我们这里关键要看这句话(我看了攻略才知道的,这道题的确难):
Within about a
Line millimeter of the water, air temperature is close to that of the surface water, and the air is nearly saturated with water vapor
But the differences, however small, are
crucial, and the disequilibrium is maintained by air near
the surface mixing with air higher up, which is typically
appreciably cooler and lower in water-vapor content.