Editor's note: The climate is changing, but is it humankind's fault? Daniel B. Botkin, professor Emeritus in the Department of Ecology, Evolution, and Marine Biology at University of California Santa Barbara, doesn't believe so. In the following column, he dissects the conclusions reached by the Union of Concerned Scientists in its report, National Landmarks at Risk, How Rising Seas, Floods, and Wildfires Are Threatening the United States' Most Cherished Historic Sites.
For those of us who love our national parks and are confronted daily with media, politicians, and pundits warning us of a coming global-warming disaster, it's only natural to ask what that warming will mean for our national parks. This is exactly what the well-known Union of Concerned Scientists discuss in their recent report, National Landmarks at Risk: How Rising Seas, Floods, and Wildfires Are Threatening the United States' Most Cherished Historic Sites.
I've done research since 1968 on the possibility of human-caused global warming and its possible ecological effects, and have published widely on this topic, discussing possible effects on biodiversity and on specific endangered species as well as on forests, cities, and historical evidence of Arctic sea ice change. I've also been involved in the development of some aspects of some climate models, and having developed a computer model of forests that is one of the principal methods used to forecast global warming effects on vegetation, I sought out the UCS report with great interest.
The approach the Union has taken is to have the report written by four staff members: Debra Holtz, a journalist; Kate Cell, a fund-raiser for the organization; Adam Markham, with a B.S. in zoology, who was the founder of Clean Air-Cool Planet, a nonprofit organization 'to promote innovative community-based solutions to climate change in the Northeast'; and Brenda Ekwurzel, the Union's Senior Climate Scientist. She is the only author with research experience on the subject, has a Ph.D. in isotope geochemistry from the Department of Earth Sciences at Columbia University's Lamont-Doherty Earth Observatory and has been on the faculty of the University of Arizona Department of Hydrology and Water Resources.
These four authors took the standard reports from such organizations as the United National Intergovernmental Panel on Climate Change, treating them as accurate and true, and then discussed the implications for 16 American historic sites. As shown in the accompanying table, they write that 11 of the sites are threatened by rising sea levels and their consequences (coastal erosion and flooding); two by inland flooding; two by wildfires; and one by 'extreme heat and drought' (table 1).
The report opens with a bold assertion: 'Many of the United States' iconic landmarks and heritage sites are at risk as never before. Sea level rise, coastal erosion, increased flooding, heavy rains, and more frequent large wildfires are damaging archaeological resources, historic buildings, and cultural landscapes across the nation.' The report later goes on to add, 'All of the case studies in this report draw on observations of impacts that are either consistent with, or attributable to, human-induced climate change based on multiple lines of scientific evidence.' To which the authors add, 'This report sounds a wake-up call: as the impacts of climate change continue, we must protect these sites and reduce the risks."
The point of the report, its opening theme and its major conclusion, is that these historic places are in trouble and it's our fault, we have been the bad guys interfering with nature and therefore damaging places we value. This is consistent with the IPCC 2014 report and the 2014 White House Climate Change Assessment, for both of which I acted as an expert reviewer and testified before the House and Senate about.
TABLE 1. HISTORIC SITES AND CLAIMED THREATS TO THEM
Threatened by Sea Level Rise and Accompanying Flooding
- Boston's Faneuil Hall and surroundings
- Statue of Liberty and Ellis Island
- Harriet Tubman National Monument Monument
- Historic Jamestown, VA
- NASA's coastal facilities
- Annapolis, MD
- Fort Monroe National Monument
- Cape Hatteras Lighthouse
- Bering Land Bridge National Monument & Shishmaref; Cape Krusenstern National Monument, including Kivalina Native Villages and Ancestral Lands
- Pu'uhonua O Honaunau & Kaloko-Honokhau National Historical Parks
- Prehistoric Florida shell structures
Threatened by Future Floods
- Charleston, SC; Historic St. Augustine, Fl and Castillo De San Marcos
Threatened by Wildfires (and perhaps also flooding)
- Mesa Verde National Park and Bandelier National Monument & Santa Clara Pueblo
- Groveland, CA and other California Gold Rush era towns
Threatened by Extreme Heat and Drought
- Cesar Chavez National Monument, California
Back Bay Fens Park and Jamaica Bay National Wildlife Refuge
Reading the dire forecasts of the UCS report, I thought immediately about two seaside places familiar to me: Back Bay Fens Park in Boston and Jamaica Bay National Wildlife Refuge in New York City. Back Bay Fens park was designed by Frederick Law Olmsted, the famous landscape architect known especially for designing New York City's Central Park. Back Bay was a problem because it was a landfill on Boston's shore that flooded frequently, which caused various problems.
