Ecodisasters

Introduction

An ecodisaster is a single event or series of events that have resulted in significant and widespread destruction of a natural environment.

Ecodisasters are often rapidly evolving events, even if the consequences are still felt many years later. Examples include oil spills, nuclear accidents, airborne pollution, volcanic eruptions, and hurricanes. As scientific knowledge has increased, some ecodisasters have come to be regarded as part of a larger eco-event, such as global climate change.

Historical Background and Scientific Foundations

Human degradation of the natural environment has been a millennia-long process, extending as far back as the first, rudimentary, attempts at industrialization. For much of history, when disaster struck—through fire, battle, or the sinking of a vessel—the environmental consequences were limited. Human-caused ecodisasters destructive enough to attract global attention are a comparatively recent phenomena, occurring only when the scale of production or transportation increased to such a size that when something went wrong, the consequences on a local or regional environment could be devastating.

Before World War II (1939–1945), oil was transported in individual barrels, on tankers with relatively small holds (i.e., less than 50,000 tons), or via limited pipelines. But since the 1950s, more oil and gas have been transported through international pipelines and on supertankers. This has helped reduce the risk of frequent small spillages, but increased the risk of massive environmental trauma from large oil spills.

The most obvious danger is for an oil tanker to release its cargo to contaminate the sea and surrounding coastlines. Since some supertankers carry cargoes of 650,000 tons, clean ups can be difficult. Despite the best clean-up efforts after a catastrophic spill, some of the escaped oil will deeply impact wildlife and local eco-sys-tems.

Since such vessels came into operation from the late 1950s, the sinking of supertankers has led to dozens of ecodisasters. Although human life is seldom threatened, the environmental destruction can be far-reaching. When the ship Amoco Cadiz broke up off the coast of Brittany, France, in 1978, millions of fish were killed and 9,000 tons of oysters were destroyed. Within weeks, millions of sea urchins and other bottom dwelling species had been washed onto Brittany’s beaches and 20,000 birds were killed. Beaches, marshes, mudflats, and tidal rivers were all affected by the Cadiz’s spill. Although it was the biggest spill in history, the environmental impact was lessened by high winds and the spill’s accessibility to clean-up teams.

A decade later, the Exxon Valdez disaster resulted in a smaller slick with longer-lasting consequences. In March 1989, the Exxon Valdez struck a reef in Prince William Sound, Alaska, spilling around 38,000 tons of oil. Although thousands of Alaskans engaged in the clean-up process, the inaccessibility of the contaminated areas combined with inclement weather meant that this process was slow to begin and limited in its effectiveness. Invariably, the slick had a hugely detrimental effect on local wildlife, and the effects are longstanding. As of 2008, large areas of the Alaskan shoreline remain contaminated by the Exxon Valdez’s cargo.

Although oil pipelines are easier to manage and less prone to large-scale spillage, corrosion and sabotage mean that they can also have negative consequences for a local environment. This is most pronounced in the Niger Delta, where, over a 30-year period, oil companies and the Nigerian government have failed to address repeated oil slicks in the delta wetlands. This environmental disaster zone is compounded by regular sabotage of the pipeline.

Sometimes oil-related disasters have been compounded by the clean-up efforts. When the Torrey Canyon struck rocks off the coast of southwest England in 1967, 10,000 tons of highly toxic detergents were pumped onto the oil slicks in order to break them up. However, this worsened the oil’s impact on local wildlife.

On the other hand, technological progress has also helped prevent environmental disasters. Because of advances in cleaner fuels, air quality in the developed world has increased sufficiently. In December 1952, a cold fog saw Londoners burn more coal than normal to heat their homes; the fumes became trapped in the dense mass of cold air, poisoning the city’s residents. Some 4,000 people died in the first days of the “Great Smog,” mostly of hypoxia, and another 8,000 were killed in subsequent weeks by bronchial infections.

Industrial environmental disaster is sometimes a byproduct of technological progress. Perhaps the worst example of this occurred in December 1984, in Bhopal, India, when 40 tons of methyl isocyanate (MIC) leaked from the Union Carbide pesticide plant. Around half a million people were exposed to the highly toxic fumes, and 3,800 were killed in the immediate aftermath of its release. Up to 20,000 others have since died because of their exposure to the MIC or because of birth defects linked to the contamination. The Bhopal disaster highlighted global issues of industrial pollution and industrial safety.

