Because scientists thought it was supposed to be warming.
http://wattsupwiththat.com/2010/08/13/is-jim-hansens-global-temperature-skillful/
That hasn’t been going according to plan, so the global warming cult has had to change the name to “global climate disruption.”
Given that the climate is a huge, chaotic, poorly understood, constantly changing concept – there is absolutely no way to prove that it is either disrupted or not disrupted.
Every weather event can now be blamed on “global climate disruption.”
“We can’t say for sure that this particular event was caused by global climate disruption, but we expect events of this type to increase in frequency as a result of global climate disruption.”
I have been documenting here that hurricanes, tornadoes, floods, droughts, etc. are not increasing in frequency. The big lie marches on relentlessly. It is about power and control – not science.