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  • Writer's pictureBenay Hicks

Siobhan Powers: Book Harvest AmeriCorps Member and NOAA Contributing Author!

April 13, 2023

Siobhan Powers, Book Harvest’s NC LiteracyCorps member, used to work predominately in surveying and data analysis. Her most recent role was at the National Oceanic and Atmospheric Association where she created a survey and consolidated database for NOAA Citizen Science projects across the country!

Siobhan is an exceptional member of the Book Babies team, and we want to highlight some of her incredible work with the NOAA. She is currently interviewing NOAA volunteers from around the country and producing articles about their work. Below is her latest piece, published on April 10: Trekking to track down the exact locations of survey benchmarks. It was originally published here.


April 10: Trekking to track down the exact locations of survey benchmarks

Volunteer: Philip Melcher

Project: GPS on BenchMarksLocations: California, Oregon, Hawai‘i, Puerto Rico

Year Participated: 2019-2022

Philip Melcher is one of the GPS on BenchMarks program’s most prolific volunteers. Since 2019, he has submitted more than 4,700 hours of GPS observations. In the process, he traveled thousands of miles by truck, bike, kayak, and foot — all to observe important survey marks, called “benchmarks,” that are essential for modernizing our National Spatial Reference System. In his career as a civil engineer specializing in agriculture and irrigation districts, Philip uses benchmarks while surveying land for clients. Due to many factors, such as the surface of the Earth changing over time, many of these benchmarks are no longer accurate. Learn more about why Philip participates in this program.

Why do you participate in this project?

I originally started participating in this project when one of our Registered Civil Engineers requested help from land surveyors to get GPS observations on six benchmarks that were scattered around the Central Valley of California with the new GEOID 18 model. I had the time and equipment to occupy and submit these needed data to the National Geodetic Survey. Having worked in the Central Valley for 17 years, I utilized these benchmarks frequently for horizontal and vertical positions (longitude, latitude, and elevation). I knew through experience, they were not correct. Through this project, I found an opportunity to show what I see through the GPS on BenchMarks program.

What has been the highlight of your work as a citizen scientist?

As a citizen scientist, the highlight for me has been my ability to gather these data throughout the Pacific Southwest. Although I’m not a scientist or geodesist, I’m excited that I can provide the data that the National Geodetic Survey needs to improve the National Spatial Reference System. Finding these benchmarks is always an adventure, whether hiking, biking, running, kayaking, or swimming through a shiver of leopard sharks, and reading 50 to 100 year old descriptions of how to find them.

Has your participation affected you? How have you benefited from being involved?

I have an overall sense of accomplishment knowing that the data I provide will help with science, the communities I work in, and will be of benefit to all surveyors. I can see how everything is related at a macro level. The ultimate benefit will be after the modernized National Spatial Reference System is in place.

Philip Melcher, a civil engineer who volunteers with NOAA’s GPS on BenchMarks project, collects GPS observations on Mt. Whitney, which holds the highest survey mark in the contiguous United States. (Image credit: Courtesy of Philip Melcher)


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