Human conflict also fuels environmental disasters. During the Gulf War (1990–1991) the Iraqi army, retreating from Kuwait, set more than 700 oil wells ablaze. These fires consumed 6 million barrels of oil daily and covered parts of the Persian Gulf in thick black clouds for months. The released sulfur emissions contributed to acid rain, and local air quality was significantly diminished. Oil formed vast lakes on the Arabian Desert, contaminating soil and water.

Nuclear warfare could also present a significant global environmental risk. Scientists estimate that a global nuclear conflict could result in more than 1 billion deaths, with a similar number injured due to its effects, as well as substantial worldwide environmental damage. The U.S. atomic bombings of the Japanese cities of Hiroshima and Nagasaki in August 1945 to end World War II are used as examples of the human and environmental costs of nuclear warfare. As well as a huge loss of life, the blasts caused air pollution from dust, smoke, and particles. Fires destroyed plants and wildlife. The water table was polluted by radioactive particles, and radioactive precipitation contaminated humans and agriculture far beyond the blast zone. The regions showed an increase in birth defects and incidence of cancer.

WORDS TO KNOW

DESERTIFICATION: Transformation of arid or semiarid productive land into desert.

EROSION: The wearing away of the soil or rock over time.

EXCLUSION ZONE: A zone established by a sanctioning body to prohibit specific activities in a specific geographic area.

HYPOXIA: A condition in which cells of the body are deprived of oxygen.

INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC): The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP) in 1988 to assess the science, technology, and socioeconomic information needed to understand the risk of human-induced climate change.

OIL SLICK: A layer of oil floating on the surface of water.

SABOTAGE: The deliberate act of interference, disruption, or destruction of an opponent’s operations as part of a dispute.

SALINIZATION: An increase in salt content. The term is often applied to increased salt content of soils due to irrigation; salts in irrigation water tend to concentrate in surface soils as the water quickly evaporates rather than sinking down into the ground.

Many researchers estimate that the effects of the Japanese atomic bombings were far less severe than the likely effects of a present-day, multinational nuclear war. However, there is substantial disagreement about the likelihood of such a large-scale conflict. Many assert that nuclear warheads and other radioactive weapons are more likely to be used limitedly, in regional conflicts or by large terrorist organizations. Thus far, the deadly potential of nuclear contamination on a natural environment has only been witnessed on a handful of occasions, typically during weapons testing or accidents at nuclear power plants.

Incidents of radioactive materiel released into the atmosphere at Windscale Nuclear Power Plant in northern England and Three Mile Island, New Jersey, impacted their local environments and aroused controversy, but their long-term environmental and health impacts were minimized by swift and effective clean-up operations. However, a significant nuclear disaster occurred at the Chernobyl nuclear power plant, near Pripyat in the Soviet Union (now Ukraine) in April 1986. A steam explosion at the plant led to a series of further explosions and fires, causing nuclear meltdown. Workers at the plant and some residents of Pripyat, which was evacuated and abandoned, experienced dangerous doses of radiation, and hundreds suffered radiation sickness, from which around 30 immediately died. Radioactive waste contaminated the Dnieper River reservoir system, causing short-term pollution to drinking water, but long-term contamination of fish. Wildlife and animals in the vicinity of the Chernobyl plant died. This included a small pine forest, dubbed the “Red Forest,” which turned light brown and completely died. A large exclusion zone, which resulted in the evacuation of around 220,000 residents, was formed around the plant. This remains a prohibited area. Radioactive particles in the area are periodically re-dispersed into the atmosphere by localized fires.

During the Chernobyl explosion, radioactive particles also billowed into the atmosphere causing a huge radioactive cloud that dispersed all over Europe. In the short term, radioactive precipitation contaminated some crops and livestock far from the disaster zone. It contributed to a higher incidence of cancer rates in several countries, especially parts of Belarus, which shares a border with Ukraine near the Chernobyl site. Greenpeace has claimed that higher cancer rates attributable to Chernobyl led to an additional 200,000 deaths in the former USSR alone between 1990–2004, although health experts have challenged such figures, and claim cancer deaths directly attributable to the disaster are much lower.

One of the most significant problems with the Chernobyl disaster was that the Soviet government attempted to cover up what had happened for several days. Even when the world became aware of the problem—after Swedish scientists detected the radioactive cloud soon after meltdown—the Soviet government resisted international offers of technical assistance, compounding the disaster’s human and environmental impacts.

