Brian Lear on WNYC and now we continue our WNYC centennial series a hundred years of a

hundred things we're gonna get to it a hundred years of air conditioning but just to recoup Monday segment, the 10

mormous years in the historical record have occurred in the last decade.

We spoke about it when we did a crawl through temperature averages over the last hundred years

as part of the series on Monday.

Here's just 20 seconds of Monday's guest to help take us to the air condition and conversation climate

scientist Michael E. Mann, professor and director of the Center for Science

Sustainability in the media at the University of Pennsylvania as he explained to us just how rare the

current temperature curve is and why it wouldn't happen without human-caused climate change.

People say, oh, well, maybe we're just unlucky.

We've had a number of warm years, you know, it's an unlucky role of the climate dice.

You can calculate in the absence of human-caused warming warming how likely something like that would be and we're talking like one in 50,000 year event

Something that is extremely unlikely to have been observed in the absence of human caused warming.

So that was thing five on Monday show.

Now we're up to thing six, which yes, follow suit and is air conditioning.

100 years ago in 1924, a department store in Detroit

called J.L. Hudson's became the first

to use air conditioning to cool its stores.

Sales ticked up immediately and the demand for air-conditioned public spaces

soared, most notably movie theaters. Over the decades, air conditioning became ubiquitous in American homes, as we know, also transportation, also other shared spaces.

But it also represented a problem.

The chemicals used in the cooling process

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