As you contemplate this week's talks by Elizabeth Kolbert and Patrick Michaels, take a look at books received yesterday and now on the new book shelf:
Global warming in the 21st century / Bruce E. Johansen. This three-volume set includes 100 pages of bibliographic references and devotes an entire volume to melting ice and warming seas, phenomena that are readily observed and measurable in the upper latitudes of both hemispheres.
Kolbert's book is also in the library, as is Al Gore's (both currently checked out, but more copies of Kolbert's book are on the way). Note that an author search in OBIS on Gore, Al 1948-
results in 62 items, including the 1993 Climate Change Action Plan by President Clinton and Vice President Gore.
Clicking on one of the subject headings (Global Warming - Government Policy - United States) for that report leads to a host of other items, including hearings before congress and status reports on the Kyoto Protocol.
Also useful is a search of Patrick J. Michaels as a cited author in Science Citation Index. See what other scientists write in reference to his publications. As with any controversial topic, explore a variety of sources to get the information you need to assess the validity of competing claims and hypotheses.