My debate on global warming

I participated in a debate: Observed global warming has not been proved mainly anthropogenic.

I am posting this so that any with ideas for improvements can share. Debating this topic is probably a total waste of time—that is my current thinking, and was before I decided in a moment of lunacy that a debate might generate useful discussion among those who accept mainstream science but are not motivated to act. But just in case there are better ways to handle it, please share. In this case, those who supported the assertion (not been proved) are libertarian leaning. An evangelical audience has different concerns. (Several people claimed to change their mind based on the debate, but they appeared to be changing to what they had believed all along.)

Format: we each get 6 minutes to introduce our ideas, 3 minutes to rebut, an hour for people to share their thinking, and 3 minutes at the end for a summary statement.

My Introduction

Science starts with observations. From there, scientists produce as many explanations as they can for what they see. These explanations provide models that make predictions. If the predictions fail, scientists rework or discard the models. In the case of global warming, for 2 centuries physicists have been discussing the models, based on data that goes back much further.

If you wish to dispute current thinking, you, like scientists, will need to both explain the errors for the last 2 centuries of physics, and propose alternative explanations. So what is the current thinking? The following 3 facts are incontrovertible.

Fact 1: We know Earth is warming.

Fact 2: We know which gases hold in heat, and that these greenhouse gases are increasing in proportion to our use of fossil fuels.

Fact 3: We have multiple lines of evidence showing the increase in gases and the warming are related.

So let’s take a look at those 3 facts.

Fact 1: How do we know Earth is warming? We know it from direct measurements of land and water, from shifts in where animals and plants live, from rapid increases in glacier and ice sheet melt, from sea level rise (due less to melting ice, and more to expansion as the water warms). And since the 70s, satellite data shows more heat into our atmosphere than out.

It’s true that the temperature varies year to year with volcanoes (colder), La Ninas (colder), and El Ninos (warmer), but the trend is up, and currently Earth is 1.6°F warmer, most of that gain in the last 1/2 century. Indeed 2014, an El Nino neutral year, was warmer than 1998, the strongest El Nino on record, as temperatures currently rise 0.3°F/decade. The oceans show this warming even more dramatically; 90% of the extra heat is stored there. Sea level was essentially stable for centuries, then rose 5” in the first 90 years of last century, and is now rising at the rate of 15”/century.

Fact 2: We know which gases hold in heat, and that these greenhouse gases are increasing in proportion to our use of fossil fuels.

By the middle of the 19th century, we knew that carbon dioxide and methane keep Earth warmer. These gases are in our atmosphere naturally, but they are also released by our use of fossil fuels. In the mid-20th century, it was shown that the ocean wasn’t absorbing all of the CO2, as most scientists had expected. Scientists also found the ratio of carbon isotopes in the atmosphere to be changing over time due to our use of fossil fuels. Today, carbon dioxide, the most important GHG, is 400 ppm in our atmosphere, up 40% from pre-industrial times.

Fact 3: We have multiple lines of evidence showing the increase in gases and the warming are related.

Hard evidence was found in history seen in ice cores. The Air Force studied the atmosphere in the Cold War to make heat-seeking missiles. Understanding has been checked against other planets and moons with atmospheres. That spectroscope shows which kind of light is present, but also, what is missing—when satellites in the 70s began looking at energy leaving Earth’s atmosphere, they found huge chunks of energy missing which show signatures for carbon dioxide and the other greenhouse gases, and these missing chunks become larger as we add more greenhouse gases. Then in the 80s, the ice cores showed rapid change in the past, not as rapid as we are inducing this century, but change didn’t have to take millennia as was once thought.

The models successfully predicted what we are seeing today. 19th century predictions include:
• carbon dioxide and other greenhouse gases warm Earth, and how fast.
• warming would be larger at night and in the winter.
• Polar regions would warm faster, and the Arctic faster than the Antarctic.

Predictions continued successfully into the 20th and 21st centuries.

