The Equinoxes and Solstices As Viewed From Space
Credit: NASA Earth Observatory
The four changes of the seasons, related to the position of sunlight on the planet, are captured in this view from Earth orbit.
Source: earthobservatory.nasa.gov
Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio
James Hansen and colleagues use the bell curve to show the growing frequency of extreme summer temperatures in the Northern Hemisphere, compared to the 1951 to 1980 base period.
The mean temperature for the base period is centered at the top of the green curve, while hotter than normal temperatures (red) are plotted to the right and colder than normal (blue) to the left.
By 1981, the curve begins to shift noticeably to the right, showing how hotter summers are the new normal. The curve also widens, due to more frequent hot events.
Source: nasa.gov