One of the most significant eco-disasters, both in terms of scale and environmental cost, to emerge from the Soviet-era is the silting of the Aral Sea. This occurred over a number of decades, beginning in the 1920s, after the Soviet regime used the Aral’s tributary rivers to irrigate Uzbekistan’s cotton plains. This eventually caused the sea to shrink to one quarter of its original size, increasing salinity fivefold and killing fauna and other wildlife. The drying up of the Aral Sea also affected the local microclimate, leading to crop failure and toxic fertilizer run off. This problem was compounded by the Soviet Union’s use of the Aral as a dumping ground for waste, including industrial wastes and hazardous materials from weapons development. Although the government of Kazakhstan has invested heavily in refilling the northern Aral Sea with some success, the disappearance of the Aral remains among the worst human-made environmental disasters in history. A similar scenario has been witnessed in Lake Chad, in central Africa. The lake was once one of the largest in the world, but irrigation and damming projects have combined to reduce it to just 5% of its former size.

Ecodisasters also result from over-farming. In many developing nations, farmers plant crops year after year without preventing soil depletion. This leads to low crop-yields, crop failure, food scarcity, soil erosion, and desertification. However, environmental degradation resulting from over-intensive agriculture is not unique to developing economies. The famous “Dust Bowl” on North America’s Great Plains in the 1930s was caused by over intensive farming—without crop rotation or the techniques that are commonly used to limit the effects of soil erosion—combined with drought. The resulting barren soil and dust was then whipped up by winds and carried around North America in huge clouds. Millions of tons of nutrient-rich topsoil were lost in dust storms so severe that they caused virtual blackouts in the middle of the day, leaving houses, roads, and fields buried by dust and sand. Dust settled as far east as New York City, and ships 300 mi (480 km) from America’s eastern seaboard reported dust accumulation on board. Although the nutrients that enrich soils take centuries to accumulate, these losses were masked in later decades by significant advancements in fertilizer technology. At the height of the droughts, the United States was in the Great Depression, a time of severe economic crisis. Large numbers of people seeking work migrated from the Dust Bowl, leading to significant depopulation of farmlands and the disappearance of many small towns.

Although humans have a sustained some negative impacts on the environment, natural disasters can also cause massive environmental damage. For example, major volcanic explosions can send dust particles and noxious gases into the atmosphere. In 1783 the Laki volcano, on the southern side of Iceland, exploded, expelling enough molten lava to bury Manhattan Island to the top of the Rockefeller Center. It sent a poisonous plume of smoke skyward, witnessed over following weeks as far south as Tripoli in Syria, and as far east as Baghdad. Dust-particle air pollution contributed to deaths in Britain and France, where as much as 5% of the population may have died. In Iceland, acid rain destroyed much of the island’s livestock and caused a famine that wiped out a quarter of its population. The light-scattering effects of volcanic gases in the upper atmosphere reduced the amount of solar energy reaching Earth and causing huge temperature fluctuations, even thousands of miles away. The United States suffered one of its longest and coldest winters, with temperatures averaging 40°F below norms for today. In Japan, exceptional cold destroyed rice crops and one million people perished in a subsequent famine. Disruption of the monsoons affected water levels on major African Rivers and destroyed irrigation systems. Around one sixth of Egypt’s population fled or perished. Major volcanic eruptions in Indonesia at Tambora in 1815, and Krakatau in 1883, also had significant effects on global climate, while other volcanoes, such as that at Nevada Ruiz in Colombia in 1985, have had devastating effects on local environments.

Although the effects of earthquakes on humans and cities can be devastating, their environmental implications are typically narrower. Urbanized settings are most at risk, where toppled buildings are the main cause of death and injury. Fire remains the principal post-earthquake environmental risk, with pollutants expelled into the atmosphere in clouds of smoke. Combining with swells of seawater, undersea earthquakes are more deadly. The 2004 Asian tsunami, as well as claiming around 160,000 lives, destroyed beaches, damaged coral reefs, polluted groundwater, put dozens of animal species in danger of extinction, changed the contours of land and rivers, and rendered useless vast amounts of farm land.

Hurricanes also provide a potent threat to both natural and urban settings. Common effects include soil erosion, salinization, and disruption to natural habitats and breeding grounds. Sometimes such impacts merely have an ephemeral effect, but when a hurricane unleashes its force on an urban environment, it can give rise to a full-scale ecodisaster. In August 2005, the United States suffered Hurricane Katrina, its most devastating hurricane in more than 75 years. As well as killing more than 1,800 people and having a devastating effect on local wildlife habitations, untreated residual waters—containing a mixture of debris, raw sewage, heavy metals, industrial pollutants, fertilizers, oil, and pesticides—were pumped from the city and dumped into Lake Pontchartrain, with potentially devastating environmental effects.

