The Origin of the Atmospheric River
I did some digging into the phenomenon of atmospheric rivers and learned a bit about the atmospheric river (AR) currently underway in the Los Angeles area. Fun facts to share about the AR-
- On average, ARs provide 30-50 % of the annual precipitation to the west coast
- A strong AR transports 7.5 to 15 times the amount in water vapor as the average liquid water output at the mouth of the Mississippi River
- The AR is a normal feature of the global water cycle and there is one occurring somewhere on the Earth every day.
- An AR can be as much as 3200 km long and 400 to 600 km wide and flowing at 10,000 ft
- The AR is the result of moist tropical air transported to the upper latitudes as in the case of the Pineapple Express.
The graphic below is from the NOAA website on ARs and shows some general characteristics of an AR in play in California at present.
If weather is of interest to you, surfing through the various web sites put up by NOAA is worthwhile. NOAA does public outreach very well.