Climate heating – Population Matters-USA

Image courtesy of NASA

It’s been unmistakably hot outside, but some people have different ways of dealing with what most of us recognize as anthropogenic climate change.

I asked one acquaintance what he thought about climate change. We had met when I was selling beer with our Bayfield Rotary Club on the 4^th of July. He had come back several times for more beer. When I commented on this, he responded with “Those cans must have holes in them—the beer just seemed to leak away!”

At a chance encounter, I asked him if he thought that climate change was real. “Oh yes, it’s real. Remember that explosion in the power plant in Japan? Well, it knocked the planet 3 degrees off its axis. That’s why the climate is all screwed up!” I think that is as rational as his reason for getting so many cans of beer.

Gail and I were eating dinner with friends recently. I cannot remember how the subject came up, but I asked the person sitting next to me what they thought was making the climate so hot.

“I think it’s a cycle.”

I know this person to be intelligent and responsible. However, I was too flabbergasted to respond, so I changed the subject. The last time Earth’s climate was so hot as it is now was 125,000 years ago. That’s one loonngg cycle!

The way ancient temperatures are estimated is amazing. Scientists measure stable isotopes of oxygen and of hydrogen in air bubbles in Antarctic ice cores. There are known relationships between isotopes and atmospheric temperatures.

We are very good at finding excuses for, or denying completely, what is incompatible with preconceived notions. This is especially true with facts that might interfere with our income or religious beliefs. Misinformation is rampant on Internet, in churches and from politicians.

Let’s look at the facts of climate change. First, is it real?

Yes, climate change is real. There are indications that humans have changed the planet’s climate for millennia, but previous to now, in insignificant ways. The human effect on climate increased after the Industrial Revolution. Then temperatures started to skyrocket about 1950.

What is causing our climate to get hotter? We’ve all sat in a parked car in the summer and know how hot it gets from the greenhouse effect. The energy of the sun gets trapped in the closed environment. We also know that atmospheric carbon dioxide (CO₂) is increasing from human use of fossil fuels. However, it may be difficult for people to accept that CO₂is as effective as a car in holding in heat. Other gases, such as methane in natural gas, are even more effective than CO₂ as greenhouse gases.

Is climate change just in the future? NO! Severe storms, melting glaciers, enormous fires, the high temperature and drought we’ve experienced are all caused by, or worsened by, what we have done to the climate. Despite good snows last winter, the mega-drought of southwestern North America has been partly caused by the greenhouse gases we have wrapped around our planet.

How can we slow climate chaos? Driving electric is good, but less travel is even better. Increasing efficiency with LEDs helps, so does eating less meat. However, still the best way to reduce your individual carbon footprint is by having a small family—and by encouraging others to do the same. Global population has more than tripled since I was born 80 years ago. The more people, the more CO₂ is emitted.

We need to admit that we humans are responsible for climate change before we can conquer it.

©Richard Grossman MD, 2023

Trees killed by drought and spruce beetles on Wolf Creek Pass

It is windy, hot and dry, dry, dry here. According to www.drought.gov, Durango is in an extreme drought. What’s going on? Do we need to start doing rain dances?

Past droughts have brought us some pretty destructive fires. Remember the Missionary Ridge and Valley fires in 2002? More recently the 416 fire in 2018 did dreadful things to the local economy and burnt 52,000 acres of forest. Fortunately there were no serious injuries or burnt structures. Thank you, firefighters! Very dry conditions predispose us to wildfires, of course. Even if your property isn’t burnt, we all suffer from the costs of firefighting and many of us from smoke-worsened respiratory problems.

Much of our water supply falls in the winter as snow. Snowfall this past winter started off looking good. However, in March precipitation dwindled so it seemed as though somebody turned off the tap. The cooler-than-average spring helped hold some of the moisture in the mountains, but now the snow has melted. We need the monsoons to bring us rain!

A large area in the southwest of the USA has been affected by drought–but that isn’t anything new for this region. Tree ring records tell us the Ancestral Puebloans (also called “Anasazi”) survived dry periods in the 9^thand 12^th centuries. Finally, after about 1150 it got so dry here they started migrating to the Rio Grande valley, archeologists tell us.

Reality appears more complex, however. The human population grew during the wetter years between droughts. When the megadrought hit in the 1150s, violence erupted, just as it did in Rwanda when people were starving. There were even signs of possible cannibalism in the 12^th century at Cowboy Wash, near Mesa Verde.

What are “megadroughts”? People who study droughts rely on dendrochronology (the study of tree rings) to look at the prehistoric past. A drought lasting 20 years or longer qualifies as a megadrought. Another definition is that it is any drought worse than anything the USA experienced in the 20^th century–including the Dust Bowl. From a sociological standpoint, megadroughts usually cause mass migrations of people. What is unusual is that is that people are migrating toan area of drought. We are so disconnected from the natural world that we can live in comfort with air conditioning and imported food.

The natural variability of weather and climate is thought to be the main cause of megadroughts, but there are at least two other contributing factors that are human caused. An example of a local effect is in Rajasthan, India, where the Thar Desert was once forested. Alexander the Great’s army, amongst others, cut down trees to build ships to cross the Indus River in the 320s, BCE. It is thought that this destruction of forests may have been a factor in this desertification.

Global climate heating has had a much wider effect on our climate than in just one location. It is generally accepted that the climate crisis is anthropogenic, so the more people there are and the more each of us consumes, the worse the heating.

Rajasthan is an example of how cutting down trees can change the local climate. Can planting trees help? The amazing Kenyan woman, Wangari Maathai, started a movement that may help answer the question. The Green Belt Movement she started did much more than just plant 51 million trees; Dr. Maathai used trees as an entry point for community development. Increasing women’s income, justice and reduction of poverty are among the humanitarian goals. The environmental goals are to combat deforestation, provide firewood for cooking and protect the watershed. This quote from a UN report shows success:

“Because of the deforestation, natural springs that fed the Chania River dried up, making the river’s water levels very low. The reforestation efforts of the women in the watershed have led to the rejuvenation of 65 springs. And the microclimate is enhanced in the planted areas: ‘We have noticed more rain since we planted the trees. When I came in 2008, you could walk across the river; now, it is almost back to historic levels’, said Joyce Nyambura, a Green Belt Movement Extension Officer.”

Back to the American Southwest. We are in the midst of a megadrought which started in 2000. It made worse by the increasing number of people and their demand for water almost doubling. A study has looked at the causes of this dryness and found that climate heating is a major factor for our drought. The authors calculated that only half is due to natural variation; the other half of the cause of the scarcity of water is anthropogenic.

It is too late to prevent our current megadrought, but hopefully the natural cycles of nature will bring rain to this parched land. What we can do to protect the next generations—indeed, must do–is to decrease our consumption and slow population growth.