The fastest divers you’ve ever seen: installation of a climate monitoring station at Pagan Island

Text and video by Noah Pomeroy

I wish we could actually move as fast as we do in this video! In reality, this time-lapse video captures a scuba dive that took place on April 23 over about one hour in real time during a recent Pacific Reef Assessment and Monitoring Program (Pacific RAMP) research cruise in the Mariana Archipelago. This video shows the Climate and Ocean Change Team of the PIFSC Coral Reef Ecosystem Division (CRED) establishing a 15-m-deep climate monitoring station at Pagan Island in the Commonwealth of the Northern Mariana Islands (CNMI).


This site and other climate monitoring stations feature a variety of instrumentation, including subsurface temperature recorders (STRs), autonomous reef monitoring structures (ARMS), calcification accretion units (CAUs), and bioerosion monitoring units (BMUs). These instruments and monitoring installations provide oceanographic and ecological information about coral reef ecosystems. Seawater temperature is measured by STRs, calcification and bioerosion rates are determined by CAUs and BMUs, and cryptic biodiversity is evaluated by the analysis of invertebrate communities found living within ARMS.

The work at each station involves other activities in addition to the installation of instruments. During this dive, we completed a survey of rugosity, or habitat complexity, to document the physical relief of the reef structure. We also performed a photoquad survey, taking photographs along a transect to document the benthic reef community. Water samples were collected to assess the carbonate chemistry of water at the reef and at the surface above it.

Conducting this much work during one dive requires a lot of pre-dive planning and in-water choreography. Before beginning such a scuba dive, each diver identifies the tasks that he or she will complete and makes sure to have all the necessary tools and instruments. Although the team works to execute the dance as planned, unexpected challenges are common underwater. Heavy surge (the back and forth motion of water due to frequent waves) or a very hard substrate can make installing instruments and conducting a reef survey difficult.

Climate monitoring stations are one component of the broad National Coral Reef Monitoring Plan (NCRMP) of NOAA’s Coral Reef Conservation Program (CRCP). The NCRMP philosophy is to collect a standard suite of oceanographic and ecological information throughout each of NOAA’s jurisdictions to establish baselines and assess temporal and spatial variability in these coral reef ecosystems caused by global climate change and ocean acidification.

Ocean acidification is the changing of the carbonate chemistry of Earth’s oceans due to absorption of carbon dioxide (CO2). This absorption changes their delicate chemical balance, making it difficult for calcifying organisms, such as corals, mollusks, and shellfishes, to produce their carbonate skeletons. Information gathered at climate monitoring stations will be used by CRED staff to examine how the temperature and chemistry of the waters surrounding reefs vary over time and space and how those changes effect the fishes, corals, algae, and other organisms of the coral reef ecosystems at those sites.

The CRED so far has established climate monitoring stations in the CNMI and Guam, at Wake Island, and throughout the Hawaiian Archipelago. In 2015, the CRED will establish stations in American Samoa and at islands and atolls that make up the Pacific Remote Islands Marine National Monument. Support for these climate stations as part of NCRMP comes from the CRCP and the NOAA Ocean Acidification Program.

Four scuba divers from the PIFSC Coral Reef Ecosystem Division are featured in this video: Jeanette Clark, Russell Reardon, Charles Young, and Noah Pomeroy.


This entry was posted in coral reef ecosystem and tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , . Bookmark the permalink.