Global warming, caused by 250 years of anthropogenic GHG emissions, has now reached 1.2C. It is manifesting in climate change, melting glaciers, wildfires, floods and droughts. Tipping points are imminent that are expected to accelerate warming to 3C or more before the end of the century, with unpredictable results, creating environmental, social and economic mayhem.
2 min read | Last updated 5 March 2021
What does 1+C of global warming look like? We know the answer already, because planet Earth is now ~1.2C warmer than than in preindustrial times. We are experiencing climate uncertainty, seeing environmental change and observing loss of biodiversity. This is not just an environmental catastrophe, but a human crisis.
Scientists (unlike people in the media) have been reluctant to attribute any particular weather event to climate change. As data grows, however, the evidence is becoming clearer and scientists are beginning to state with numerical confidence that is indeed climate change that is behind some of the environmental shocks and stresses we are experiencing.
Incidences of extreme heat attributable to climate change are killing people, causing 37% of heat-related deaths between 1991 and 2018 (Nature, 2021). Canada, for example, experienced day after day of record breaking temperatures approaching 50C in June 2021 and an increase in sudden deaths.
Human tolerance for extreme humid heat is much lower, with wet-bulb temperatures of 35C (the point at which we can no longer cool ourselves with shade and water) modeled to begin from the mid 21st century, but already being reported in the Persian Gulf and Indus Valley. Extreme humid heat overall has more than doubled in frequency since 1979 (The Guardian, 2021).
Even where disaster is the norm, we are being surprised. The monsoon floods in Bangladesh, 2020, were a step-change worse than normal, overwhelming well-practiced flood relief efforts in this delta nation (BBC, 2020).
Climate change isn’t just a physical threat, it’s a systemic threat to human development with the potential to slow down or reverse global progress on health, poverty, gender equality, food security and freshwater supply, among many other concerns, for a long time, centuries perhaps.
An unexpected heat shock in April 2021 in Bangladesh interrupted the reproduction cycle of rice plants, destroying 68,000 hectares, affecting the financial security of 300,000 farmers and contributing to food shortages in a nation in which one quarter of its people are already food insecure (Reuters, 2021).
Climate change is seen as a key driver behind locust swarms in Ethiopia and East Africa in 2019 and 2020, the worst in 70 years. Warmer water in the Indian Ocean is causing cyclones, which leads to the perfect conditions for their breeding (Carbon Brief, 2020). Locust swarms consume millions of tonnes of crops, impacting staple food supplies and livestock. This affects the food cycle and erodes people’s savings, pushing some into poverty. Within the affected region, there are 24 million people who are food insecure and 8 million displaced people (World Bank, 2020).
Yet, climate change denial is still an issue in some political circles, stymieing action and leaving communities under-prepared and exposed to risk. The winter freeze in Texas, 2021, revealed the vulnerability of that state’s under-maintained and isolated power grid.
What does 2C of warming look like? Over the last 40 years, Earth has been warming at a rate of 0.19C per decade. At this rate – and without accounting for tipping points – global warming would reach 2C by 2063. We barely notice a one degree rise in temperature on a typical summer’s day, but a one degree rise in the global mean temperature will cause critical ecosystem collapse, massive changes in the planet’s water geography, impacts on human health and severe stress on food systems, leading to conflict and refugeeism on a large scale.
What does 3+C of warming look like? Tipping points will make it almost certain that global warming will accelerate, hastening in consequences well before 2060 that are disturbing to contemplate.
A leaked draft of an IPCC report, not due for official publication until Feb 2022, warns that tipping points are closer than most people realise and will result in widespread disaster in the near future. Our only options are to mitigate and adapt.
‘The choices societies make now will determine whether our species thrives or simply survives as the 21st century unfolds… Transformational change to western lifestyles is essential… We must redefine our way of life and consumption.’