News Flash!! Climate is Changing!

Climate is changing, but then it always has. That is not controversial. It certainly isn’t news.

Nonetheless, we are daily treated to articles like a recent Op-Ed by Thomas Friedman in the New York Times which adds nothing to our understanding of the climate situation. His wonderful descriptions of Greenland and individual impressions of how the weather has changed tell us nothing about the cause of those changes. Friedman's use of these images to paint a tragic picture of changing climate is simply an emotional appeal which takes as a given that human CO2 emissions are the cause.

But is it? What is the evidence? Friedman offers none. Does the science actually support the conclusion that human CO2 emissions are causing harmful climate change? Or have we just been inundated by decades of repetition so that now we accept it as true in spite of the fact its scientific status is still controversial?

Stop. Think. On what scientific facts and climate theory are you basing your opinions? Are you familiar with the major scientific challenges to the current “consensus” on anthropogenic (human-caused) climate change? Is there validity to the data and arguments presented by those who disagree (also here and here) with both the conclusions of the Intergovernmental Panel on Climate Change as well with the very process that generates that body’s science and its Summary for Policy Makers? What are the criticisms being offered to the standard view of catastrophic global warming? Is there any merit to those criticisms? What do you actually know, as opposed to what have you heard?

One simple question to consider: Is the average global temperature increasing?

It depends. What time frame are you considering?

The earth’s temperature has been changing ever since it formed. From a 600 million year perspective, we are currently in a relatively cool phase. (*)

Figure 1 Average Global Temperature 600 million years to present

If you look at the temperature record for the past 400,000 years, we are currently at an interglacial temperature peak.

Figure 2 Temperature difference over the past 400,000 years


A close up examination of temperature estimates for the last 3000 years shows us emerging from the Little Ice Age.

Figure 3 Surface Temperature of the past 3000 years

Zooming in to the last 150 years shows two periods of warming: 1900-1940 and 1960-2000.

Figure 4 Average temperature difference for the past 140 years

The first warming period occurred before any significant change in atmospheric CO2 and had to occur for some other reason. So why so much confidence that the second warming period is caused by human CO2 emissions?

Proponents of CO2-induced global temperature change frequently refer to a pair of charts which demonstrate a remarkable correlation between historical CO2 levels and global temperature. Figure 5 Temperature and CO2 for the past 400,000 years

These charts tell us nothing about which is cause and which is effect. It could be either. However, let’s zoom out from this view of the last 400,000 years and look at our best estimates of CO2 and temperature over the past 600 million years.
Figure 6 Temperature and CO2 over the past 600 million years

The correlation no longer is so clear.

Fact: there is no general theory of climate which adequately explains changes past or present. There is much that is understood, but crucial areas are poorly understood. Complexity in and of itself is not a reason for skepticism, but climate science is both complex and young. There are large gaps in our knowledge, not just of data but of the fundamental principles which are operating: the roles of ocean currents, cloud cover, precipitation, water-vapor feedback, cosmic rays. Even by estimates of the IPCC, much of our scientific level of understanding is “low.”

Why this topic in a blog on wealth? Because the promoters of catastrophic anthropogenic global warming are telling us that we need to drastically reduce our consumption of energy in order to save the planet. The economic effects of mandating the switch away from fossil fuels to more expensive energy alternatives will be devastating to the millions of people living “at the margin.” Be sure you adequately understand the science before you vote to condemn them to poverty, or worse.

And be on the look out for articles like Friedman’s which are mere emotional appeals promoting a political solution without addressing the controversial aspects of the underlying science.

(*) Figures 1-6 taken from “A Global Warming Primer” by the National Center for Policy Analysis. The primary sources for the data are cited at the end of the Primer.