Award: OCE-1260164

On 30 October 1988, a team of scientists from the University of Hawaii established Station ALOHA (22?45?N, 158?W) as an open ocean observatory for physical, biogeochemical, and ecological investigations. ALOHA is an acronym for A Long-term Oligotrophic Habitat Assessment, the stated mission of the National Science Foundation-supported Hawaii Ocean Time-series (HOT) program. On approximately monthly intervals since then, scientists, engineers, students, and technicians from around the world have embarked on more than 300 expeditions to observe and record both natural and human-induced variations in ecosystem structure and function at this remote open ocean location. Such studies have identified key processes and patterns associated with biogeochemical cycles of carbon and associated bioelements, including those controlled by time-variable plankton biology, air-sea interactions, and vertical and horizontal fluxes of nutrients. Located approximately 100 km north of Oahu, Hawaii, Station ALOHA has become a global ocean reference point for tracking oceanic and ecosystem dynamics, and it has already had a major impact on how we study, interpret, and model biogeochemical processes in oligotrophic ecosystems. Many of the general characteristics of the North Pacific Subtropical Gyre (NPSG) habitat were known prior to the establishment of Station ALOHA, but other features were either poorly understood or not yet discovered. For example, the three major groups of microorganisms that are numerically dominant members of the NPSG ecosystem (i.e., Prochlorococcus spp., the SAR 11 clade of Alphaproteobacteria, and planktonic archaea) were all discovered after the establishment of Station ALOHA in 1988. Furthermore, the origins of the marine -omics revolution postdate the creation of HOT. From the beginning, HOT was conceived as a research vessel-based sampling and observation program. Over the years, additional remote-sensing assets including satellites, floats, moorings, autonomous underwater vehicles, bottom-moored sediment traps, and a deep-sea cabled observatory have enhanced the value of the core measurement program. The resulting data, which are all publicly available (http://hahana.soest.hawaii.edu/hot/hot_jgofs.html), have already helped to define major patterns and time-varying dynamics associated with ocean hydrography, biogeochemistry, and controls on primary production and export. The sustained measurements at Station ALOHA provide some of the only multidecadal ocean observations from which we can gauge future changes to the ocean. Over the past three decades nearly 800 scientific papers and reports have highlighted spatial and temporal variability in the NPSG ecosystem from surface waters to the deep sea, the development of novel methods and instrumentation for investigations of biogeochemistry and ecology, and selected data synthesis and modeling efforts. These contributions challenge some existing paradigms and continue to transform our understanding of coupled physical-chemical-biological interactions and the impacts of climate change on marine ecosystems. In recognition of these ?historic and visionary accomplishments,? the American Society for Microbiology recently designated Station ALOHA as a Milestones in Microbiology Site, one of only 15 institutions, scientists, or locations where significant contributions toward advancing the science of microbiology have been achieved (https://www.asm.org/index.php/about-microbiology/history-4). With each additional expedition to Station ALOHA, the time series becomes more valuable for the detection and interpretation of ecosystem variability. The observations and experimentation conducted at Station ALOHA have contributed to the growing base of knowledge in ways that could not have been predicted when the program began in 1988. Ultimately, the creation and dissemination of scientific knowledge must be a primary motivation if a long-term time-series program is to remain vibrant and relevant. The assessment of NPSG ecosystem dynamics is still a work in progress. We need to sustain the current pace of new discovery and further contribute to our understanding of the sea around us. Last Modified: 10/22/2019 Submitted by: David M Karl