Climate Change Kills 5 Million People Every Year


A report released earlier this year from the climate change watch group DARA estimates that the deaths related to climate change and its chief driver, fossil fuels, were roughly 5 million in 2010. That number makes climate change one of the leading causes of death in the world; for comparison, cancer causes about 7.6 million deaths per year.

These deaths are caused by a variety of factors related to climate and carbon. A changing climate not only makes agriculture less productive in many areas of the world, decreasing access to food, but also leads to greater food spoilage from heat; these effects alone lead 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 the rest of those 5 million deaths through ailments like skin and lung cancer.

The vast majority of these impacts are felt in developing countries — those areas least prepared to deal with climate change. A whopping 90% of the mortality identified in the report comes from developing countries. China and India top the list for climate and carbon-related fatalities, at 1.5 and 1 million deaths in 2010, respectively. The majority of those deaths were a result of pollution from the carbon economy, highlighting the need to switch to cleaner fuels in these regions, and for more stringent pollution standards.

Eighty-three percent of the deaths due to climate-related factors happened in low-carbon-emitting developing countries — the places least responsible for climate change. Meningitis due to rising humidity and irregular weather, crop failures due to heat and water stress, and food and water spoilage contribute to rising death tolls in these places. Improving quality of life in these places, especially as the climate changes, is of paramount importance.

The DARA report also estimates the cost, as a percentage of GDP, of climate change and the carbon economy. Overall, they are estimated at around 1.6% of the global economy in 2010, though again these effects are felt predominately in the developing world. The Least Developed Countries lost on average 7% of their GDP to climate and carbon economy impacts. These GDP losses come from diverse factors (see here for the full DARA methodology), including costs of lost crop productivity, sea level rise costs, costs of replacing water losses due to drying climate (which will be quite large, especially on a global scale).

These impacts are only expected to worsen as the climate change we have already committed to kicks in, which is estimated at around 1° F – this may not sound like much, but as a global, annual average it hides much larger swings in temperature that will happen on smaller regional and temporal scales. DARA estimates that by 2030, the deaths per year due to climate and the carbon economy will rise to 6 million. These figures imply that by the end of the next decade this crisis will be responsible for 100 million deaths! As well, economic impacts will grow to a staggering 3.2% of world GDP by 2030 (and will only further increase from then).

Given these figures, even if they serve only as a ballpark for the future numbers, taking action on climate change makes good sense. As the economic costs of climate change grow, taking action to mitigate it will seem, comparatively, cheaper and cheaper. The Stern Review on the Economics of Climate Change, in 2006 estimated the cost of avoiding the worst climate impacts to be around 1% of GDP per year — no small chunk of change, but definitely smaller than 3.2%. Although that Review was controversial for its use of discount rates, it still provides a useful ballpark number; this estimate shows that the costs of avoiding climate change are likely smaller than the costs of climate changes’ impacts.

Besides this economic sense, avoiding these deaths makes moral sense. The improvements needed to avoid the deaths due to climate change and fossil fuels, especially in the developing world, are many of the same ones already being sought to improve quality of life in these countries. The Millennium Development Goals for poverty reduction already cover areas related to hunger and health, key drivers of climate-related deaths. Such actions, as well as investment in clean and renewable energy and pollution controls, seems like a very urgent win-win in by the calculating light of these new figures.