The public debate only highlights the negative effects of increasing carbon dioxide in the atmosphere. But there are also positive impacts. By Bjorn Lomborg, director of the Copenhagen Consensus Center and assistant professor at Copenhagen Business School
A recent study in the journal Nature has revealed how increasing carbon dioxide (CO₂) has made the Earth greener over the last three decades. Because CO₂ acts as a fertilizer, half of the vegetated land is becoming greener today. This should be, to say the least, pleasing. But instead, according to BBC statements, we should not be less concerned about global warming and threats such as the melting of glaciers and the intensification of tropical storms. And several major media outlets did not mention this study.
Our climate debate is unbalanced. While there is considerable room for discussion about the causes of climate change, any positive mention of it is frowned upon. It has been known for decades that increasing CO₂ and precipitation would make the planet greener – it is likely that by the end of this century, the planet’s biomass will increase by 40%.
Fewer deaths from cold
Similarly, we know that the rate of cold-related deaths is much higher than that due to heat. The largest study of deaths from cold and heat, published last year by Lancet magazine, looked at more than 74 million deaths worldwide, from Nordic countries like Sweden to tropical countries like Thailand. According to researchers, heat accounts for 0.5% of these deaths compared with 7% for cold-related deaths.
As global warming increases temperatures, deaths from heat waves will increase – a point made by activists such as the former executive secretary of the United Nations Framework Convention on Climate Change (UNFCCC), Christiana Figueres. What she did not mention is that there will be fewer deaths caused by the cold. A study in England and Wales shows that heat waves cause 1500 deaths per year compared to 32 000 deaths caused by cold weather. By the 2080s, the increase in heat waves will cause about 5,000 deaths in a comparable population sample. On the other hand, there will be 10,000 less “cold-related deaths”, which would result in a total of 6,500 fewer deaths per year.
Mentioning only the negative aspects distorts and degrades the political debate. Every reasonable person is able to recognize the positive and negative aspects of the political proposals of the different parties. To insist that there are only negative aspects on all sides would be tantamount to extremist partisanship.
The world becomes less vulnerable as it grows: a storm that hit Florida killed far fewer people compared to a similar situation in Guatemala where tens of thousands of deaths were recorded. And the number of climate-related deaths has decreased from half a million deaths a year in the 1920s to less than 25,000 deaths a year in the year 2010. A recent study conducted by Nature magazine, predicting a intensification of storms linked to global warming, has shown that the resulting economic damage will be reduced by half, from 0.04% to 0.02% of GDP, insofar as the impacts of the intensification of storms will be offset by the increase of prosperity.
See the positive sides
If the climate debate includes both negative and positive aspects, we will have a better understanding of our options. This is what the world of the climate economy does: take the negative sides (like rising sea levels and increasing heat deaths) and the positive sides (a greener planet) , a reduction in cold-related deaths). An economic approach to the climate has shown that today – contrary to the massive persistence of alarmists to point the negative historical – global warming caused as much damage as profits. Over time, the problem of global warming has become clearer: according to the projections of the Intergovernmental Panel on Climate Change (IPCC), the damage caused by global warming by 2070 would be equivalent to 2% of World GDP. It’s certainly not a trivial cost, but it’s not the end of the world either. This represents perhaps half the social cost of alcoholism today.
Seek effective policies
This suggests that a policy that could eradicate global warming for a cost equivalent to 1% of GDP would be a good option. Unfortunately, this is not relevant. The Paris Treaty on Climate will cost about 2% of global GDP and solve less than a tenth of the problem. More ambitious and less efficient climate policies cost at least 6% of GDP annually. Wind and solar, which currently cover less than 0.5% of the planet’s energy needs, cost 12 times more than the benefits they bring. Electric cars generate a climate benefit of perhaps one-thousandth of the huge public subsidies allocated to them. Biofuels are simply very expensive, while they increase carbon emissions.
If we focus the climate debate on determining the positive and negative sides, and focus our attention on the costs and benefits of policies – essentially addressing this challenge like any other political agenda – the inadequacy of many of the climate policies adopted currently will seem obvious to us. It is not surprising that activists do not want this kind of dialogue.