Observatory Research Projects and Collaborations
Ongoing research projects and collaborations at BHO cover a wide range of topics related to our long-term climate record, and these activities are supported by staff and professional scientists as well as high-school and college student interns and other volunteers. Listed below is a sample of current projects.
Wind Speed Decrease
The annual mean wind speed has been dropping steadily since around 1980, and BHO staff are investigating the possible causes with our extensive data sets. We are also working in collaboration with a scientist from Spain, Cesar Azorin-Molina, who specializes in this topic in Western Europe where decreasing wind speeds are also being observed. Among the potential causes of the wind speed drop being investigated are the regional regrowth of vegetation, which can slow surface wind speeds, or shifts in the storm track, which may be caused by changes in the general circulation in response to climate change.
Bright Sunshine Trends
A Campbell-Stokes sunshine recorder has been in use to measure bright sunshine duration at BHO since 1886, and this represents the longest such record of sunshine in North America. Trends in recent decades are believed to be related to global dimming (in the 1970s and 1980s) and subsequent global brightening (since 1990) due to the increase and the later reduction of atmospheric aerosols over these decades. Work is in progress to distinguish the combined effects of clouds and aerosols on the sunshine record. We are investigating this topic in collaboration with other researchers in Spain. In addition, recently tabulated daily sunshine data have been studied to assess the presence of climate change signals, and a journal article based on this work was recently published in the Bulletin of the American Meteorological Society.
Daily Climate Data Digitization
Extensive work is in progress to transfer more than 135 years worth of primary daily data observations including maximum and minimum temperature, precipitation, snowfall, snow cover, wind speed, sunshine and other parameters. This process will fill gaps and remove inconsistencies in the existing data base and to begin the process of digitizing data that has never been tabulated before. The objective is to generate the best possible collection of BHO daily climate data to support ongoing and future climate research projects and educational activities. In addition, work is in progress to conserve and to scan our collection of historic observation books.
In collaboration with Dr. Alan Kafka, the Director of Boston College’s Weston Observatory, Blue Hill purchased and installed a “Raspberry Shake” seismograph in Fall 2019. This seismograph provides a new site at the Blue Hill Observatory for monitoring earthquakes around the world and in the local area. Small differences in the amplitude and arrival times of the waves produced by earthquakes in distant places that travel around and through the Earth provide information about characteristics of the earthquakes and about the interior of the Earth. As of early 2020, several earthquakes have been measured by the instrument at Blue Hill, and the results are being compared with observations from other seismographs in New England and around the world.