Showing posts with label firestorm. Show all posts
Showing posts with label firestorm. Show all posts

Wednesday, January 15, 2020

The Australian firestorms: portents of a planetary future

by Andrew Glikson
Earth and climate scientist
Australian National University

Global warming and its disastrous consequences are now truly with us since the second part of 2019. At the moment a change in the weather has given parts of the country a respite from the raging fires, some of which are still burning or smoldering, waiting for another warm spell to flare up. The danger zones include the Australian Capital Territory, from where these lines are written. To date, 18.6 million hectares (186,000 square kilometers) were burnt, including native forests, native animals, homesteads and towns, and 24 people died. The firestorms betray harbingers of a planetary future, or a lack of such, under ever rising temperatures and extreme weather events inherent in fossil fuel driven global warming.

Global heating

As the atmospheric concentration of the well-mixed greenhouse gases rise (CO₂ >411.76 ppm; CH₄ >1870.5 ppb; N₂O >333 ppb plus trace greenhouse gases) land temperatures soar (NASA global sea-land mean of 1.05°C since 1880). According to Berkeley Earth global land temperatures have increased by 1.5C over the past 250 years and mean Arctic temperatures have risen by 2.5°C to 3.0°C between 1900 and 2017. According to NASA :
  1. “Extreme heatwaves will become widespread at 1.5 degrees Celsius warming. Most land regions will see more hot days, especially in the tropics.
  2. At 1.5°C about 14 percent of Earth’s population will be exposed to severe heatwaves at least once every five years, while at 2 degrees Celsius warming that number jumps to 37 percent.”
  3. “Risks from forest fires, extreme weather events and invasive species are higher at 2 degrees warming than at 1.5 degrees warming.”
  4. “Ocean warming, acidification and more intense storms will cause coral reefs to decline by 70 to 90 percent at 1.5 degrees Celsius warming, becoming all but non-existent at 2 degrees warming.”
Figure 1. The distribution of global fires. NASA.

However, bar the transient masking effects of sulphur aerosols, which according to estimates by Hansen et al. (2011) induce more than 1.0°C of cooling, global temperatures have already reached near 2.0°C (by analogy to the requirement for a patient’s body temperature to be measured before and not after aspirin has been taken). As aerosols are not homogeneously distributed, in some parts of the world temperatures have already soared to such levels. Thus the degree to which aerosols cool the earth, which depends on aerosol particle size range, has been grossly underestimated.

The rate of global warming, at ~2 to 3 ppm year and ~1.5°C in about one century, faster by an order of magnitude then geological climate catastrophe such as the PETM and the KT impact, has taken scientists by surprise, requiring a change from the term climate change to climate calamity.

The Australian firestorms

In Australia mean temperatures have risen by 1.5°C between 1910 and 2019 (Figure 2), as a combination of global warming and the ENSO conditions, as reported by the Bureau of Meteorology.

“The Indian Ocean Dipole (IOD) has returned to neutral after one of the strongest positive IOD events to impact Australia in recent history ... the IOD’s legacy of widespread warm and dry conditions during the second half of 2019 primed the Australian landscape for bushfire weather and heatwaves this summer. In the Pacific Ocean, although indicators of the El Niño–Southern Oscillation (ENSO) are neutral, the tropical ocean near and to the west of the Date Line remains warmer than average, potentially drawing some moisture away from Australia.”

Figure 2. (A) Australian mean temperature. (B) Severe fire weather. (C) Drought. (D) Driest year.
Bureau of Meteorology
The prolonged drought (Figure 2 C, D), low fuel moisture, high temperatures (Figure 2A) and warm winds emanating from the inland have rendered large parts of the Australian continent tinder dry, creating severe fire weather (Figure 2B) subject to ignition by lightning and human factors. Fires on a large scale create their own weather (see: bushfire raging in Mount Adrah and firestorm). Observations of major conflagrations, including the 2003 Canberra fires, indicate fires can form atmospheric plumes which can migrate and as hot plumes radiating toward the ground (fire tornadoes).

The underlying factor for rising temperatures and increasingly severe droughts in Australia is the polar-ward shift in climate zones (see map Oceania) as the Earth warms, estimated as approximately 56-111 km per decade, where dry hot subtropical zones encroach into temperate zones, as is also the case in South Africa and the Sahara.

Smoke signals emanating from the Australian fires are now circling around the globe (Figure 3) signaling a warning of the future state of Earth should Homo sapiens, so called, not wake up to the consequences of its actions.

