by Professor Kenneth Hayes
We are in a moment of awakening about the climate crisis. As of today, there are 334 towns containing a total population of 33 million people that have passed a climate emergency declaration. Most of these declarations have been passed since the Intergovernmental Panel on Climate Change issued a stern report in October 2018 summarizing the difference in climate impacts between an increase in Earth’s average surface temperature of 1.5 Celsius versus 2.0 Celsius relative to the average surface temperature at the start of the industrial revolution. The warming trend over the past several decades is very clear: On our current trajectory Earth’s temperature will cross 1.5 C warming around 2040 and 2.0 C warming around 2060. The consequences to humans and other life on the planet of 2.0 C warming are severe.
The first three Mondays in February, I presented three lectures on climate change. The first lecture was on the physics that determines the average surface temperature of planets with and without atmospheres. The physics that determines the temperature of planets without atmospheres is very simple: a one-line formula correctly predicts the average temperature of planets and moons in the solar system that lack atmospheres. The atmospheric greenhouse effect increases the average surface temperature of planets that have greenhouse gases in their atmosphere. Currently, the greenhouse effect on Earth increases the average planet surface temperature by 33 C (60 F) from what it would be if there was no atmosphere, and this is why the oceans are not frozen. The second lecture presented some of the consequences of the global warming occurring on Earth due to our emissions of greenhouse gases produced primarily by the burning of fossil fuels. Our emissions have increased the concentration of carbon dioxide in the atmosphere by 46 percent since the start of the industrial revolution. The third lecture discussed possible solutions.
The climate problem is very well understood. Currently there are a large set of solutions to the problem that could be implemented. The essential challenge is getting people to act. Tragically, there is a vast amount of disinformation in the media and on the Internet about the climate issue. The people who have the most to lose by a conversion of the world’s energy systems from fossil fuels to renewable energy understand that the most effective way of slowing this conversion is to spread doubt about the science and the consequences of global warming. One of the main goals of my three lectures was to provide enough knowledge of the physics — including a demonstration of the striking effectiveness of carbon dioxide to trap infrared radiation — so that anyone who followed the lectures would understand what is going on and would thus be insulated from the massive amount of disinformation on the climate issue.
The most important things you can do to work towards a solution are to educate yourself and talk to others about the climate problem. Vote for politicians who understand the problem and who are committed to working towards a solution. Learn about your carbon footprint, and take action to reduce it. I have included in my lecture slides many links to web resources at various levels from the most introductory to recently published peer-reviewed scientific papers. These links are a good place to start expanding your understanding. If you wish to get access to the PowerPoint slides I presented in these lectures, please contact me.