GLOBAL WARMING

Science vs Politics: Climate Change

I am just a poor boy.
Though my story's seldom told,

I have squandered my resistance

For a pocketful of mumbles,

Such are promises

All lies and jest

Still, a man hears what he wants to hear

And disregards the rest.

                                                                      The Boxer, Paul Simon

 

I have to admit that I bring to this particular topic a sense of futility and anger with the people to whom we've given the power to control our future. An example of this is James Inhofe, an elected member of the United States Senate, expected to take over the Senate Environment and Public Works Committee. He’s a Republican from Oklahoma, who has been calling global warming a “hoax” for years—that’s nothing new. He claims that the idea that man-made pollution could affect the climate is “arrogance,” because, as he believes we all know, only God can affect the climate.

As he puts it in his own words:

Well actually the Genesis 8:22 that I use in [my argument] is that “as long as the earth remains there will be springtime and harvest, cold and heat, winter and summer, day and night.” My point is, God’s still up there. The arrogance of people to think that we, human beings, would be able to change what He is doing in the climate is to me outrageous.

That’s scary.  I’m not against the democratic process. But our elected officials don’t always come up to the demands of the position.

Pete Seeger wrote a song about this. You can listen to it at this link  but here are the relevant words:

What did you learn in school today,


Dear little boy of mine?


I learned our government must be strong.


It's always right and never wrong. 


Our leaders are the finest men.


And we elect them again and again...

OK. I got that off my liberal chest! Let’s move on.

Climate Change is occurring.

There is a lot of denial of this fact. Some of this denial is out of ignorance, and some is deliberate. I want to provide the reader an opportunity to examine the facts and how they were obtained. I want to examine false and misleading beliefs, and how to make a judgment between fact and belief.

The question of whether the Earth is warming on a global scale has become quite heated, and serves as an avenue for discussing the conflicts between belief and fact, and specifically in this case the interactions of politics and science. In several posts that follow I want to outline the science relevant to long-term changes in climate, discuss the evidence that global warming is occurring and that human-controlled factors play a major role, and consider the attacks mounted by those who believe that global warming is a scheme of the “radical environmental movement” (quoting Sarah Palin) as revealed by the “climate e-mail scandal” (Palin again) which exposes “fraudulent scientific practices” (more Palin).

Let’s not deal with revelation at this stage. Let’s look at some everyday facts. The temperature of the Earth’s surface varies dramatically from one locale to another, and often from day to day in any one place. In San Diego, California, the seasonal extremes of daily temperature are roughly from 40°F to 100°F. In my previous home in Amherst Massachusetts the range is greater, perhaps from -10°F to 95°F. Scientists investigating Global Warming are concerned about possible temperature rises of just 2 to 4°F. What’s the big deal?

First, we have to differentiate between “weather” and “climate.” Weather deals with the instantaneous state of the atmosphere at some specific place on the earth. If I say there was, or will be a thunderstorm in London on Thursday afternoon, that's a statement about the weather, either observed or predicted. But climate deals with longer time scales and with average temperatures and other statistics over both space and time. If I say London next summer will be drier and warmer than usual, that's a statement (in this case, a prediction) about climate.

A key concept here is that climate deals with long time scales. Weather is a short-time-scale event. The significance of this difference is that life in a particular place can deal with short-time-scale variations. If the temperature rises or falls 20°F during a day, humans can seek shelter, put on more appropriate clothing, or even suffer through the heat or cold for a few hours. And while a sudden overnight frost could damage a farmer’s fruit crop and lead to significant financial effects, more generally the flora on earth survive unexpected changes in weather. And because weather changes occur over short time scales, people can moderate the effects of sudden changes in weather, with shelter and appropriate clothing. Animals and plants have developed natural means of protecting themselves from sudden temperature changes, such as a thick layer of fat or the bark of a tree.

On seasonal time scales, many animals respond to the onset of winter by hibernating or migrating. Annual plants may die off from the onset of a prolonged cold period, but they may produce seeds that are protected against the cold and that yield the next generation of the species when the “growing season” arrives. Trees survive harsh winters to leaf out again in the spring. Through millennia of evolutionary adjustments, “nature” has developed mechanisms to insure survival against short-term (seasonal) variations in weather.

The concern is not with the weather. The concern is with the longer-term changes in the climate of the earth. We begin with a few basic questions.

1: Is the earth’s climate changing?

2: If so, is that due to human actions?

3: What is the scientific consensus on climate change?

An analysis of the abstracts (short summaries) of nearly a thousand scientific publications in the peer-reviewed literature (over the ten-year period 1993 to 2003) shows that the vast majority of scientists agree with the IPCC (Intergovernmental Panel on Climate Change), the National Academy of Sciences, and the public statements of their own professional societies: global warming is happening, and humans are contributing to it. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect. 

This acceptance of scientific evidence, (we will need to define “scientific evidence,” and examine evidence later) widely held within the science community, continues to the present. On October 21, 2009 a letter to members of the U.S. Senate was sent by the American Association for the Advancement of Science. 

The American Association for the Advancement of Science (or AAAS) is an international non-profit organization with the stated goals of promoting cooperation between scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the betterment of all humanity. The AAAS is the world's largest general scientific society, with over 100,000 individual and institutional members, and it is the publisher of the well-known scientific journal Science. 

The letter, endorsed by the leaders of 18 scientific associations, follows.

Dear Senator:

As you consider climate change legislation, we, as leaders of scientific organizations, write to state the consensus scientific view. Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver. These conclusions are based on multiple independent lines of evidence, and contrary assertions are inconsistent with an objective assessment of the vast body of peer-reviewed science. Moreover, there is strong evidence that ongoing climate change will have broad impacts on society, including the global economy and on the environment. For the United States, climate change impacts include sea level rise for coastal states, greater threats of extreme weather events, and increased risk of regional water scarcity, urban heat waves, western wildfires, and the disturbance of biological systems throughout the country. The severity of climate change impacts is expected to increase substantially in the coming decades. If we are to avoid the most severe impacts of climate change, emissions of greenhouse gases must be dramatically reduced. In addition, adaptation will be necessary to address those impacts that are already unavoidable. Adaptation efforts include improved infrastructure design, more sustainable management of water and other natural resources, modified agricultural practices, and improved emergency responses to storms, floods, fires and heat waves.

We in the scientific community offer our assistance to inform your deliberations as you seek to address the impacts of climate change.

While there is room for continued debate on the details, it is fair to state that the vast majority of scientists trained in the research methodologies of geophysics, climatology, meteorology, statistical analysis, etc., now believe, on the basis of measurable scientific evidence, that global warming is occurring and that it is largely anthropogenic [man-made]. Unfortunately, the Senate of the United States does not accept this science-based and hugely documented opinion. Actually, nearly all Democrats believe this, and nearly all Republicans either deny the facts, or are unwilling to go on record against their party's stand. Climate Change is not a political, ideological issue. See the following report of this recent (January 2015) Senate vote .

We should turn then to the next questions:

What is the evidence that warming has already occurred? What is the extent of anticipated (predicted for the future) changes? What is it that gets “warm,” and by how much? How soon?

Before going there however, let’s look at the physics of climate change, and in particular the chemical and physical factors that control the temperature of the earth. We begin with the Greenhouse Effect.