Climate change has already brought alarming change to Tasmania, the huge island south of the Australian mainland. Until recently it was assumed that the climate differences would not be massive since it was thought by some that the ocean surrounding the island would not be heating as quickly as it was in other areas.
Now the southwest area of the state, the heart of its world heritage area, is being described as dying — the rainforest and heathlands are beginning to disappear. The nearby seas, it turns out, are warming at two to three times the global rate.
Richard Flanagan writes about this issue in an opinion article at The Guardian. Below is an excerpt:
…Then there was the startlingly new phenomenon of widespread dry lightning storms. Almost unknown in Tasmania until this century they had increased exponentially since 2000, leading to a greatly increased rate of fire in a rapidly drying south-west. Compounding all this, winds were also growing in duration, further drying the environment and fuelling the fires’ spread and ferocity.
Such a future would see these fires destroy Tasmania’s globally unique rainforests and mesmerizing alpine heathlands. Unlike mainland eucalyptus forest these ecosystems do not regenerate after fire: they would vanish forever. Tasmania’s world heritage area was our Great Barrier Reef, and, like the Great Barrier Reef, it seemed doomed by climate change.
Later [Prof Peter] Davies [an eminent water scientist] took me on a research trip into a remote part of the south-west to show me the deeply upsetting sight of an area that was once peatland and forest and was now, after repeated burning, wet gravel. The news was hard to comprehend – the enemies of Tasmania’s wild lands had always had local addresses: the Hydro Electricity Commission, Gunns, various tourism ventures. They could be named and they could be fought, and, in some cases, beaten.
Six weeks ago, the future that Davies and others had been predicting arrived in Tasmania. Lightning strikes ignited what would become known as the Gell River fire in the island’s south-west. In later weeks more lightning strikes led to more fires, every major one of which is still burning.
By mid-century western wildfires could increase 200% to 600%
At 2 p.m. Friday on the day after Thanksgiving President Trump’s administration released an important document about our climate. Required every four years by a 1990 act of Congress, the Fourth National Climate Assessment focuses on the human welfare, societal, and environmental elements of climate change.
Surprising in its bluntness, it lays out the devastating effects on the economy, health, environment, and wildfires. Within the 1,656-page document wildfires are covered rather extensively and photos of fires are used several times in the headers of sections, like the one below for Chapter 1 (which may have been taken at the Howe Ridge Fire in Glacier National Park in Montana in August).
The scientists concluded that by the middle of this century, the annual area burned in the western United States could increase 2–6 times from the present, depending on the geographic area, ecosystem, and local climate. The area burned by lightning-ignited wildfires could increase 30 percent by 2060.
In the Southeast rising temperatures and increases in the duration and intensity of drought are expected to increase wildfire occurrence and also reduce the effectiveness of prescribed fire. Intra-annual droughts, like the one in 2016, are expected to become more frequent in the future. Thus, drought and greater fire activity are expected to continue to transform forest ecosystems in the region.
In the Southwest, recent wildfires have made California ecosystems and Southwest forests net carbon emitters (they are releasing more carbon to the atmosphere than they are storing). With continued greenhouse gas emissions, models project more wildfire across the area. Under higher emissions, fire frequency could increase 25%, and the frequency of very large fires (greater than 5,000 hectares) could triple.
The Northwest is likely to continue to warm during all seasons under all future scenarios, although the rate of warming depends on current and future emissions. The warming trend is projected to be accentuated in certain mountain areas in late winter and spring, further exacerbating snowpack loss and increasing the risk for insect infestations and wildfires. In central Idaho and eastern Oregon and Washington, vast mountain areas have already been transformed by mountain pine beetle infestations, wildfires, or both, but the western Cascades and coastal mountain ranges have less experience with these growing threats. Forests in the interior Northwest are changing rapidly because of increasing wildfire and insect and disease damage, attributed largely to a changing climate. These changes are expected to increase as temperatures increase and as summer droughts deepen.
Below are wildfire-related excerpts from the report.
Chapter 1: Overview
The impacts of climate change and extreme weather on natural and built systems are often considered from the perspective of individual sectors: how does a changing climate impact water resources, the electric grid, or the food system? None of these sectors, however, exists in isolation. The natural, built, and social systems we rely on are all interconnected, and impacts and management choices within one sector may have cascading effects on the others.
In the natural world one environmental event or disturbance can initiate or be part of a series of cascading events that intensify the impacts of natural hazards, possibly turning them into disasters.
