*The planet has warmed since the mid-1800s, but before that it cooled for more than five centuries. Cycles of warming and cooling have been part of Earth's natural climate history for millions of years. So what is the global warming debate about? It's about the proposition that human use of fossil fuels has contributed significantly to the past century's warming, and that expected future warming may have catastrophic global consequences. But hard evidence for this human contribution simply does not exist; the evidence we have is suggestive at best. Does that mean the human effects are not occurring? Not necessarily. But media coverage of global warming has been so alarmist that it fails to convey how flimsy the evidence really is. Most people don't realize that many strong statements about a human contribution to global warming are based more on politics than on science. Indeed, the climate change issue has become so highly politicized that its scientific and political aspects are now almost indistinguishable. <ref>[http://goliath.ecnext.com/coms2/summary_0199-2875898_ITM Global Warming: Both Sides] </ref>
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*The planet has warmed since the mid-1800s, but before that it cooled for more than five centuries. Cycles of warming and cooling have been part of Earth's natural [[climate history]] for millions of years. So what is the global warming debate about? It's about the proposition that human use of [[fossil fuels]] has contributed significantly to the past century's warming, and that expected future warming may have catastrophic global consequences. But hard evidence for this human contribution simply does not exist; the evidence we have is suggestive at best. Does that mean the human effects are not occurring? Not necessarily. But [[media coverage]] of global warming has been so alarmist that it fails to convey how flimsy the evidence really is. Most people don't realize that many strong statements about a human contribution to global warming are based more on [[politics]] than on [[science]]. Indeed, the climate change issue has become so highly [[Politicization of science|politicized]] that its scientific and political aspects are now almost indistinguishable. <ref>[http://goliath.ecnext.com/coms2/summary_0199-2875898_ITM Global Warming: Both Sides] </ref>