It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Tuesday, September 01, 2020
California is on fire. From across the Pacific, Australians watch and buckle up
California is ablaze, again. Currently, the second and third largest fires in the US state's history are burning at the same time, and are only partially controlled. Already, seven people have died and 2,144 structures are damaged—and their fire season still has months to run.
The outbreak continues a relentless trend of bigger and more destructive fires in the western US, including California' largest fire in 2018.
For Australians, the spectacle of California burning is deeply concerning. It's just months since our last fire season, concentrated in a band of eucalyptus forests along the continent's southeast coast.
There are strong parallels between the two disasters: drought, parched landscapes, high temperatures, prolonged heatwaves and dry lightning storms to set it all off. And both Australia and California are particularly vulnerable as climate change makes bushfires worse. So let's look at the fiery fate we share with those across the Pacific—and how we must all adapt.
An uncertain future
We know bushfires are being made worse by human activity and climate change. But, owing to a lack of long-term data and the complex interactions between humans, climate and fire, it's hard to predict exactly how fires will change—for example how frequent or severe they will be, how long fire seasons will last and how much land will burn.
In research published last week, we describe recent trends in fire activity and examine projections for the near future. From this, it's clear the global impact of bushfires due to human-induced climate change will intensify.
Among the areas expected to be worst hit are flammable forests in populated temperate zones, such as Australia's eastern states and California.
Climate is not the only driving factor here. Human changes to landscapes—such as urban sprawl into flammable forests—are also making fires worse.
The damage is not just environmental, but also economic. Already, Australia's last bushfire season is likely to be our most expensive natural disaster, costing around A$100 billion. And the California fires in 2017–2018 caused an estimated A$55 billion in structure losses alone.
The escalating threat demands an urgent rethink of our inadequate and inappropriate fire management strategies. These span land use planning, fuel management, communications, evacuation and firefighting capacity. All are constrained by complex administrative arrangements, limited physical and human resources, and poor budgets.
Climate change also raises the frightening scepter of a "positive feedback" loop in which climate change exacerbates fire, producing carbon dioxide emissions which worsen climate change further. This vicious cycle threatens to fundamentally alter the Earth system.
What's more, fire seasons in southern Australia and the western US increasingly overlap. As California burned last week, uncontrolled winter bushfires ripped through northern New South Wales. Australia is sending firefighters to California this time around. But as fires increasingly rage in both hemispheres simultaneously, our respective nations will have fewer firefighting resources to share.
The COVID-19 crisis is making these difficult circumstances even more challenging. For example in California, authorities are dealing with both the fires and the pandemic; the state reportedly has the highest number of infections in the US.
Firefighters must practice social distancing: that means fewer people in each vehicle and no communal eating or sleeping arrangements. And Australian firefighters will be forced into quarantine for two weeks upon their return home.
Accepting reality
In this context, recommendations handed down by the NSW bushfire inquiry last week are a landmark in how we adapt to bushfires. Central to the report is an avowed acceptance climate change is transforming bushfire management.
The report contains 76 recommendations, all accepted by the NSW government, providing creative license to rethink how we sustainably co-exist with bushfires. They include:
reforms of arrangements to manage bushfires, such as better coordination between agencies, better shared data and streamlining fuel management programs
trialing new approaches to reducing fuel loads, fighting fires and managing smoke pollution
involving Aboriginal people in managing landscapes
maintaining the safety and mental health of those on the frontline such as fire fighters, first responders and affected citizens
improving disaster management through improved training and work practices for firefighters, better communication, new technologies and investing in equipment.
The scope and scale of the recommendations underscores the huge task ahead of us.
Importantly, underpinning the recommendations is a clear commitment to analyzing which approaches work, and which do not. This accepts our current state of knowledge is partial and imperfect.
Our fire-filled futures
Co-existing with a flammable landscape is a massive and complicated task—a fact California is now being brutally reminded of. Australia can lead the way globally, but to do this requires significant investment in bushfire management to build the necessary tools, techniques and talent.
Climate change is making bushfire seasons longer, more dangerous and socially demanding. Like it or not, we have embarked on the bushfire adaptation journey, and there is no turning back.
Image taken by Suomi NPP on August 30, 2020 shows the smoke and fires in California. Credit: NOAA/NASA
NOAA/NASA's Suomi NPP satellite captured two images that tell the story about the smoke coming off the fires in California. One instrument on the provided a visible image of the smoke, while another analyzed the aerosol content within. The images were captured on August 30, 2020.
The first image captured by the Suomi NPP satellite using the VIIRS (Visible Infrared Imaging Radiometer Suite) Corrected Reflectance imagery shows a true-color image (called true-color or natural color because this combination of wavelengths is similar to what the human eye would see) of the wildfires still burning across large swaths of the state. Smoke is pouring off the fires and traveling in two different directions. Some of the smoke is traveling northeast into Nevada and as far east (in this image) as Salt Lake City, Utah, and some is traveling west into the Pacific Ocean.
The second image was captured by Suomi NPP with the OMPS Aerosol Indexer and shows not only the direction of the smoke's travel but the thickness of the aerosol layer that has moved outward from the fires. The OMPS (Ozone Mapping and Profiler Suite) Aerosol Indexer on Suomi NPP is an instrument that indicates the presence of ultraviolet-absorbing particles in the air coming from dust (desert) or, as in this case, soot from fires. The Aerosol Indexer found on the image as a scale is unitless, that is, the lowest and highest range do not relate directly to each other. It just indicates whether the scale is low or high. In this image of smoke coming off the California fires, the aerosols found were mostly in the moderate range (yellow) with some higher range areas (red). Higher concentrations can reduce visibility and impact human health. The Aerosol index is also useful for tracking long-range transport of these aerosols that move along jet streams.
Aerosols are tracked by the Suomi NPP satellite using the OMPS instrument as seen in this image of the California wildfires taken on August 30, 2020. Credits: NOAA/NASA
NASA's satellite instruments are often the first to detect wildfires burning in remote regions, and the locations of new fires are sent directly to land managers worldwide within hours of the satellite overpass. Together, NASA instruments detect actively burning fires, track the transport of smoke from fires, provide information for fire management, and map the extent of changes to ecosystems, based on the extent and severity of burn scars. NASA has a fleet of Earth-observing instruments, many of which contribute to our understanding of fire in the Earth system. Satellites in orbit around the poles provide observations of the entire planet several times per day, whereas satellites in a geostationary orbit provide coarse-resolution imagery of fires, smoke and clouds every five to 15 minutes.
NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks "right now." Actively burning fires, detected by thermal bands, are shown as red points.
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