|Department of Oceanography|
University of Hawaiʻi at Mānoa
Marine Science Building
1000 Pope Road
Honolulu, HI 96822
|Phone:(808) 956-2613 |
Website: The Hawco Lab
Phytoplankton are the foundation of marine food webs, but their growth depends on supply of over a dozen nutrients to the upper ocean where photosynthesis can occur. Many of these are deemed ‘micronutrients’ and represent less than 1 part per billion of the atoms in seawater. Micronutrient scarcity has forced phytoplankton to develop unique strategies to acquire these resources, or to reduce their biochemical dependence on them, but these efforts are not always enough: throughout the oceans, micronutrient limitation of phytoplankton growth controls the size of marine ecosystems and influences the global carbon cycle. Many mysteries about these micronutrients remain, particularly for metals like iron, cobalt, and zinc whose chemistry in seawater is complex. My research focuses on the global cycles of these elements in the oceans, how they influence the growth and evolution of phytoplankton lineages, and how their distribution would change in past or future climates.
Current Research Projects
Click here to see a completed list of Dr. Hawco’s publications.
Hawco NJ, McIlvin M, Bundy RM, Tagliabue A, Goepfert TJ, Moran D, Valentin-Alvarado L, DiTullio G, Saito MA. Minimal cobalt metabolism in the marine cyanobacterium Prochlorococcus. In Review.
Hawco NJ, Yang SC, Foreman RK, Funkey CP, Dugenne M, White AE, Wilson ST, Kelly RL, Bian X, Huang KF, Karl DM, John SG. Metal isotope signatures from lava-seawater interaction during the 2018 eruption of Kīlauea. In Review.
Wilson ST*, Hawco NJ*, Armbrust EV, Barone B, Björkman KM, Boysen AK, Burgos M, Burrell TJ, Casey JR, DeLong EF, Dugenne M, Dutkiewicz S, Dyhrman ST, Ferrón S, Follows MJ, Foreman RK, Funkey CP, Harke MJ, Henke BA, Hill CN, Hynes AM, Ingalls AE, Jahn O, Kelly RL, Knapp AN, Letelier RM, Ribalet F, Shimabukuro EM, Tabata RKS, Turk-Kubo KA, White AE, Zehr JP, John SG, and Karl DM. Kīlauea Lava Fuels Phytoplankton Bloom in the North Pacific Ocean. Science, 365, 1040–44, 2019. *co-first author.
Hawco NJ and Saito MA. Competitive Inhibition of cobalt uptake by zinc and manganese in a Pacific Prochlorococcus strain: insights into metal homeostasis in a streamlined oligotrophic cyanobacterium. Limnology and Oceanography, 63 (5), 2229-2249, 2018.
Hawco NJ, Lam PJ, Lee JM, Ohnemus DC, Noble AE, Wyatt NJ, Lohan MC, and Saito MA. Cobalt scavenging in the mesopelagic ocean and its influence on global mass balance: Synthesizing water column and sedimentary fluxes. Marine Chemistry, 201 (20), 151-166, 2018.
Tagliabue A, Hawco NJ, Bundy RM, Landing WM, Morton PL and MA Saito. The role of external inputs and internal cycling in shaping the global ocean cobalt distribution: Insights from the first cobalt biogeochemical model. Global Biogeochemical Cycles, 32, 594-616, 2018.
Hawco NJ, Ohnemus DC, Resing JR, Twining BS, and Saito MA. A cobalt plume in the oxygen minimum zone of the Eastern South Pacific. Biogeosciences, 13 (20), 5697, 2016.