To understand what Olmsted did in designing Back Bay, one has to step back and consider Boston's original site, which had certain advantages for a major city: a narrow peninsula with several hills that could be easily defended, a good harbor, and a good water supply. But as the city grew, demand increased for more land for buildings, a larger area for docking ships, and a better water supply. The need to control ocean floods and to dispose of solid and liquid wastes grew as well. Much of the original tidal flats area, which had been too wet to build on and too shallow to navigate, had been converted, before Olmsted got involved, to flat land --- hills cut away and the marshes filled with their soil. The filling of Back Bay began in 1858 and continued for decades.
Olmsted's solution to the flooding and sewage pollution was a water-control project he called the "fens." His goal was to "abate existing nuisances" by keeping sewage out of the streams and ponds and building artificial banks for the streams to prevent flooding'and to do this in a natural-looking way. His solution included creating artificial watercourses by digging shallow depressions in the tidal flats, following meandering patterns like natural streams; setting aside other artificial depressions as holding ponds for tidal flooding; restoring a natural salt marsh planted with vegetation tolerant of brackish water; and planting the entire area to serve as a recreational park when not in flood. He put a tidal gate on the Charles River'Boston's major river'and had two major streams diverted directly through culverts into the Charles so that they flooded the fens only during flood periods. He reconstructed the Muddy River primarily to create new, accessible landscape.
The result of Olmsted's vision was that control of water became an aesthetic addition to the city. The blending of several goals made the development of the fens a landmark in city planning. Although to the casual stroller it appears to be simply a park for recreation, the area serves an important environmental function in flood and sewage control. Confronted with the combined problems of ocean surges and flooding from river runoff inland, Olmsted did not waste his time complaining about whether or not people have caused the problem. He just set out and solved it.
Jamaica Bay National Wildlife Refuge, although not directly planned to solve flooding problems, does so in much the same way that the Boston Back Bay Fens does. The Refuge has become one of my favorite places in New York City. It is the largest migratory bird sanctuary in the northeastern United States. It is the only wildlife sanctuary that is part of the National Park System, and it lies within the city of New York, in view of the Empire State Building, as my accompanying photograph shows. New York City residents wanting contact with nature can get there by public transportation.
The Refuge faces the Atlantic Ocean and New York's outer harbor and includes inlets and wetlands directly connected to the Sound. The refuge was damaged during tropical storm Sandy, but it served the same multiple functions that Back Bay does in Boston ' it acted as a buffer between that major ocean storm and city structures inland.
As I read the UCS report, Back Bay Fens and Jamaica Bay Refuge were in mind as what to do about coastal flooding along cities. Then I went to the scientific evidence that should be forming the basis for the UCS report, and which I will turn to now.
The Scientific Evidence
What is the evidence that sea level is rising, that wildfires, drought, and episodes of very high temperatures are increasing, and what is the evidence that such changes are our fault? Let's take them one by one.
As is well-known, we are blamed for causing a global warming mainly because our burning of fossil fuels is increasing the carbon dioxide (CO2) concentration in the atmosphere. Since this is a greenhouse gas, we must be warming the climate.
Yes, carbon dioxide, the greenhouse gas that gets so much attention, has increased greatly and rapidly, from 280 parts per million to 400, and as this graph shows, it is continuing that rapid rise.
Has Earth been warming?
Climate has always changed and is always changing. The last Ice Age, which covered places like what is now New York City with ice two miles deep, ended between 17,000 and 12,500 years ago, with overall but highly variable warming since then. Among the variations during the last thousand or so years, there was a warming period lasting approximately 300 years, from A.D. 950 to 1250, known as the Medieval Warm Period (warming compared to what climatologists today call 'normal,' taken in general by today's climatologists to mean the average surface temperature during the past century between 1960-1980 or between 1960'1990). This is the time when Vikings settled Greenland and reached North America, and when in the southern Pacific the Polynesians did a lot of their expansion among far-flung Pacific islands.
