Measurements at the Mauna Loa Observatory stopped after the 2022 eruption of the Mauna Loa volcano, when lava flow crossed the access road and took out power lines to the facility. The observatory remains inaccessible by vehicle and without power from the local utility company.

Observatory staff has established limited solar power in four observatory buildings and restored approximately 33 percent of the measurements onsite, including the Global Monitoring Laboratory and Scripps critical CO2 records and other atmospheric measurements.

Media can contact: Theo Stein (303) 819-7409 ( or Karin Vergoth 303-632-6413‬ (


NWS logo National Weather Service Hilo, National Climatic Data Center

What does this program measure?

The Max/Min Temperature Unit records 24 hour Maximum/Minimum temperatures in degrees Fahrenheit. The Standard Rain gauge records 24 hour rainfall in hundreds of an inch.

How does this program work?

The data is measured manually by MLO personnel and recorded on standard government forms and the equipment is reset for the next 24 hour reading or observation.

  • A 20-cm rain gauge is recorded 5 times per week at MLO.
  • A 20-cm rain gauge is recorded 1 time per week at Kulani Mauka.
  • A rain gauge and tipping bucket are measured continuously at MLO.

Why is this research important?

Our cooperative program is a volunteer program involving the daily measurements of rainfall and temperature. The recorded data are sent to the National Climatic Data Center where they are archived as official government documents and produced as monthly publications.

Are there any trends in the data?

The National Climatic Data Center in Asheville, N. C. archives the data and as one of its missions, does research on long-term climatic changes which involve climatic trends.

How does this program fit into the big picture?

What is it's role in global climate change?

Same as above.

Comments and References

The true worth and importance of this program lies in its long historical and practical values. The cooperative program has proven its worth and can attest to a taxpayer savings of millions of dollars annually.

Lead Investigator(s):

Wilfred Laplante

MLO Contact(s):

David Nardini
808-933-6965 (x229)
Paul Fukumura
808-933-6965 (x223)

Web Site(s)


Date Started

May 24, 1956

Related Programs

NWS Rosa

NWS Meteorology Sensor
Temperature sensor
8 Inch Rain Guage at MLO
8" rain guage sampling tube
Dipping Stick For 8 Inch Rain Guage
Measuring rain
Measuring Rain at MLO
Measuring stick
Filling out the log book
Filling out the log book