SINE

This not hot air. It is getting more warm and dry in Southwest (and everywhere else) over past 11,000 years, since the end of the most recent ice age. Your guy Scott Elias did research and says:

Scott A. Elias, The Ice-Age History of the Southwestern National Parks (Washington, 1997), pp. 3, 5, 47, 58:

"Although glacial ice did not cover the American Southwest, regional climates were greatly affected by global cooling during glaciations. In addition, the ice sheets that covered more northerly regions forced changes in atmospheric circulation. It is thought that the jet stream split in two as it met the obstacle of ice sheets that were perhaps several miles thick. One branch flowed north of the ice sheets; the other branch flowed south, bringing increased moisture to the Southwest.

"Some lowland regions [of the Southwest,] notably in the Great Basin, developed large pluvial lakes during Pleistocene [older] glaciations. With the exception of Great Salt Lake and some other smaller basins, these lakes dried up ... [since the most recent ice age,] but they left behind sediments in lake beds and ancient shorelines and downwind dune fields that are still visible along hill slopes.

[The cooler/moister ice age climate did not permit desert:] The desert vegetation that covers most lowland regions in the American Southwest today was virtually nonexistent in the Pleistocene. In its place, ....the juniper-piñon woodland of the modern middle-elevation highlands spread out like a vast, green carpet across the lowlands, from the Chihuahuan Desert in the east to the last outpost of land on the west coast, Catalina Island. During the last ice age, coniferous woodlands covered most of the Southwest; [though] desert plants were scattered far and wide, living in pockets of arid climate.… Large ice-age mammals roamed the [area] ..., ranging from the majestic (such as the Columbian mammoth ) to the bizarre (such as the giant ground sloths). At the end of the [most recent] ice age, human beings entered the Southwest [about 11,000 years ago. Although it has been getting warmer ever since, it is interesting to note that desert in the Southwest is the exception, not the rule.] Most of the past 125,000 years [has been] spent in [cool] glacial intervals, not in [warm] interglacial periods such as ... [we enjoy]. In fact, geologists reckon that glacial periods took up more than 90% of the last 1.7 million years.

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