Solar radiation is the fuel which moves the weather. Almost all energy which moves the atmosphere comes from the sun.
The amount of sunlight and radiation reaching the earth is different, depending on latitude (North /South), the seasons and the daylength.
On the right handside, you see two meteogramm "AIR" ( which shows ground + air layers) of Manaus (Brazil) and Oslo (Norway) for comparison. The meteogramms show the forecasts of the 12.Aug.2010. You can see the radiation in the lowest chart as a yellow curve. The maximum values of the radiation differentiate heavily. With higher solar altitude (Manaus), the radiation is higher as with a lower angle of insolation (Oslo).