Impacts and Issues

Ecodisasters can essentially be seen as falling into two categories: natural catastrophes and human-induced disasters. The former—earthquakes, volcanic eruptions, and hurricanes and other large storms—are ever-present threats. However, humans can minimize the environmental impacts of natural disasters by carefully planning development and implementing effective clean-up strategies. Since our lives, cities, farms, and environment are impossible to separate, researchers have begun to evaluate ecodisasters by looking at the total damage caused by both human and natural forces. For example, a monsoon may cause flooding, but improper storage of toxic chemicals or the building of structures in an uncontrolled flood zone may add to the total environmental impact of the storm.

Until comparatively recently, climate change was considered an irreversible, wholly natural phenomenon. Global warming was thought to be a periodic fluctuation

IN CONTEXT: ECODISASTERS

Some environmental disasters are caused by natural climate or weather events. These include wildfires, landslides, floods, earthquakes, drought, tornadoes, tsunamis, and volcanic eruptions.

Although the cause of these natural environmental disasters are not directly related to human activity (although there is continued study and evidence that human driven climate change may increase the frequency and intensity of some types of storms), in some cases the effects are worsened by, the influence of humans. For example, in the wake of the Indian Ocean tsunami of 2004, the environments suffering the most damage were those where urban development and construction had damaged coral reefs. In places where coral reefs were healthy, the reef acted like a buffer, deflecting the power of the giant wave.

A second category of environmental disasters includes those that are directly caused by human activities. Examples of human-induced environmental disasters include oil spills, chemical spills, and nuclear disasters. In addition, the toll taken by the environment during wars and as a result of terrorist activity can be disastrous to ecosystems. In many cases environmental disasters that are the result of human activities have longer lasting effects on the environment than catastrophes caused by natural events.

in the planet’s temperature, like the last ice age. Now, an overwhelming majority of scientists have made an irrefutable connection between human activity and global warming.

The assessments of the Intergovernmental Panel on Climate Change (IPCC) have played an important part in informing the debate on climate change. Although its First Assessment report, published in 1990, was unable to definitively conclude whether fluctuations in the planet’s temperature were due to “natural variability” or “human factors,” its Second Assessment report, published in 1995, found “a discernible human influence” on global climate change. However, by the time of its Fourth Assessment report, published in 2007, it stated that evidence of human-caused climate change was “unequivocal.”

According to the IPCC, likely outcomes of climate change are devastating for many regions of the world. Such effects include sea-level rise and flooding or loss of low-lying coastal regions; droughts; soil erosion; famines resulting from decreased food production in tropical and sub-tropical regions; and social and economic problems resulting from migration.

Primary Source Connection

The following news article recognizes the depletion of trees in areas of the United States that have been affected by Hurricane Katrina—an estimated 320 million acres worth—and the intentions and efforts to replant much of this area, while observing the obstacles facing this challenge. Research has revealed that Katrina is the largest ecological disaster in U.S. history. Other environmental effects of the storm include greenhouse gases given off from the rotting trees, and invasive species of plants that compete for the space and nutrients once occupied by the coastal forest.

KATRINA RATED LARGEST U.S. ECODISASTER

No surprise: They love trees in Poplarville, Miss. So when hurricane Katrina ripped out tulip poplars, bent black gum to the ground, and scattered loblolly pines like pick-up sticks, local tree enthusiasts such as Julia Anderson not only had a rude aesthetic shock, but many also sensed that the destruction had shaken the very roots of the region’s ecological balance.

Now, scientists using NASA satellite imagery have at least partly confirmed those suspicions. From vast slash pine plantations to river-bottom hardwood stands, hurricane Katrina killed or damaged about 320 million trees across Florida, Mississippi, Louisiana, Alabama, and Texas—the largest ecological disaster in US history, new estimates reveal. Confronting a potential 100 million metric tons of greenhouse gases seeping from rotting logs and leaves, the proliferation of nonnative plants, and a spike in wildfire risks, scientists and residents alike are raising new questions about the storm’s environmental legacy.

Perhaps the most critical one: Can Katrina-like storms contribute to an ecological “feedback loop,” in which carbon being released from fallen, decaying forests raises the occurrences of storms and, in turn, intensifies the effects of global warming? The good news is that resilient and fast-growing Southern forests, with the help of humans, may be able to temper the phenomenon.

“The problem with feedback is that it’ll make climate change worse than the current scenarios are envisioning,” says George Hurtt, a natural-resources professor at the University of New Hampshire in Durham and coauthor of a new damage assessment published Friday in the journal Science. “Katrina left a huge carbon footprint, and there are going to be constant reminders of that.”

