Datasets for 'Hydrological cycle amplification reshapes warming-driven oxygen loss in Atlantic Ocean'

Physical and biogeochemical variables from the NOAA-GFDL Earth System Model 2M experiments, and previously published observation-based datasets, used for the study 'Hydrological cycle amplification reshapes warming-driven oxygen loss in Atlantic Ocean'.National Science Foundation Career award 2042672; NSF Grant No. DGE-2039656; NASA Award 80NSSC20K0879;See readm

Data and code for 'Hydrological cycle amplification reshapes warming-driven oxygen loss in Atlantic Ocean'

Physical and biogeochemical variables from the NOAA-GFDL Earth System Model 2M experiments (pre-processed), previously published observation-based datasets, and code to reproduce figures from these datasets, used for the study 'Hydrological cycle amplification reshapes warming-driven oxygen loss in Atlantic Ocean'.National Science Foundation Career award 2042672; NSF Grant No. DGE-2039656; NASA Award 80NSSC20K0879hogikyanetal_sss_oxygen.py, oxygen_data.zip, README-hogikyan_oxygen.tx

Oxygen, Carbon, Heat: Explorations in Atmosphere-Ocean Interaction

This thesis describes three novel mechanisms of air-sea interaction. The first two chapters focus on the amplification of the hydrological (water) cycle as the climate system warms in response to a CO2 increase, which is realized as an amplification of freshwater flux (precipitation - evaporation) patterns. We find that this freshwater flux pattern leads to a redistribution of oxygen and carbon in the ocean, which modifies the previously recognized changes due to the atmospheric CO2 increase, warming, and circulation changes. The change in oxygen concentrations results from the change in sea surface salinity patterns which modifies the ocean circulation and heat uptake. The change in carbon concentrations results from the dilution or concentration of carbonate species (in parallel to salinity), and the same changes in heat uptake. The redistributions of oxygen and carbonate species in response to hydrological cycle amplification are comparable to the effect of global warming, which decreases both oxygen and carbon concentrations throughout the ocean. The third chapter provides a causal mechanism, for the first time, to link the change in sea surface temperature that develops during El Niño events to the change in temperature of the tropical free troposphere. The temperature of the free troposphere is primarily determined by the temperature profile followed by moist convection over the ocean (rising air above high sea surface temperatures). We isolate the part of the sea surface associated with convection (which is determined on thermodynamic rather than geographic grounds) and demonstrate that the El Niño surface temperature increase is driven by a decrease in surface wind speed which damps the evaporation rate. This result suggests a possible relationship between the zonal symmetry of the tropical atmospheric circulation, temperature of the free troposphere, and top-of-atmosphere energy budget

Why is El Nino warm?

Dataset constructed from GFDL-FLOR preindustrial control experiment run by Wenchang Yang ([email protected]) on Princeton University's tiger CPU. Processing by Allison Hogikyan ([email protected]) on Princeton University's tigress data processing node. June 2021

A Synthesis of Global Coastal Ocean Greenhouse Gas Fluxes

The coastal ocean contributes to regulating atmospheric greenhouse gas concentrations by taking up carbon dioxide (CO2) and releasing nitrous oxide (N2O) and methane (CH4). In this second phase of the Regional Carbon Cycle Assessment and Processes (RECCAP2), we quantify global coastal ocean fluxes of CO2, N2O and CH4 using an ensemble of global gap-filled observation-based products and ocean biogeochemical models. The global coastal ocean is a net sink of CO2 in both observational products and models, but the magnitude of the median net global coastal uptake is ∼60% larger in models (−0.72 vs. −0.44 PgC year−1, 1998–2018, coastal ocean extending to 300 km offshore or 1,000 m isobath with area of 77 million km2). We attribute most of this model-product difference to the seasonality in sea surface CO2 partial pressure at mid- and high-latitudes, where models simulate stronger winter CO2 uptake. The coastal ocean CO2 sink has increased in the past decades but the available time-resolving observation-based products and models show large discrepancies in the magnitude of this increase. The global coastal ocean is a major source of N2O (+0.70 PgCO2-e year−1 in observational product and +0.54 PgCO2-e year−1 in model median) and CH4 (+0.21 PgCO2-e year−1 in observational product), which offsets a substantial proportion of the coastal CO2 uptake in the net radiative balance (30%–60% in CO2-equivalents), highlighting the importance of considering the three greenhouse gases when examining the influence of the coastal ocean on climate.ISSN:0886-6236ISSN:1944-922