Insolation- is the amount of the sun's energy that reaches a point on the earth's surface. This energy varies based upon the time of year and the latitude. For example for us, northern hemisphere, during the winter we receive less energy because we are tilted away from the sun. In fact the North Pole gets no direct sunshine during the winter.
Let's look at this skew-T diagram: this diagram shows the relationship of atmospheric temp (solid line) to dewpoint temp (dotted line). Few things to take note-dew point is always to the left of temp, as air moves up in the atmosphere its temperature decreases and moves away from the dewpoint. Also, when temperature and dewpoint are close together the air's relative humidity is high, clouds can form and precipitation can also occur.
