As is customary now, whenever tragedy strikes, the internet buzzes
with articles blaming climate change. Hijacking the tragic Australia’s
bushfires was to be expected. For instance, Microsoft’s MSN website just published
“Climate
deniers are cooking themselves — and everyone else”. They wrote, “Fires get
worse when things are hot, dry, and windy, and climate change has provided all
of those conditions in abundance. The continent has warmed by about 2
degrees Fahrenheit (a bit over 1 degree Celsius) since the 1970s, and in
keeping with the predictions of climate models, Australia has experienced
steadily worse droughts and heat waves over the last 30 years. The
current drought may end up being the worst in history — this spring
was the driest ever recorded on the continent, and back on December
18 it set a new record for the hottest day ever measured with an average
temperature across the entire country of 105.6 degrees.”
How truthful is MSN? Indeed, Australia is experiencing hot
dry summer weather. The map below (Figure 1) shows that most of Australia experienced
temperatures far above average for December 18, 2019. But curiously the east
and west coasts, as well as northern Australia were experiencing temperatures several
degrees below normal. If global warming was driving the extreme wildfire
season, we would expect the worse fires to be located where temperatures were
warmest. But as the map of wildfires reveals (Figure 2), the warmest regions
had the least wildfires, while the most fires were happening in the cooler
regions. Averaging Australia’s temperatures to deceptively blame global warming
for the wildfires only obscures the regional temperature effects.
Figure 1 Australia December 18, 2019 temperature anomalies. |
Figure 2 Locations of Australia's 2019/2020 bushfires. https://www.newsweek.com/australia-wildfire-map-update-bushfires-sydney-new-south-wales-1480207 |
MSN’s climate fearmongers dishonestly claim “Australia has
experienced steadily worse droughts.” Climate
fearmongers argue warmer temperatures will evaporate surface moisture more
quickly and exacerbate droughts. But they have the tail wagging the dog. Australia’s
Bureau of Meteorology’s illustration (Figure 3) shows the 1920s and 30s had experienced
much worse droughts than recent decades.
Furthermore, during periods of low precipitation, drought conditions CAUSE
higher temperatures. Without normal soil moisture to evaporate, solar radiation
is no longer consumed as latent heat of evaporation, but instead, rapidly
raises land temperatures.
Figure 3 Australia average annual precipitation from 1900-2018. http://www.bom.gov.au/climate/history/rainfall/?fbclid=IwAR2fUMmwkIr9NvJaxaNWpB1h8vaP8aNP9Aim27yGJ6r8xxcHc-lmuxdIFJg |
The greatest 2019/2020 burned area is concentrated along the eastern coast in the states of New South Wales and Victoria. Both areas are known for habitat that is very susceptible to extreme fire danger. But are the recent fires worse than ever? History says NO! In February 1851, the Black Thursday bushfires incinerated about five million hectares (about 1,900 square miles). Around 12 lives, one million sheep and thousands of cattle were lost. Temperatures reached record extremes of about 47°C (117°F) in the shade. In contrast, MSN attributes the 2019 December fires to a misleading average temperature across the whole country of 40.6°C (105°F).
If temperature and precipitation cannot be attributed to the
increasing trend in wildfires, what other factors should be considered? As in
California, Australia has experienced a tremendous increase in human ignitions. Arson
is a huge problem. As government investigations reveal (Figure 4), deliberately
set fires account for 64% of all ignitions, while only 11% of all wildfires are
due to natural lightning ignitions.
Figure 4 Cause of wildfire ignitions. https://aic.gov.au/publications/bfab/bfab021?fbclid=IwAR0QhXu6Wpu_z4d1VPDTxkJoANeck7oZCqheKbf2z8Z7T2XIC646xHbDTbY |
Furthermore to the north, tropical and subtropical regions
are being invaded
by foreign grasses that are easily ignited and provide greater surface fuel
continuity allowing fires to spread over greater areas. Likewise, humans must manage
forest floor fuel loads. The easiest solution is prescribed burns. However,
that solution is often resisted because people do not want to experience the accompanying
smoke. But until prescribed burns are allowed to be judiciously applied, the
public becomes increasingly vulnerable to larger more severe wildfires as endured
in 2019.
Bad analyses always promote bad remedies! Blaming rising CO2
concentrations and global warming is only misdirecting real efforts to minimize
wildfire destruction. What Australia and the world needs to address is 1) human
ignitions, 2) invasive
grasses and 3) fire suppression that allows surface fuels to accumulate and
enable large intense and destructive fires to wreak havoc like never before!
Jim Steele is director emeritus of the Sierra Nevada Field Campus, SFSU and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism.
Contact: naturalclimatechange@earthlink.net