The sunrises and sunsets in North Park are absolutely GORGEOUS. Even though they are commonplace, I try to appreciate them each and every single day.
Here's a little blurb I found online about how and why we see different colors when the sun is rising and setting...
At dusk and dawn the colors of the sky change and the first portion of the visible spectrum is what appears to the viewer. During these times of the day the sun is positioned at a different angle to the earth than during the normal daytime. Because of this angle, the longer wavelengths are the ones that reach the eye. The blue and other shorter wavelengths are scattered millions of times and do not reach the viewer. When the sun does not shine directly on a certain portion of the earth there are more gas molecules between the viewer and the sun. Therefore, the normal blue color of he sky is no longer visible because the short wavelengths of blue and green are scattered millions of times and do not reach the viewer. Therefore the longer wavelengths that couldn't be scattered as many times are able to now hit the viewer in a more direct way.