The 2022 eruption of the Mauna Loa volcano cut off road access to the Mauna Loa Baseline Observatory. Construction on the temporary Mauna Loa Access road was completed on 26 March, 2026.

At this time, there is no site access for the general public to the Mauna Loa Observatory and NOAA has not yet established a public opening date. GML and scientific partners are working together to bring mission critical scientific projects back online. It is still unclear when utility infrastructure will be replaced and power re-established to the site.

We will provide another update as more information becomes available.

Media contact: Theo Stein at (303) 819-7409 or theo.stein@noaa.gov.

Organization(s):

NOAA logo National Oceanic and Atmospheric Administration (NOAA), Earth System Research Laboratory (ESRL)

What does this program measure?

The Pollak CNC was a manual unit which used water vapor to produce counts in a Condensation Nuclei Counter (CNC). When the Pollak CNC was in operation at MLO, the TSI instrument (Thermo Systems Incorporated) was compared to the Pollak CNC once a day. The TSI unit is a continuous-expansion CNC (see CMDL Aerosols) by which particle number concentration is determined when particles are exposed the to a high super saturation of butanol vapor. This causes the particles to grow to a size where they can be detected optically and counted. The instruments in use have lower particle-size detection limits of 10-20 nm diameter.

How does this program work?

CMDL's General Operations Manual for our Aerosol Systems will describe precisely how these measurements took place. The project involved the Pollak Condensation Nuclei Counter, which measured daily at Mauna Loa Observatory.

Why is this research important?

Are there any trends in the data?

How does this program fit into the big picture?

What is it's role in global climate change?

Comments and References

This project is no longer active.

Lead Investigator(s):

none

MLO Contact(s):

Dr. John E Barnes
808-933-6965 (x222)

Web Site(s)

not applicable

Date Started

RETIRED

Related Programs

Air Quality Control
NOAA ESRL
Retired

Photographs:
OLD Pollak Instrument at MLO
Pollak