There wasn’t much interest at first in these predictions. First, there was conventional wisdom, the ocean had been buffering change for centuries, and scientists couldn’t believe that it wouldn’t continue. It took one century to overcome this belief, when measurements were first made in the mid-20th century. Also, having overcome religious ideas of sudden change, scientists expected change to always be slow. Another was that the amount of carbon dioxide needed to see an effect seemed inconceivably large in the 19th century.

Social scientists say that when we don’t like solutions, we deny the problems. But the problems are real. Climate change is already seen as serious, and the current model predicts it will get a lot worse.

• As predicted, or faster than predicted, we are seeing shifts in rain and declines in food production. This will continue. On our current path, NASA says that by mid-century much of North America will move into megadroughts, worse and longer lasting than the Dust Bowl era.

• Sea level rise of 15’ or more due to Antarctica melt alone look inevitable, although it may take a couple of centuries or more or much more. Or it may not take that long.

• By the time today’s teens are in their 80s, or maybe even in their 60s, we may see as much change as between an ice age and the interglacial periods. Instead of people not being able to find places to live because of ice 1 mile thick over Wisconsin, they won’t be able to find places to live because of sea level rise, and much of the world becoming too hot or dry for humans or for our agriculture.

We’ll soon know whether these predictions, like so many others, will come true. I prefer that we act early enough so that we never learn.

Concern about climate change has come from many quarters: the insurance industry, Olympians in winter sports, the beer and coffee industries, worried about hops and coffee, Nike and Coke, worried about water and other ingredients, the national security types, worried about climate change enhancing other problems, and making one heck of a lot of Bangladeshis move.

It seems to me more than perverse not to pay attention to the knowledge we have spent so much time, money, and effort obtaining.

My Summary

The last two centuries of physics has tested the premises of the greenhouse effect and the prediction that our use of fossil fuels would heat Earth. It required improvements in spectroscopes and other equipment, improvements in the theory, finding confirmation in the past and on other worlds. It also required us to confirm that the oceans wouldn’t protect us, that change can happen relatively suddenly.

Other explanations offered tonight do not explain the observations, including the energy missing when it leaves Earth, right where the greenhouse gases are absorbing it. Yes, you will always find OJs who continue to seek whose glove was found, more tests are needed!, but these people have not offered alternative explanations and found errors in mainstream thinking.

Civilization developed during a time of enormous stability in the climate. Food could be grown in the same area for centuries with good cultivation methods. Large cities could mostly exist for centuries or millennia without needing to move buildings, roads, ports, and other infrastructure. Currently, we depend on that stability when we make decisions. That stability is being taken away…

We are confronting major costs to our way of life, and if we are foolish, we threaten it completely. And in response, some say, well do more tests, we don’t know enough yet. (Cover eyes and ears.)

This is about us, facing our responsibility, without getting so freaked out that we don’t want to act. It is a challenge to face such scary predictions and feel so helpless to make a difference. But accepting facts is where we begin the journey to meaningful action.

Challenges Made by the Hasn’t-Been-Proven Crowd

Those who assert that global warming has not been proved, both the main speaker and those who commented later, made a number of claims. There were too many to rebut all of them in the time allotted. I will provide links to responses, whether the response was provided in the debate or not.

• Earth has warmed only 0.6°C, and warming stopped in the 40s, although GHG emissions rose after that.
—Here is NOAA’s report from February 2015.

• IPCC has a history of being politicized, and skeptical scientists claim to be censored.
—Insufficient details provided, so no response provided.

• Most scientists are paid by the government and are therefore untrustworthy. I assume that the speaker is including state universities, where most climatologists work. This speaker put forth as an alternative the work of Willie Soon, who has been paid more than $1 million by fossil fuel interests.
—This meme arose during the Bush Administration, and so is doubly strange. It is true that most scientists around the world who work on climate issues do work for their government, in a variety of states, in a variety of countries. However much of the original work was done by rich people who didn’t need to be paid.

• The term denier is offensive.
—No one else used this term besides the speaker.

• There has been natural climate change in the past.
—Natural climate change doesn’t disprove anthropogenic change today any more than natural death disproves murder.

