As global emissions keep growing and the climate crisis intensifies, Professor Stefan Rahmstorf of the renowned Potsdam Institute for Climate Impact Research has a sobering reminder: when we talk about global warming of 2-3°C, the reality on land, where we live and grow our food, will be much worse. The heat absorption capacities of land and oceans are different. As a result, land areas are warming at double the rate of the global average. This means that if global temperatures rise by 2-3°C which is sadly emerging as a very likely best-case scenario, land temperatures where we live and farm could increase by 4-6°C or more. That will create a very dangerous world.
Why Does Land Warm Faster?
The ocean absorbs heat more effectively than land, acting as a buffer that mitigates the rise in global average temperatures. In contrast, land has a lower heat capacity, meaning it heats up faster and disburses heat less effectively. This results in significantly higher warming over land compared to oceans. According to Rahmstorf's analysis, this has already been observed and is projected to worsen in the coming decades.
Impacts on Cities and Food Security
For cities, a 4-6°C increase will mean intense and prolonged heatwaves, making many urban areas increasingly uninhabitable without substantial and expensive adaptation measures. Urban heat islands, where concrete and asphalt trap and radiate heat, will exacerbate this, leading to rising mortality rates during extreme heat events, infrastructure failures, and significant economic disruptions.
For agriculture, 4-6°C of warming presents a dire threat to global food security. Higher temperatures affect crops’ and animals’ abilities to grow and metabolise. In a nutshell, they wilt and die. This level of heat will also have major impacts on water availability, it will significantly reduce crop yields, and it will increase the frequency of extreme weather events like droughts and floods. All of this will jeopardise global food supply. Many staple crops, including wheat and maize, are sensitive to even small increases in temperature. 4-6°C of warming will cause agricultural productivity to collapse in many regions.
Need for Urgent Action
Rahmstorf’s research underlines the urgent need for an end to delay and greenwashing by governments and corporations. We need ambitious climate action. Reducing the global temperature rise to below 2°C is essential to avoid the catastrophic outcomes of amplified warming on land. Even 2°C won't be pretty. But without swift and comprehensive climate action, cities and food systems will face unprecedented challenges. This will threaten the livelihoods and well-being of billions of people globally. Australia won't be immune.
The time to act is now, before these dire predictions become our everyday reality. With an election on the horizon, every Australian’s vote will count when it comes to climate. That’s why I will only be giving my vote to candidates that are serious about climate action.
Comments