According to the UNHCR, since 2008 an estimated 22.5 million people have been displaced by climate or weather-related events. According to researchers from the World Health Organization (WHO) and the University of Wisconsin global warming is already responsible for some 150,000 deaths each year around the world. In 2014, the World Health Organization (WHO) estimated that climate change would lead to about 250,000 additional deaths each year between 2030 and 2050, from factors such as malnutrition, heat stress and malaria.
The climate crisis constitutes the greatest existential threat humanity has ever faced and the biggest assault nature has suffered since 66 million years ago. From 1870 to 2014, cumulative carbon emissions totaled about 545 GtC. Emissions have been absorbed by the atmosphere (approx. 230 GtC or 42%), ocean (approx. 155 GtC or 28%) and land (approx. 160 GtC or 29%). The future burning of the known fossil fuel reserve will transfer an additional >3000 GtC to the atmosphere and threatens to render large parts of the Earth uninhabitable. Yet, bar lip service and non-binding agreements, world governments are now presiding over the demise of much of the global biosphere and of civilization. As the planet keeps warming and the powers that be are spending trillions of dollars on so-called “defense” and murderous wars, tragically people and nature suffer.
Every week the internet reports newly discovered and exploited coal, oil and gas fields. Just as often it reports cyclones, floods and fires. The two are intrinsically linked. Whereas any single extreme weather event may not be related to global warming, the trippling of the incidence of extreme weather events heralds the rising energy and warming of the planetary system. This takes us away from conditions that allowed humans to flourish in the recent Neolithic age, as contrasted with earlier conditions in which stone age people had to struggle to survive.
By 2018 the carbon content of the atmosphere exceeded 750 billion tons (GtC) as compared to the pre-industrial atmospheric composition of ~620 GtC, representing the largest transfer of carbon from the Earth to the atmosphere since 56 million years ago. Over the last quarter century carbon emissions have risen by almost 63 percent (1990 – 22.6 MtCO2/year; 2005 – 30 MtCO2/year; 2017 – 37 MtCO2/year; 2017/1990 – +163.5%). Coal production in Australia increased 13.6% between 2005 and 2010. In 2016 Australia was the fourth-highest producer with 6.9% of global production (503 MtC out of 7,269 MtC total) and was the biggest net exporter of coal, with 32% of global exports (389 MtC out of 1213 MtC total).
As a consequence of global carbon emissions, by 2018 mean global temperatures reached +0.98C above pre-industrial conditions and rose further by more than +0.5C over the continents, for example reaching +2.2C in Mongolia. The temporary temperature lowering effect of human-emitted aerosols in the atmosphere potentially accounts for a latent additional temperature rise of between 0.5 and 1.0C (as was manifested for example when jet flights contrails were discontinued on 9/11).
In coastal regions and islands the rise in temperature is driving increasingly intense cyclones and flood events, such as hit the Caribbean islands, southeastern Texas, Florida, Mississippi, southwest Pacific islands, the Philippines, Kerala, Mozambique, Zimbabwe, Japan, Queensland, and other regions.
In terms of the effects of global warming on human life, a quantitative risk assessment by the World Health Organization (WHO) suggests additional climate change-related deaths for the year 2030 would total 241,000 people (38,000 due to heat exposure in elderly people, 48,000 due to diarrhea, 60,000 due to malaria, and 95,000 due to childhood under-nutrition).
A changing climate not only affects agriculture but also leads to greater food spoilage from heat, leading to diarrheal illnesses and hunger that caused around 310,000 deaths in 2010. Heat and cold illnesses, malarial and vector-borne diseases, meningitis and environmental disasters account for the rest of the almost 700,000 deaths attributable to these direct climate impacts. Pollution, indoor smoke, and occupational hazards related to the carbon economy cause 5 million deaths through ailments like heart disease, skin and lung cancer.
The melting of the polar ice sheets, where warming takes place at twice the rate as the rest of the Earth, heralds a further fundamental global climate shift, rendering even larger parts of the land subject to extreme weather events such as those already affecting island chains and coast regions, costing the lives of tens of millions.
Life on Earth is controlled by the presence of water, insolation, the composition of the atmosphere and oceans, asteroid impacts and large volcanic eruptions. Cyclic and abrupt changes in these factors have affected the climate over billions of years. Sharp rises in atmospheric greenhouse gas concentrations, such as occurred about 66 and 56 million years ago and at present, have and are leading to major crises in nature. The current rise in atmospheric greenhouse gas concentration, combining the effects of CO2, methane and nitric oxide, is now tracking toward 500 ppm CO2 equivalent, the stability threshold of the large ice sheets. The consequent rise in mean global temperature by 3 to 4 degrees Celsius over a period as short as a century represents the highest recorded in geological history, posing an existential threat for most species and for civilization. Current manifestations include a growing spate of extreme cyclones, floods, droughts and fires killing large number of people. Inexplicably business as usual persists among the political classes, chief executives and the media, expressing a plethora of half-truths and lies, defying the original definition of the species as “sapiens”.
Andrew Glikson graduated at the University of Western Australia in 1968, conducted extensive geological research in Australia and overseas, studied mass extinction events and the effects of extreme events on climate and human evolution.