Infrared Radiation, Black-bodies, and Temperature

This post is part of a primer on infrared spectroscopy and global warming. The previous post discusses the nature of  infrared radiation. This post starts the process of looking at the interaction between infrared radiation and matter and discusses black-bodies and the relationship between temperature and infrared radiation.

 

Figure source.

What is Infrared Radiation (IR)?

This post is part of a primer on infrared spectroscopy and global warming. The  main post gives an overview of the topic and provides links to each of  the sections. This post examines what infrared radiation (IR) is, a necessary first step to understanding the importance of IR in discussions about global warming.

Figure source

IR is a type of electromagnetic radiation; so the starting place is to understand electromagnetic radiation.

"Glacier-Gate" and Healthy Skepticism

The last report of the The Intergovernmental Panel on Climate Change (IPCC) contained the claim that there was a probability that the glaciers in the Himalayas would melt by 2035.  It now appears that such a claim never should have been made.  It is instructive to review the bidding to see how this claim appeared in the report.

The claim stated:

Glaciers in the Himalaya are receding faster than in any other part of the world (see Table 10.9) and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate. Its total area will likely shrink from the present 500,000 to 100,000 km² by the year 2035 (WWF, 2005).

First, I provide some background on the IPCC. Second, I discuss the source of this claim, and  third,  I  discuss what this error means. My conclusion is a discussion of healthy skepticism and what it means. Those who claim that the IPCC made an error and therefore climate science is a hoax, are not healthy skeptics of the sort I mean.

Voltaire's Poem on the Lisbon Disaster (1756)

The link below has the poem and also some discussion of its context. the poem is a reply to those like Pope and Leibniz who proclaimed that all is well. 

"UNHAPPY mortals! Dark and mourning earth!
Affrighted gathering of human kind!
Eternal lingering of useless pain!
Come, ye philosophers, who cry, "All’s well,"
And contemplate this ruin of a world."

http://courses.essex.ac.uk/cs/cs101/volt/Lisbon2.htm

The Beer-Lambert Law

Introduction 


This post is part of a primer on infrared spectroscopy and global warming. The previous post  looks at the features of the spectra of molecules of interest molecules and radiation and discusses how molecules give rise to infrared spectra.  This post looks at the question of how much radiation is absorbed by gas phase molecules in a laboratory setting and examines some of the differences between the laboratory gas cell and the earth's atmosphere.

Please Consider Donating to Help the Haitian People

By now everyone is aware of the devastating earthquake it Haiti and its aftermath.  10s or perhaps 100s of thousand of people have died.  More will die without aid.  The Haitian people need your help, not just now, but in the weeks and months to come.  There are many options to help.

You can donate to the American Red Cross International fund online.  You can even make your payment through Amazon.

Earthquake Devastates Haiti

http://www.latimes.com/news/nation-and-world/la-fg-haiti-quake13-2010jan13,0,7871308.story