The Medieval Warming was followed by the 'Little Ice Age,' which lasted from approximately mid-1400 to 1700 A.D and somewhat later. Crop failures occurred in western Europe, and some mountain glaciers in the Swiss Alps advanced to the extent that they filled valleys and destroyed villages. Areas to the north that had enjoyed abundant crop production were under ice. This was the time when the human population was devastated by the Black Plague, whose effects may have been exacerbated by poor nutrition as a result of crop failures, and by the damp and cold that reached out across Europe and even to Iceland by about 1400. It was also the time of the early European settlement of the United States. As I have written elsewhere, when the Pilgrims said it was a cold winter, it was a very cold winter.
A warming trend started in the mid-nineteenth century. This was interrupted from about 1940 to 1960 by a cooling, and then the temperature rose until about 20 years ago. An important scientific paper published September 1 this year states that Earth's surface temperature has not changed for the past 19 years, and 16-26 years for the lower atmosphere. That's the conclusion of University of Guelph statistician and Professor of Economics Ross R. McKitrick, who used a novel kind of statistical analysis. He points out that this lack of warming is of "particular note because climate models project continuing warming over the period. Since 1990, atmospheric carbon dioxide levels rose from 354 ppm to just under 400 ppm, a 13% increase."
Carbon dioxide is definitely continuing to increase in the atmosphere, but Earth's surface and atmospheric temperatures aren't tracking it. Even though our activities are adding carbon dioxide rapidly to the atmosphere, it seems to be having no effect right now on Earth's average surface and lower atmosphere temperature.
However, the UCS report blithely comments, 'Climate models show that if our emissions of carbon dioxide and other heat-trapping gases remain high, Bakersfield could have almost 50 days of extreme heat, with temperatures reaching 104Â°F or more, by 2050'up from four days a year on average between 1961 and 1990.'
But if the temperature has not changed in 19 to 26 years, then how much credence can we give to this assertion? We must ask whether the climate models have been accurate predictors of recent climate change.
John Christy, the climatologist who is said to be the primary person responsible for the development of satellites that measure Earth's temperature, compared the combined forecasts of major global climate models with observed temperature change since 1980. As you can see in his graph, there is no correspondence. The climate models do not even come close to forecasting actual temperature change; they forecast a huge, steady increase. In contrast, as you can see in the graph, the temperature has varied a little, as it always does, but as the new paper that I mentioned earlier asserts, it has not changed.
John Christy's Comparison of Global Warming Model Forecasts
Actual Temperature Change since 1980 (Courtesy of John Christy, Alabama State Climatologist)
Thus the climate models cannot be considered reliable bases for forecasting the future. Indeed, other experts on model validation say that the climate models have never been sufficiently validated in any other ways as well, and therefore are not an accurate representation of the real world we live in. Conclusion: our addition of carbon dioxide to the atmosphere does not appear to be increasing Earth's temperature.
Whatever is happening to Earth's climate does not seem to be our fault.
Sea Level Rise
What about the claim that sea level rise is another factor 'damaging archaeological resources, historic buildings, and cultural landscapes across the nation? Well, the sea level has been rising since the end of the last Ice Age, starting about 14,000 years ago as the continental and mountain glaciers have melted and sea water has expanded with the overall warming. The average rate has been about a foot or two a century (about 23-46 cm per century). Data suggest that the rate was much greater until about 8,000 years ago.
Yes, sea-level rise is definitely a problem, but it is not a problem simply because it is our fault. It is a problem that we just haven't bothered to face up to in any serious way until the global warming issue captured our attention. Whether or not we are adding to the rate of sea level rise, this is causing problems and will continue to cause problems. It would be a mistake to focus on it only if we were convinced it was our fault. For many years past, we should have been planning for sea level rise, and we need to make this an important environmental priority.
