By Dr Andrew Glikson, Earth and Paleoclimate scientist, Australian National University
When Hurricane Harvey hit the United States in August 2017, it was called a “500-year event” and referred to as “historic” and “unprecedented”. The press has a short memory. In reality, it was Houston’s third such flooding event in as many years.
As extreme hurricanes and extensive wildfires proliferate around the globe, when journalists – including journalists of public broadcasters such as the ABC – report about these events, the words “climate change” are rare or have almost disappeared from much of the mainstream media.
It is commonly stated that single extreme weather events do not necessarily represent the effect of climate change, so the journalists tend to use statements such as “once in 50 years” or “once in 100 years” rather than mentioning the ‘c-word’.
Three recent examples:
“Mt Krauss received 95mm in 2 hours this morning, a rate only expected once in 100 years!”
» Bureau of Meteorology – 27 January 2018:
“The state’s leading independent weather forecasters are predicting a downpouring of rain around the Channel Country that could ‘rival anything during the past 44 years’.”
» The Advertiser – 2 March 2018:
Major rain event threatens worst floods in Queensland since 1974
“Heavy snowfalls and life-threatening sub-zero temperatures across Europe have been described as the worst “in a generation”. The death toll in Europe is at least 46.”
» The New Daily – 2 March 2018:
Met Office issues ‘red warning’
More extreme weather
Over the last few decades, however, extreme weather events have occurred far more frequently. The rise in meteorological and hydrological events is recorded by the Munich-Re Institute, as shown in this figure:
The International Panel on Climate Change (IPCC) stated in 2012:
“Models project substantial warming in temperature extremes by the end of the 21st century. It is virtually certain that increases in the frequency and magnitude of warm daily temperature extremes and decreases in cold extremes will occur in the 21st century on the global scale. It is very likely that the length, frequency and/or intensity of warm spells, or heat waves, will increase over most land areas.”
In addition increased evaporation in the warming Arctic and weakening of the polar boundary result in penetration of snow storms into the Eurasian and North American continents.
“A 1-in-20 year hottest day is likely to become a 1-in-2 year event by the end of the 21st century in most regions, except in the high latitudes of the northern hemisphere, where it is likely to become a 1-in-5 year event.”
Many reports in international journals confirm the relation between carbon emissions, global warming and extreme weather events. This was the case with the American hurricane Harvey, reported Reuters, New Statesman, The Guardian, The Atlantic, and Politico Magazine, among others.
There is of course no lack of claims on climate denial websites that the extreme weather events have no relation to the global warming, which now is about +1.5 degrees Celsius higher than 250 year ago. During the American hurricane disaster, such claims were exemplified by the Global Warming Policy Foundation (GWPF), Dr Roy Spencer, and reported by The Slot.
More heat and fire
The rise in land temperatures results in an increased frequency and intensity of heat waves and fires, at a rate about two to three fold during 1980–2012, according to Munich Re-Insurance 2012.
Up-to-date evidence for developments in the atmosphere is presented by NASA. The physics of this trend are elementary: as global temperatures rise, evaporation from the oceans increases, forming migrating cyclonic cells. The moisture needs to be dumped somewhere. Lightning strikes ignite forest fires. As temperatures rise, hot air plumes migrate from desert regions into cultivated and forest regions, creating conditions for wildfires.
The occurrence of heat waves, droughts and fires in tropical and semitropical parts of the world and of cold fronts and snow storms in high to mid-latitudes of the northern hemisphere represents an increased climate polarity and disruption.
According to Rahmstorf and Coumou (2011) (‘Increase of extreme events in a warming world’),
“We find that the number of record-breaking events increases approximately in proportion to the ratio of warming trend to short-term standard deviation. Short-term variability thus decreases the number of heat extremes, whereas a climatic warming increases it.”
Similar anomalies were reported by James Hansen et al. in 2012, stating:
“The distribution of seasonal mean temperature anomalies has shifted toward higher temperatures and the range of anomalies has increased. An important change is the emergence of a category of summertime extremely hot outliers, more than three standard deviations (3σ) warmer than the climatology of the 1951–1980 base period. This hot extreme, which covered much less than 1 per cent of Earth’s surface during the base period, now typically covers about 10 per cent of the land area.”
Science ignored by politicians
None of the above appears to trouble law makers in the most heavily carbon polluting nations, including Australia, in the process of opening coal mega-mines and exporting more than twice its domestic carbon consumption, where the total carbon emission from combined domestic use and export is one of the highest in the world.
