It's caused due to sweating to the oldies! But seriously, its caused by bovine flatulence, solar activity, volcanic activity, natural gas venting, internal energy increase, entropy, chaos theory, numerous other sources. Think about it...we have faced cycles of ice ages and warm periods. What makes this current trend an area odf grave concern to all civilization?
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These factors do contribute to climate change. Look it up yourself. Cow flatulence is major factotr in methane production, which even GWists admit to climate contribution.
Emissions from livestock raised for human consumption is considered an anthropogenic source. There wouldn't be all those cows belching and farting if we didn't want to eat them.
Change in solar activity
can and
has influenced climate change in the past, but it's not doing so now. According to research done by the
PMOD at the World Radiation Center there has been no increase in solar irradiance since at least 1978 (which is when accurate satellite measurements of solar activity began). And research done by the
Max Planck Institute indicates that there may have been no increase since around 1940. So it's highly unlikely that the sun is the cause of the warming trend.
Volcanic activity has been pretty much average for quite some time now. And since volcanoes emit mostly aerosols in the form of dust, sulfates, and ash, the net effect of a volcanic eruption is a cooling one. (
Source: RealClimate.orgEntropy, internal energy increase(?), and Chaos theory have nothing to do with anything, and were seemingly pulled from your ass.
What makes this current trend so consternating is the fact that these other past changes you speak of had an annoying tendency to cause mass extinctions; especially changes as rapid as the one we're currently undergoing. Also of note is the fact that our entire civilization is tailored to the way the climate is
now; changes in sea level, more frequent and severe droughts, floods, storms, etc. Plus a complete disruption of many ecosystems upon which we depend isn't exactly going to be a picnic.