General Information

The primary sampling and data collection site is located on the northern slope of the Mauna Loa volcano. The observatory was constructed in 1956 and has been continuously in operation since. The site provide access to clean air up to the stratosphere during the night, when down slope conditions exist.

mlo aerial photo

GPS Information

Latitude: 19.54° N
Longitude: 155.58° W
Elevation: 3397m (11,140ft)
Time Zone: HST (-10 GMT)


Day Night
Average Temperature: 9°C (48°F) 5°C (41°F)
Average Min Temperature: 4°C (39°F) 3°C (37°F)
Average Max Temperature: 12°C (54°F) 7°C (45°F)

Other Information

Average Precipitation: 1.5"/month
Average Station Pressure: 680 mbs.
Overall Winds: Mostly East and North-east Trades
Local Flows: Day-upslope; Night-downslope
Average Wind Speed: 5 m/sec (11mph)
Max Average Wind Speed: 20m/sec (45mph)