• Another person mentioned the Little Ice Age and the Medieval Warm period.
—The same answer holds, that previous natural climate change doesn’t disprove anthropogenic change today.

Scientists ascribe the causes of the Little Ice Age to increased volcanic activity and a cooler sun.

During the Medieval Warm Period, the North Atlantic was warmer than usual, but the planet as a whole was not.

• The media treat the science as settled, and generate false urgency.
—Doesn’t show that the media are wrong.

• Some hard to follow graphs were provided to show that the sun is actually the main driver of global warming, a much better fit to the data.
This appears to be one of the graphs. The idea that it is solar is addressed here.

• Or it could be cosmic rays.

• Scientists are wrong because they created a big scare over global cooling in the 1970s.
—Some of the media did, but most? all? scientists who brought up cooling were warning about an ice age in thousands of years.

• 2014 not the warmest year, the record has been flat.
—Here is NOAA’s report from February 2015.

• The increase in CO2 could be volcanoes.
—For this argument to be meaningful, the speaker must accept the importance of increasing atmospheric CO2.

It doesn’t really show up much in the Keeling curve, even though Mauna Loa is a volcano.

USGS addresses the importance of volcanoes to added atmospheric CO2.

• Models are wrong.
—Scientists say all models are wrong, some are useful. The biggest problem seems to be for ice sheet melt, in the discrepancy between the paleoevidence and the models, with models producing rates of melting far below both the paleoevidence and current observations.

• People have forgotten the alarmist projections of computer models.
—Insufficient details provided, so no response provided.

• Scientists are lazy, unwilling to buck the system.
—Buck the system successfully and one gets a Nobel. Interestingly, none of those who opposed the anthropogenic argument were willing to confront an ally on purported facts, such as the lack of warming since 1940.

• Temperature increase in the paleo-record comes first.
—That is true. There was temperature increase due to orbital changes, which led to CO2 increase which led to greater warming.

• Scientists are wrong, all of them, in asserting that their evidence is valid. It is only possible to ascertain if CO2 heats Earth with a large set of Earths a la medical research, and statistics.
—One type of response some wonks give to this kind of argument is, “Wow, no one in physics ever considered that idea.” This is not intended as a compliment.

• The solutions are bad and costly.
—If we don’t like the solutions, we often deny the problems.


I still want your ideas—What might have worked better with this particular audience? Or just give it up?

2 Responses to “My debate on global warming”

  1. For me, the biggest problem with the debate was the wording of the agreed upon question:
    This House supports that observed global warming has not been proved mainly anthropogenic.
    You probably would have gotten more agreement if people were not hung up on what constitutes proof. Few people understood the difference between a scientific debate and a political or courtroom debate. You expressed frustration when people say, “We need more testing. We need more evidence.” We had a good laugh when you responded, “Yeah, and OJ Simpson is still looking for the owner of that glove!”
    In a political or courtroom debate, you attack the credibility of the witness if you can’t attack the credibility of the evidence. Therefore, scientists in universities are suspect because they take money from government agencies that would gain from findings that support more government regulations. As someone at the debate pointed out, scientists are motivated to disrupt the established order. They actually help their careers by proving long held beliefs to be wrong.
    You can also bring sympathy to your side if you claim to be the victim; there is a conspiracy to silence scientists who doubt humans are causing climate change, and the media is a part of this conspiracy to keep the public ignorant. A peer reviewed scientific journal is different from the op ed page of a daily newspaper. To get published in a scientific journal, the paper has to go through that peer review process. You can’t say, “Hey, publish me because I have a different opinion!”
    I did have a fun time at the debate, and I can understand why you felt you had wasted your time. As expected, very few opinions changed that night, including mine. You did a good job, and I am sure the exercise helped you improve your message that may sway more people who are on the fence. By accepting the offer to debate, you showed that you are confident in your own research and can respond to any talking point the doubters throw at you.

  2. Shelley T says:

    I greatly appreciate that you were willing and able to do this. It is always hard to know what impact you have as a result of a presentation. Not many people are going to change their minds in that moment, but hopefully, they will think about what you said and become more open to change as a result. Thank you for participating in the debate!