Frequency of Severe Storms
The main concern often expressed about sea levels is that severe ocean storms do greater damage than indicated by the simple rise in the water level. Therefore, it is necessary for us to look at how the frequency of severe storms has changed over time. Underlying the claim by the UCS report that 12 of the 16 sites are in danger of flooding is the assumption that the frequency of severe storms has increased, as have their landfalls. But the graphs below of severe storm frequency, show variation over time but no overall increase. Therefore, during the recent past the claim by the UCS report is contradicted. And since the climate models don't even come close to forecasting temperature change, we cannot trust them to forecast changes in storm frequency.
Number of Severe Storms affecting the United States since 1970
(Courtesy of Roger Pielke Jr., Professor in the Environmental Studies Program, University of Colorado, from his House of Representatives Testimony 11 December 2013)
Frequency of Extremely Hot Days
This is controversial, because it is difficult to get information that summarizes these trends for the entire United States, and there are a variety of opinions and discussions about these data, so I put this into the article with some caution to the reader. But several graphs indicate that there has not been an increase in the average number of very hot days. For example, this graph shows days with temperatures above 95Â° F. This graph is based on the summary from all United States Historical Climatology Network weather stations that have been in operation since 1930.
Wildfire Frequency in the U.S. Has Not Increased
The UCS report claims that two historic sites within the National Park System are being, and will be, damaged by increases in wildfire frequency. But once again, a graph from the U.S. government agencies involved, of number of wildfires, shows no increase.
Furthermore, it is well-established that most major wildfires that occur these days are from the failure to allow much more frequent, and therefore light fires, to burn. The 20th century policy dominated by Smokey Bear ' 'only you can prevent forest fires' ' and the belief, ill-founded, that all forest and grassland fires are bad and must be prevented ' have had a damaging effect.
(Source EPA http://www.epa.gov/climatechange/)
As I wrote in my latest book, The Moon in the Nautilus Shell, this Smokey Bear policy also caused the near-extinction of Kirtland's warbler, which nests in young jack pine, a tree species that regenerates only after fire. It was only when ornithologists realized the population had dropped in half in a decade and that fire suppression was the cause that the Audubon Society, the U. S. Fish and Wildlife Service, and the state of Michigan began prescribed burning programs.
As I also discuss in that book, excellent work by Professor Wallace Covington of Northern Arizona University, involving careful historical analysis of the pre-European ponderosa pine forests of that state, followed by careful removal of excess fuel and trees, followed by prescribed burns every 3 to 5 years, as was the natural rate---restored some of these forests to their beautiful and natural condition: large pines widely spaced with grasses filling the land between. In contrast, next door to his experimental forests is one of The Nature Conservancy ponderosa pine protected, no-touch areas, which does not resemble the pre-European ponderosa pine forests at all, but instead forms a very dense stand of young, small trees and a lot of fuel on the ground, just waiting for a wildfire.
Carefully managed Ponderosa Pine Forest, with excess fuel built up over more than a century removed and light fires every 3 to 5 years (Photo by the author)
Next to the strongly managed forest is a Nature Conservancy no-touch Ponderosa Pine Preserve. (Photo by the author)
What Should be Done About Sea Level Rise and Wildfires and Our National Parks?
As I have shown, observations do not support the claim that our activities are currently warming the globe. Does this mean that we should stop worrying about climate change? Of course not. Because sea level has been rising for thousands of years, the encroachment of ocean waters and damage from ocean storms have been problems for coastal structures, which we have just ignored. We have to face up to these. But arguing about whether this is our fault or not is beside the point and detracts us away from doing anything useful, as we focus instead of what can best be called a fairy-tale debate. The same must be said about wildfires. For decades, experts on wildfires have been calling for improved management of America's forests, and the need remains important. We must remember Frederick Law Olmsted's approach to designing the Back Bay Fens--- solve the problem, do not waste your time arguing if we are to blame.
However, global warming has become the sole focus of so much environmental discussion that it risks eclipsing much more pressing and demonstrable environmental problems. The major damage that we as a species are doing here and now to the environment is not getting the attention it deserves.
We need to keep in mind the reality of Nature, which I have portrayed in a replacement for Smokey Bear: Morph the Moose (Copyright and trademarked by the author).