Comparison to all years
The red and blue lines show data plotted for each day of the specified year, over the month ranges shown. The other lines and shadings show data with respect to the climatological period indicated. This climatological period excludes the particular year for which the plot is shown. Each day has its own specific climatological values. The thin black lines show the maximum and minimum for each day found in the climatology. The light gray shading indicates the 10th and 90th percentile values, while the dark shading shows the 30th and 70th percentile values for the climatology. Finally, the thick black line indicates the 50th percentile value, or the median, of the climatology. A record value is indicated when the red or blue line is located outside one of the thin black lines.
The Type I PSC and Type II PSC lines refer to temperatures at which nitric acid (HNO3) and water (H2O) saturate to form nitric acid trihydrate particles and water ice particles respectively. These saturation temperatures depend on the concentration of water and nitric acid in the stratosphere (the approximate values are noted at the top left).