The storm killed or damaged nearly one big tree for every American, and the total load of carbon dioxide produced by their decay surpasses the amount of CO2 that all healthy forests in the US could photosynthesize back into oxygen in a year’s time. Moreover, a recent Louisiana State University study showed that, across history, wildfires have consumed hurricane-wrecked areas on the Gulf Coast. Such fires, too, can play into the carbon feedback loop, says Professor Hurtt.

At the same time, escaped Asian ornamentals—including Chinese tallow, the pesky privet bush, and congongrass (a forest-floor bully that swamps all competitors)—will probably complicate or delay regrowth in some parts of the forest.

“It actually is hard to find a silver lining,” says Jim Shephard, a forestry professor at Mississippi State University (MSU) in Starkville.

Some critics, however, say that in their reach to connect Katrina’s damage to global warming, researchers from UNH and Tulane University in New Orleans may have done better by employing forestry techniques such as on-site surveys.

The Tulane and UNH estimate of the storm’s damage is “way, way, way too much,” says Wayne Tucker of the Mississippi Institute for Forest Inventory (MIFI) in Jackson.

Instead of looking at a small number of test plots, MIFI conducted more than 150 on-the-ground surveys on randomly selected plots in each affected county. Revising early estimates of about 3 billion lost board feet, state forestry experts finally figured the storm ruined about 1 billion board feet—one-fifth of the estimate published in Science, according to Mr. Tucker.

“Their analysis on imagery is probably pretty good, but where they fell down was their sampling method,” he says.

Mississippi researchers agree, however, that the damage transformed the ecological and economic equation for landowners and residents. Tellingly, paper and lumber companies are switching from fast-growing but relatively fragile loblolly pines—which fell in droves during Katrina—to the slower-growing but deeper-rooted longleaf pine. Private and state nurseries are sold out of longleaf seedlings.

What’s more, Congress for the first time approved money—$504 million—to help states replant lost forests, but only a fraction of that money has so far been allocated. One problem: Because the US has never before compensated tree owners, the program employs a formula used to assess cotton crop damages—a poor fit that has put the project behind schedule.

Congress also provided tens of millions of dollars for states to buy firefighting equipment, which has already been used to cut hundreds of miles of new firebreaks. In fact, with about half the fallen lumber salvaged, the worst fire fears are over, says Mr. Shephard at MSU.

But trees define life in Mississippi more than in simply dollar terms, says Ms. Anderson, the Poplarville resident and coordinator of a replanting effort in Pearl River County. Today, the resuscitation effort is driven largely by residents keen to see the return of the canopy, which defined many people’s sense of place.

Replant South Mississippi, a private effort, hopes in the next three years to replace 300,000 lost trees, including elder, pecan, poplar, black gum, Chickasaw plum, bald cypress, red buckeye, pawpaw, 10 varieties of oak, and bigleaf magnolia.

“My best, most fun activity was to walk in the woods, and now almost every tree is gone,” says Anderson. “I can’t even go walk where I used to because of all the dead trees. I’ve gained 20 pounds since the storm.” Blessed with long growing seasons and favorable weather, the region is expected to see much of the canopy regrow within 15 years, experts say.

Patrik Jonsson

JONSSON, PATRIK. “KATRINA RATED LARGEST U.S. ECODISASTER.” CHRISTIAN SCIENCE MONITOR (NOVEMBER 19, 2007).

See Also Air Pollution; Climate Change; Dust Storms; Oil Spills; War and Conflict-Related Environmental Destruction

BIBLIOGRAPHY

Books

Gunn, Angus. Unnatural Disasters: Case Studies of Human-Induced Environmental Catastrophes. Westport: Greenwood Press, 2003.

Ingrahm, Scott. The Chernobyl Nuclear Disaster. New York: Facts on File, 2005.

Periodicals

Hobbs, Peter V., and Lawrence F. Radke. “Airborne Studies of the Smoke from the Kuwait Oil Fires.” Science256, no. 5059 (May 15, 1992): 987-991.

Schubert, Siegfried D., et al. “On the Causes of the 1930s Dust Bowl.”Science 303, no. 5665 (March 19, 2004): 1855–1859.

Web Sites

Economist. “The Summer of Acid Rain.” December 19, 2007. http://www.economist.com/world/international/displaystory.cfm?story_id=10311405 (accessed March 6, 2008).

National Environment Research Council. “What Will Climate Change Mean for Our World?” http://www.nerc.ac.uk/research/issues/climatechange/globalimpact.asp (accessed March 6, 2008).

James Corbett