This graphic shows the Earth's postition on its orbit around the sun on May 1st with colors that indicate the northern hemisphere's seasons. Astronomically seen we are almost in the middle of spring: May is perhaps the typical month of spring all over the northern hemisphere: it's full spring now after a longer vernal period in mid latitudinal sites, and a short but intense spring begins now in polar regions. Popularly seen summer will begin next month. The changes in the sun angle decrease: the declination goes from about 15° to 22° in May, and will always be between 22° and 23.4° in June. It will be mid August when the angle will be 15° again: a change of less than 9° within more than 3 months. In the following 3 months the angle will change by 35°! This also means that all places on the northern hemisphere will have quite a stable high incoming solar energy for the next three months, which means that this hemisphere will be continually heated up. It would be interesting to know how much energy is exchanged within the hemishpere during this time and how much perhaps even across the equator.
