightening.  

I could put that in even stronger terms.  But throughout, I’ve tried to perform a delicate balancing act, attempting to be objective and avoid the risk of sounding extremist, on the one hand, while trying to convey the gravity of the changes confronting forests--and humankind, and unique, precious species and communities--on the other.  It hasn’t been easy.  As a civilization, we’re like people crowded in a car, while a drunk driver with his foot on the gas ignores the warnings and shrieks of sober passengers as he hurtles down a mountain road, around steep bends, sheer drop-offs, and blind curves.  But the car is our planet.  The passengers have been unable to wrest the steering wheel from the drunk.   How do you get the driver to listen?

                          © Tony Russell, 2013