When in 2017 a lump of coal was presented in the Australian Parliament to the cheers of conservative MPs, no doubts could remain regarding their stance on global warming, covered with a thin fig leaf of the non-committal Paris agreement.
One wonders whether the Prime Minister would now be willing to reiterate his statement of 2010:
“Now our response to climate change must be guided by science. The science tells us that we have already exceeded the safe upper limit for atmospheric carbon dioxide. We are as humans conducting a massive science experiment with this planet. It’s the only planet we’ve got.”
Some hopes has lingered though regarding the Labor Party’s priorities ever since it was elected in 2007 under the slogan of “the greatest moral challenge of our time” but these too have now been dashed when Labor leader Bill Shorten told reporters that if the Adani coal mine project cleared all the regulatory hurdles, then “all well and good”.
While the major parties differ regarding the Renewable Energy Target (RET), with the Coalition proposing a 23 percent target and Labor aiming at a 50 percent target, both have since withdrawn from these targets. The conservatives replaced the RET with a National Energy Guarantee (NEG), while Labor appears to retreat from their 2030 target.
Export of climate disruption
Neither of the major parties mention the open secret of Australia’s coal and gas exports.
In 2016 Australia’s thermal and metallurgic coal production reached 555 million tonnes (~555 x 3.6 x 0.8 = ~1,600 million ton CO2), including export of 485 million tonnes coal, (~485 x 3.6 x 0.8 CO2 = ~1,400 million ton CO2), according to the Australian Government’s Department of Industry.
As associate professor Peter Christoff from University of Melbourne stated in The Conversation, “Specifically, Labor’s national energy export policy undermines and overwhelms any benefits from its domestic climate policy efforts.”
If the Adani project goes ahead as planned, this coal mine alone will see up to 2.3 billion tonnes of coal extracted from an area five times the size of Sydney Harbour over 60 years.
A close corollary to the Australian situation is Norway, which aims at almost total renewable domestic energy target, while continuing with extensive oil drilling program in the Barents Sea and elsewhere.
As CO2 disperses through the global atmosphere, including Australia and Norway, such double counting, while politically expedient, can only enhance the climate calamity currently underway, including the increased frequency and intensity of extreme weather events around the world.
This article is based on extracts from two separate articles by Andrew Glikson.
Dr Andrew Yoram Glikson is an Earth and Paleoclimate scientist at Australian National University, affiliated with the ANU Climate Change Institute.
Glikson has written and co-written numerous books, most recently: ‘The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth’ (2017), ‘Climate, Fire and Human Evolution’ (2016), and ‘Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon’ (2014).
“We’re simply talking about the very life support system of this planet.”
~ Hans Joachim Schellnhuber, chief climate advisor to the German Government, director of Potsdam Institute for Climate Impact Research, in 2009, before the UN Climate Summit in Copenhagen
Climate change made Hurricane Harvey wetter. Here’s how we know
“We all remember the chorus around 2017’s disastrous hurricane season: “Don’t politicize this! We don’t know if it’s climate change!” Well, thanks to a new field of scientific study, we actually do know if an extreme weather event was made possible by climate change. Get to know … extreme weather attribution!”
The video was published by the American magazine Grist on YouTube.com on 2 March 2018.
» Article in Grist:
Climate change made Hurricane Harvey wetter. Here’s how we know
» USA Today – 16 March 2018:
Greenpeace chief finds hope amid devastating climate change impacts
“Jennifer Morgan, executive director of Greenpeace International, finds hope in new scientific studies that more precisely link devastating storms, fires and floods to climate change.”
— Kate Mackenzie (@kmac) March 19, 2018
Australian bushfires and climate change
“We are the land of droughts and flooding rains, we’re the land of bushfires. Nature hurls her worst at Australians – always has and always will. You can’t attribute any particular event, whether it’s a flood or fire or a drought or a storm – to climate change.”
~ Malcolm Turnbull, Prime Minister of Australia
» 9News – 19 March 2018:
Malcolm Turnbull ‘disappointed’ the Greens linked Tathra blaze to climate change
Disappointing to see @TurnbullMalcolm not up-to-date on attribution science. Yes, we can't say climate change caused these events but we can look at how it's changing their intensity and frequency https://t.co/ZgkkkXkuh2
— Andrew King (@AndrewKingClim) March 19, 2018
“Disappointing to see Malcolm Turnbull not up-to-date on attribution science. Yes, we can’t say climate change caused these events but we can look at how it’s changing their intensity and frequency…”
~ Andrew King