An article at The Conversation explores how these effects can be enhanced by a warming climate. Below is an excerpt from an article written by Amir AghaKouchak (UC Irvine) and Farshid Vahedifard (Mississippi State University).
“Multiple hazardous events are considered cascading when they act as a series of toppling dominoes, such as flooding and landslides that occur after rain over wildfires. Cascading events may begin in small areas but can intensify and spread to influence larger areas.
“Also, the severity of these cascading weather events worsens in a warming world. Drought-stricken areas become more vulnerable to wildfires. And snow and ice are melting earlier, altering the timing of runoff. This has a direct relationship with the fact that the fire season across the globe has extended by 20 percent since the 1980s. Earlier snowmelt increases the chance of low flows in the dry season and can make forests and vegetation more vulnerable to fires.
“These links spread further as wildfires occur at elevations never imagined before. As fires destroy the forest canopy on high mountain ranges, the way snow accumulates is altered. Snow melts faster because soot deposited on the snow absorbs heat. Similarly, as drought dust is released, snow melts at a higher rate, as has been seen in the Upper Colorado River Basin.
“When landscapes are charred during wildfires, they become more vulnerable to landslides and flooding. In January, a debris flow event in Montecito, California killed 21 people and injured more than 160. Just one month before the landslide, the soil on the town’s steep slopes were destabilized in [the Thomas Fire]. After a storm brought torrential downpours, a 5-meter high wave of mud, tree branches and boulders swept down the slopes and into people’s homes.”
The climate warming that we have been seeing is expected to continue along with the increased risk of larger, more suppression-resistant wildfires. Scientists have examined how this will affect fires in Europe up to a 1.5°C rise, which is the not-to-exceed target in the Paris climate agreement. Now a study is complete that examines increases of 1.5, 2, and 3°C warming scenarios. Not surprisingly, it found that the higher the warming level, the larger is the increase of burned area, ranging from ~40% to ~100% across the scenarios. Their results indicate that significant benefits would be obtained if warming were limited to well below 2 °C.
The paper, published in Nature, was written by Marco Turco, Juan José Rosa-Cánovas, Joaquín Bedia, Sonia Jerez, Juan Pedro Montávez, Maria Carmen Llasat, and Antonello Provenzale.
In a tweet Sunday afternoon President Trump said the wildfires in California are “magnified & made worse by the bad environmental laws which aren’t allowing massive amount of readily available water to be properly utilized. It is being diverted into the Pacific Ocean. Must also tree clear to stop fire spreading?”
It is nonsensical to think that water projects, whether or not the water is diverted into the ocean, would have any significant effect on the spread of, for instance, the Mendocino Complex of Fires currently growing east of Ukiah that at 273,664 acres has just become the second largest wildfire in the recorded history of California.
Most scientists agree that the increase in acres burned and the average size of wildfires in the United States is due to a number of factors, including climate change (high temperatures, lower relative humidity, drought), fuel buildup due to fire suppression for 100 years, and people moving into areas with continuous vegetation. This migration can increase the number of fire ignitions, and can divert the limited number of firefighters from actually suppressing a fire to protecting structures, allowing fires to grow unhindered at times.
Even the Washington Examiner, a very reliable and strong supporter of Mr. Trump, had some mild criticism about this statement by the President.
And yes, “tree clear”, can help, if by that he means reducing fuels around inhabited areas through prescribed fires and other fuel management techniques. But we will never be able to conduct enough prescribed fires to prevent blazes from becoming megafires. And increasing logging is not the answer. Large, very wide fuel breaks around subdivisions be beneficial, but it is more important for residents in the wildland-urban interface to accept the responsibility to use FireWise principles. Burning embers can cause buildings to ignite at a great distance from the main fire. Homes should be constructed with fire resistant designs and materials. Residents need to thin and/or remove flammable vegetation within 100 feet of structures.
There are many ways that a warmer climate can influence wildfires, causing them to burn more intensely. Higher temperatures can lower the relative humidity, lower the amount of moisture in the vegetation (fuel), raise the temperature of the fuel itself, and cause more powerful thunderstorms with lightning. But one factor that we don’t think about very often is that the heat can persist through the night, influencing fire behavior.
When today’s senior firefighters began their careers, they could usually count on fires “laying down” at night. The intensity and rate of spread would decline to the point where night shift personnel could more easily and safely “go direct”, constructing fireline very close to the edge of the fire…
Research projects substantial increases in area burned across western North America, with implications for land managers and policy makers.
Above: Projected change in annual area burned for the period 2010–2039, with red colors indicating areas with the greatest increase in area burned annually in wildfires, and dark blue the least.
