Man-made climate change is dangerous, that much is clear. With so much at stake, it seems remarkable that so little progress has been made on the issue; there are complex social factors underlying the drive to take action, or the lack thereof. A new study published in Nature identifies another aspect of life that will be severely affected by man-made climate change; namely, the world’s economies will take a heavy hit before the end of the century if we continue to pump greenhouse gases into the atmosphere with reckless abandon.
A small team of economists tracked gross domestic product (GDP) values – a measure of a nation’s wealth – with average annual temperatures across time. They found that economic growth peaks at an annual average temperature of around 13 degrees Celsius (55 degrees Fahrenheit); if the temperature is lowered or raised, GDP begins to gradually decrease. The greater the divergence from this temperature, the more rapidly the GDP drops. Any temperature below 0 degrees Celsius (32 degrees Fahrenheit) or above 25 degrees Celsius (77 degrees Fahrenheit) causes a dramatic collapse in GDP.
The link between GDP and temperature is not as direct as it may initially seem, however. “Culture matters, institutions matter, policy choices matter,” Marshall Burke, an economist at Stanford University and co-author of the study, told Wired. “What we do find is looking historically, temperature matters a lot.”
The economists then used this historical data to make projections for various parts of the world, revealing the complex effects that increased global temperatures will have on regional economies. The poorest countries, often nearest the equator, will see their high temperatures become even higher. Beyond certain temperatures, humans cannot work efficiently, physically or mentally. Agriculture cannot operate under extremely high temperatures, so food generation will tumble to new lows. Rising sea levels and more powerful storms fueled by hotter oceans will cause far more damage to infrastructure than ever before.
Temperate northern European nations will possibly benefit in the short-term, as an increasing global temperature will push their average nearer to the 13 degrees Celsius “sweet spot”. The United States and China, the world’s two largest carbon emitters, will suffer, despite having extremely high GDPs. Their countries cover so much land across many latitudes, leaving them vulnerable to climatic extremes.
Overall, the global economy will be negatively affected. By the end of the century, the economic production of the world will fall by roughly 23% if we continue changing the climate as we are at present, the study suggests.
The habitability of the world’s oceans and the forests are under assault; rivers are drying up, and even some of our own cities are already doomed to be consumed by the rising seas, yet global action against climate change is relatively slow. So studies like this are important: many vested interests are driven purely by monetary gain, and the thought of losing out on cashing in will be, for many nations and industries, a reality they would rather try to prevent.
It’s the world’s wealthiest nations, not the just the poorest, that will find their wallets considerably lighter by 2100 otherwise.
[H/T: Wired]