The climate is changing in dangerous ways, and we are responsible for most of these changes. This is not a matter of conjecture or political opinion — it is the conclusion of the overwhelming majority of climate scientists, based on solid evidence that mounts each year. Rising sea levels, extreme heat, increased incidence of floods and drought, ocean acidification and expansion of tropical diseases pose an unacceptable level of risk to our descendants. So do many other climate-related threats.
Business, scientific and technical leaders are responding to these threats by finding ways to adapt to climate change, increase our energy efficiency, and develop carbon-free energy sources. Political leaders here and abroad are creating policies that promote these advances. At the Paris climate conference in December, 195 countries adopted an historic climate agreement, whose main goal is to prevent the world’s mean temperature from rising more than 2 degrees centigrade above its pre-industrial level. This agreement was the culmination of many years of efforts by governments and citizens. The negotiators of the agreement came together despite differences in forms of government, in responsibility for past emissions of greenhouse gases and in susceptibility to future climate change.
But these efforts to reduce the risk to future generations are now being imperiled by a small yet vocal group that denies the validity of the evidence and of scientific expertise in general. Of special and immediate concern is the stated intent of the current Republican Party platform and presidential nominee Donald Trump to promote the extraction and use of the most carbon-intensive fossil fuels, to withdraw the United States from the Paris agreement and to rescind President Obama’s executive actions designed to reduce climate risk. We are deeply concerned about the serious long-term damage to our world that would result if the climate and energy policy goals of Trump and the Republican Party were to become our national policies, reversing decades of progress on energy, climate, clean air and clean water. These consequences would be borne by billions of current and future citizens of this planet.
To address this concern, we — together with 373 other members of the National Academy of Sciences — have published an open letter today drawing attention to the serious risks of climate change. We state that “the problem of human-caused climate change is real, serious, and immediate, and that this problem poses significant risks: to our ability to thrive and build a better future, to national security, to human health and food production, and to the interconnected web of living systems.” The letter also highlights the urgent need to reduce heat-trapping emissions as part of the Paris agreement.
For the United States to withdraw now from the Paris agreement would undermine the world’s ability to deal with climate change, diminish U.S. credibility internationally, and hobble U.S. economic competitiveness in developing and marketing clean energy sources. But where there is risk, there is also opportunity for creative problem solving. As the letter notes, “Nations that find innovative ways of decarbonizing energy systems and sequestering CO2 will be the economic leaders of the 21st century.”
We should not turn the clock back by regarding scientific ignorance as a virtue, or by embracing business-as-usual energy policies. It’s time to unleash the renewable and limitless power of the mind, and to accelerate efforts to develop and implement clean energy sources. This is the leadership we need, and this is the only kind of leadership that will reduce the worst climate change risks to our children while presenting them with new and exciting economic opportunities.