Length of day and its effects on Earth systems

¶ … sun lit side of the earth over a span of a year period, one can make general observations in regards to the distribution of solar energy throughout the period. The four slides show more of the southern hemisphere lit up during all periods examined. Only in June is the land above 60 degrees north visible. This shows that the north pole receives less overall solar energy throughout the year. The southern hemisphere receives more solar energy later in the year, between September and December. By September, South America has moved much closer to the center of the screen, showing much more of the lower hemisphere being lit by the sun. By December, the 90th degree parallel can be seen as lit up by the sun. In this shot, North and South America are the most visible and lay directly under the sun. These two continents lay between the 60th and 120th degrees longitude. In June near the summer equinox, the equator is in the center of the screen, with the two poles not visible and not fully lit by the energy of the sun. However, over the course of the year and towards the winter solstice, the equator slowly moves north, which then exposes much more of the southern hemisphere.

Part 2

Iceland is extremely high on the latitude scale in terms of it being one of the northernmost nations on the planet. Being so close to the north pole means that during the winter months, the nation of Iceland receives very few hours of sunlight. In December, the country receives the least amount of sunlight, spending roughly about 4 hours a day in daylight. Thus, the fraction of the day spent in the sun is about 4/24ths, or 1/6th of the day spent lit up by the sun. This hourly number slowly grows as the seasons change, with about ten or so hours of daylight. Thus, 5/12th of the time is spent under the sun's rays during the month of March. June provides great periods of sunlight for the northern nation. During the summer months of June, most of Iceland witnesses a staggering 19 or 20 hours of sunlight, with only a few hours of darkness. Thus, this fraction of the day spent in the sun is around 4/5ths. September once again witnesses the onset of more darkness, with a percentage of the daylight similar to the month of March.