You don't think scientists have looked at this? Ice core data is giving us clues to past climate variations.
Talking with guys in the field (not politically motivated), I find that there is really hard evidence that indeed we are warming.
The rub is, have humans contributed to the situation or is it just one of the natural cycles that will continue as long as the Earth exists?
The other rub is will any efforts on our part to "curb" this trend result in a worse situation in the long run?
Talking with guys in the field (not politically motivated), I find that there is really hard evidence that indeed we are warming.
Again on what time scale!! Random variation about an overall trend does not make for change in earth's climate.
Ice Ages & Astronomical Causes Origin of the 100 kyr Glacial Cycle Figure 1-1 Global warming Figure 1-2 Climate of the last 2400 years
Figure 1-3 Climate of the last 12,000 years Figure 1-4 Climate of the last 100,000 years Figure 1-5 Climate for the last 420 kyr, from Vostok ice |
Another that may be of interest to you specifically:
Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity Origin of the 100 kyr Glacial Cycle
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Along with some rather interesting observations by others:
http://www.newscientistspace.com/article/dn9228-mysterious-glowing-clouds-targeted-by-nasa.html
Mysterious glowing clouds targeted by NASA
26 May, 2006High-altitude noctilucent clouds have been mysteriously spreading around the world in recent years (Image: NASA/JSC/ES and IA)
http://newton.ex.ac.uk/aip/physnews.252.html#1
INTERPLANETARY DUST PARTICLES (IDPs) are deposited on the Earth at the rate of about 10,000 tons per year. Does this have any effect on climate? Scientists at Caltech have found that ancient samples of helium-3 (coming mostly from IDPs) in oceanic sediments exhibit a 100,000-year periodicity. The researchers assert that their data, taken along the Mid-Atlantic Ridge, support a recently enunciated idea that Earth's orbital inclination varies with a 100-kyr period; this notion in turn had been broached as an explanation for a similar periodicity in the succession of ice ages. (K.A. Farley and D.B. Patterson, Nature, 7 December 1995.)
Farley & Patterson 1998, http://www.elsevier.com/gej-ng/10/20/36/33/37/32/abstract.html
Farley http://www.gps.caltech.edu/~farley/
Farley http://www.elsevier.nl/gej-ng/10/18/23/54/21/49/abstract.html
http://www.publicaffairs.noaa.gov/pr96/dec96/noaa96-78.html
ABRUPT CLIMATE CHANGE DURING LAST GLACIAL PERIOD COULD BE TIED TO DUST-INDUCED REGIONAL WARMING
Preliminary new evidence suggests that periodic increases in atmospheric dust concentrations during the glacial periods of the last 100,000 years may have resulted in significant regional warming, and that this warming may have triggered the abrupt climatic changes observed in paleoclimate records, according to a scientist at the Commerce Department's National Oceanic and Atmospheric Administration. Current scientific thinking is that the dust concentrations contributed to global cooling.
Yes, warming -- and drying in some parts of the world that have been used to more rainfall. In the lifetimes of many of us, months of heavy snowfall and blizzards were common in winter across much of the lower 48 states. Now it's relatively uncommon.
Hot weather of 100 degrees or more as far north as Seattle were very rare. Now they are not uncommon.
As you say, is this warming due to human activity or a natural cycle, or a combination of both. I think it's the latter.