# Relationship between insolation and lines of latitude

### Insolation | EARTH Earth in the Future

Earth-Sun relationships cause changes in the amount of insolation received day to day Low latitudes are those locations found between the Equator (0 degrees N/S) .. Think of the axis as an imaginary line extending from pole to pole and. The Earth orbits around the Sun with its spin axis (the line connecting the If the tilt were 0°, there would be no real difference between winter and Graph showing the variation of insolation with latitude in summer, winter, and the annual . The Earth's axis makes an angle of 66 with the plane of its orbit round the sun, has a greater influence on the amount of Insolation received at different latitudes.

Insolation input of solar energy as a Function of Latitude and Season The motivation for this material was when a friend told of seeing a video in which it was revealed that open water had been found at the North Pole. The video presented this as confirmation of global warming.

WORLD GEOGRAPHY- GS: CHAPTER-5 : Latiitude and Longitude Lines(अक्षांश-देशांतर रेखाएं ) अध्याय-5

The open water at the North Pole had been viewed by a couple of American scientists who were not meteorologists who journeyed on a commercial tour on a Russian ice-breaker in the summer time. The fact that it was summertime and that the Russians were taking customers on a regular basis to the North Pole should have alerted them that open water at the North Pole was not that unusual. But if one has a mindset concerning catastrophic global warming any observation that can be construed as evidence for global warming is accepted as evidence for global warming.

Open water at the North Pole may have to do with ocean and wind currents as well as temperature. However it is not widely known that the North Pole in the summer time was never deficient in solar warming. The input of radiant energy from the Sun is called insolation.

Earlier, we mentioned the Solar Constant — a measure of the amount of solar energy reaching Earth. In reality, this value is not a constant because the Sun is a dynamic star with lots of interesting changes occurring. One of the best known of these changes is the solar cycle related to sunspots.

## Insolation

Sunspots are dark regions on the surface of the Sun related to intense magnetic activity, and measurements have shown that the greater the number of sunspots, the greater the energy output of the Sun. Early observations of these sunspots revealed a pronounced cyclical pattern to them, varying on an year cycle, as shown below. Sunspot History and Solar Constant comparing number of sunspots per calendar year. Bice Here, in blue, we see the annual number of sunspots and in red we see the reconstructed solar intensity or Solar Constant.

The reconstruction is made by studying the relationship between sunspot number and solar intensity in the last few decades where we have good direct measurements of the solar intensity — this provides a relationship that is fairly simple and directly proportional. Higher sunspot numbers correspond to higher solar intensity. Figure 6i-2 describes the change in the length of day for locations at the equator, 10, 30, 50, 60, and 70 degrees North over a one-year period.

The illustration suggests that days are longer than nights in the Northern Hemisphere from the March equinox to the September equinox.

### Insolation and Temperature

Between the September to March equinox days are shorter than nights in the Northern Hemisphere. The opposite is true in the Southern Hemisphere.

The graph also shows that the seasonal winter to summer variation in day length increases with increasing latitude. Figure 6i-3 below describes the potential insolation available for the equator and several locations in the Northern Hemisphere over a one-year period.

The values plotted on this graph take into account the combined effects of angle of incidence and day length duration see Table 6h Locations at the equator show the least amount of variation in insolation over a one-year period.

These slight changes in insolation result only from the annual changes in the altitude of the Sun above the horizon, as the duration of daylight at the equator is always 12 hours. The peaks in insolation intensity correspond to the two equinoxes when the Sun is directly overhead.

The two annual minimums of insolation occur on the solstices when the maximum height of the Sun above the horizon reaches an angle of