Explain how the cold California current contributes to the dryness of Southern California, Arizona, and New Mexico

The correct answer to this open question is the following.

The cold California current contributes to the dryness of Southern California, Arizona, and New Mexico in that the cooler water that comes from California is slow to evaporate.

This California current comes from the Pacific Ocean, from British Columbia, Canada, to the Baja California peninsula in México. It produces a cooler current because this current comes from Alaska. This current makes other states such as New Mexico and Arizona to have dryness that affects the climate in these regions.

The cold California current keeps everything dry because with low temperature comes with cold atmosphere, which makes Southern California, Arizona and New Mexico experience warmer temperature due to low humidity and evaporation. Meanwhile, the upper elevations have high humidity and evaporation, which means more rain and cooler compare to those in the valleys.