By Susan McGinley, University of Arizona
The massive wildfires that burned in California, Oregon, Montana, Idaho, British Columbia and other parts of North America in 2017 in many cases exhibited a disturbing trend: a marked increase in the amount of area burned.
The Thomas Fire, which consumed 281,893 acres in California’s Santa Barbara and Ventura counties in December, was the largest in the state’s history. The Nazko Complex Fire in British Columbia burned more than 1 million acres, the largest ever recorded for the province.
That trend will continue in coming decades across the western U.S. and northwestern Canada, though not uniformly, according to a recent study. UA professor Don Falk and Thomas Kitzberger from the Universidad Nacional del Comahue in Argentina, who started working on the research as a visiting scholar at the UA, were co-investigators on the study that also included Thomas Swetnam from the UA and Leroy Westerling of the University of California, Merced.
While it may have been an exceptional year in some respects, Falk’s and Kitzberger’s predictions suggest that years like 2017 are likely to become more common over time. States in the interior Western U.S., in particular, may be faced with large increases in total wildfire area burned, potentially beyond anything that has been experienced in the past.
Their research paper, “Direct and indirect climate controls predict heterogeneous early-mid 21st century wildfire burned area across western and boreal North America,” was published in the journal PLOS ONE in December as the 2017 fire season was ending. The results project where the greatest increases in area burned are likely to occur across the Western U.S. and Canada in coming decades. It suggests that large fires years such as the recent ones in southern and northern California may become more common.
A Model to Measure and Project Fire Activity
“We used 34 years of climate data to calibrate area burned in 1,500 grid cells across western North America, so we could capture the different ways that seasonal climate regulates fire in different regions,” said Falk, a professor in the School of Natural Resources and the Environment in the UA College of Agriculture and Life Sciences.
The key measurement, annual area burned, is a combination of fire size, frequency and variability from year to year. Area burned does not necessarily indicate fire severity, the ecological effects in a burned area.
Taking into account geographic variation, the study data focused on fire occurrence, seasonal temperatures and snowpack. The seasonal climate variables that turned out to be driving the amount of area burned were summer temperatures during fire season, spring temperatures and rainfall, and winter temperatures. Winter and spring conditions regulate snowpack, which can delay the onset of the fire season.
The team built a statistical model for wildfire area burned in each of the grid cells studied, and then tested it with data for actual area burned since 2010 to validate their predictions. It did not project the extent of area burned beyond the mid-21st century, as climate and vegetation changes become more uncertain later in the century.
Findings for western and northern North America show that about half the states and provinces are projected to have a large increase — five or more times the current levels — in total wildfire area burned. Others may see smaller increases, indicating there is no “one-size-fits-all” model. Increases in area burned are unevenly distributed across the study area, with the strongest increases projected in the interior western region.
Heads-Up for Land Management
“Ultimately, this means that the large fire seasons of recent years, such as the one just ending, are likely to occur more frequently, affecting ecosystems, communities and public safety,” Falk said. “These will be billion-dollar fire years. We’re just not ready for fire impacts of this kind, including post-fire effects from flooding after fire.”
The total cost of the 2017 fires in California alone is projected to exceed $180 billion. This includes not only the immediate costs of firefighting, but also the much larger costs, including:
Medical and hospital costs;
Insurance losses and the costs of replacing thousands of homes and other buildings;
Lost economic productivity from the destruction of businesses;
Repair and replacement of key infrastructure such as roads, power lines and dams; and
Weeks of lost income by employees.
Across the U.S., public land managing agencies are being stretched to their limits by the current scale of wildfire. The U.S. Forest Service spends more than half of its entire budget on wildfire response, leaving little for other key elements of its mission such as recreation, ecosystem restoration, research and public education.
Knowing about future regional variation in the projected annual area burned can help land managers and policy makers prepare for the possibility of extremely large fire years. Falk pointed out that seasonal climate changes also are having the effect of making the fire season longer, so there is additional time for more acreage to burn. In years when seasonal climate drives lengthy fire seasons, fire management resources may be stretched to the limit.
“Wildfires act as a multiplier of other forces such as climate change, exposing more and more areas not only to the immediate effects of fire, but also to the resulting cascade of ecological, hydrological, economic and social consequences,” Falk said. “We hope that this research will be a wake-up call to public agencies and legislatures at all levels of government that the fire problem is not going to get any smaller in coming decades.
“If anything, we need a serious, fact-based national dialogue about how to sustain our forests and woodlands through smart management and policy.”