There are a very few die-hard climate change deniers left but even most of the deniers have given up on saying the earth isn't warming. In the face of new high-temperature records set nearly every year for a decade, the remaining deniers nevertheless concentrate on denying that the warming of the planet is caused by human activity.
What does it matter?
Now the few remaining deniers just pretend climate change isn’t anthropogenic (caused by human action). But just looking at melting glaciers and ocean temperature records tells everyone the temperature is increasing.
And what does it matter if people are the major cause of climate change or even if it is due to mostly due to natural causes? The fact is that people can control the amount of CO2 they put into the atmosphere. Therefore they can help reduce the amount of greenhouse gases by reducing human contribution.
Humans are responsible for adding 40 billion tons of CO2 each year and that is simple to calculate, not subject to scientific or even political debate. We know how much coal, oil, and natural gas are burned each year.
How much damage does warm weather cause?
People concerned with climate change mainly focus on the rise in sea levels which is projected to be between a few feet and 30 meters (Hansen) by the end of the century but whether Sea Level increases a little or a lot there is an even more important consideration which is often ignored, perhaps because it is just too frightening.
Proceedings of the National Academy of Sciences has just published a report on the impact of even small changes in global temperatures saying that each 1°C rise in global temperature will heavily impact food production - as much as 5 percent of the most critical foods.
Everyone knows temperature influences plant growth but while we home gardeners look for July and August heat to mature tomatoes, grain growers in the U.S.
mid-west already have such hot weather during the summer that they have trouble keeping the fields irrigated. When you combine that with the fast dropping irrigation water table (Ogallala aquifer) in the midwest, and the outlook for drought caused by climate change, the prospect of widespread starvation by the end of the century is very frightening
Study results
Based on four analytical methods the different studies all looked at how corn, wheat, soybeans, and rice yields are affected by temperature changes.
Those four crops are most important because they supply nearly ⅔ of the caloric input for the world’s people.
The report says, in part, “Each degree-Celsius increase in global mean temperature would, on average, reduce global yields of wheat by 6.0%, rice by 3.2%, maize by 7.4%, and soybean by 3.1%”
People in affluent countries who eat a lot of protein may not realize how critical those foods are, but consider the last meal you ate which didn’t involve some kind of bread? From hamburgers or fillet-of-fish sandwiches to pizza and tacos, even fast food relies heavily on wheat and/or corn.
But more important for people in the U.S. and other advanced countries is the fact that beef, chicken, and pork production all rely heavily on corn for feed.
From food loss to drought to sea level
The climate crisis will hit the entire world in a triad. First, drought and temperature rise will reduce food production and nothing causes riots and revolutions faster than three days without food.
Second, as sea level rises even a foot or two many major cities will be flooded out at least to the extent that their water will be polluted and sewer systems won’t be able to handle the saltwater flooding into the sewers.
Third, widespread droughts will cause increasing shortages of potable water and lack of water is second only to lack of food in causing people to demand a change of government.
1.2 billion people already lack daily access to clean drinking water.
War
The Pentagon sees climate change as possibly the most dangerous event in the world because it will inevitably lead to wars as people flee droughts, starvation, and sea level rise.
President Obama saw this and spoke out about it but candidate Donald Trump ridiculed him for his comments.