Figure 3. (A) Smoke emanating from the southeastern Australian fires (January 4, 2020);
(B) smoke from the pyro-cumulonimbus clouds of the Australian fires drifting across the Pacific Ocean.
The fire clouds have lofted smoke to unusual heights in the atmosphere. The CALIPSO satellite observed smoke soaring between 15 to 19 kilometers on January 6, 2020—high enough to reach the stratosphere. NASA.

Andrew Glikson
Dr Andrew Glikson
Earth and climate scientist
Australian National University

Sunday, March 9, 2014

Dear Mr. President

Dear Mr President,

Ukraine is clearly another Western geopolitical stunt to stop Russian exports of oil and gas to Europe so they can be replaced by filthy fossil fuels from US fracking and Canadian tar sand oil. We are facing a devastating final show down with Mother Nature which is being accelerated by the filthy extraction of fossil fuels by fracking, tar sands and coal mining and continent wide oil transport in the US.

Call your troops home so they can immediately assist in assembling giant solar power stations, wind farms and converting all road and rail transport to electricity. Immediately terminate all gas fracking, tar sand oil extraction, oil transport, coal mining and all the giant subsidies paid to fossil fuel companies. This money must be solely spent on constructing renewable energy power stations and infrastructure. 

You will be held accountable by US citizens and the world if you do not stop this extreme American pollution, the fast approaching methane firestorm and our extinction by 2050.

Yours Truly,

Malcolm Peter Light (Dr)
Earth Scientist

Saturday, June 30, 2012

Earth on Fire

Two people have died in the wildfire in Colorado Springs, 347 homes have been destroyed and more than 35,000 people have been forced to evacuate their homes, in the most destructive wildfire in Colorado history, reports Reuters. The destruction surpassed the 257 homes destroyed recently by a large blaze north of Denver.
According the Wikipedia, the 2012 Colorado wildfires have now claimed 5 fatalities, over 600 homes have been destroyed and at least 202,425 acres have burned (i.e. 316.3 square miles or 819.2 square kilometers).
Below, a photo of the smoke cloud at Colorado Springs from the local Waldo Canyon fire, taken on June 26, 2012, by U.S. Air Force/Mike Kaplan.

An AP news update at USAtoday includes:
• Idaho: A fast-moving 1,000-acre wildfire in eastern Idaho that destroyed 66 homes and 29 outbuildings was expected to be contained Saturday. Some 1,000 residents were evacuated.
• Utah: More than 50 houses were destroyed.
• Montana: Authorities in eastern Montana ordered the evacuation of several communities Saturday as the Ash Creek Complex fires, which has burned more than 70 homes this week, consumed another 72 square miles. The blaze grew to 244 square miles overnight.
• Wyoming: A wind-driven wildfire in a sparsely populated area of southeastern Wyoming exploded from eight square miles to nearly 58 square miles in a single day, and an unknown number of structures have burned. About 200 structures were considered threatened.
NASA has released a map, an edited version of which is below, showing the intensity and scope of the heat wave in the western United States, with temperature anomalies reaching 12 degrees Celsius in the period of June 17 to 24, 2012. Colorado experienced the brunt of the heat wave and had eight large wildfires burning on June 28, 2012. Wyoming and Utah—other states that have seen unusually hot weather—together had nine wildfires burning.

NASA adds that this heat wave, like all extreme weather events, has its direct cause in a complex set of atmospheric conditions that produce short-term weather. However, weather occurs within the broader context of the climate, and there’s a high level of agreement among scientists that global warming has made it more likely that heat waves of this magnitude will occur.
The image on the right, edited from another NASA image, depicts the relative concentration of aerosols in the skies above the continental United States on June 26, 2012.
As the image below shows, the heat wave is moving east, with temperatures reaching extremely high values over much of the United States. The image, edited from, shows temperature predictions in both Celsius and Fahrenheit.

The image below, edited from NOAA, shows that temperatures are predicted to reach peaks on the East Coast of over 115 degrees Fahrenheit on Sunday, July 1st, 2012.

The United States isn't the only place witnessing extreme temperatures. Fires are raging in Russia, while I recently described the danger of abrupt local warming in the Arctic.
The NASA Global Fire Map below shows fires detected by satellite from June 9 to June 18, 2012.

The image below, from the Climate Emergency Institute, shows that most of the largest climate feedbacks take place at higher latitudes on the Northern Hemisphere.