The marine cyanobacterium Synechococcus elongatus clone CCMP1629 was grown in a continuous culture system on a 14:10 light-dark cycle under either nitrate-limited or nutrient-replete conditions, a photoperiod irradiance of either 50 or 300 micro-mol photons per square meter per second, partial pressures of either 400 or 1000 ppm CO2, and temperatures ranging from 20 to 45 degrees Celsius. Growth rates, photosynthetic rates, respiration rates, C:N ratios, C:Chlorophyll-a ratios, productivity indices, Fv/Fm ratios, and the initial slope and light-saturated asymptote of short-term photosynthesis-irradiance curves are reported.