A5023593359- Atmospheric and Environmental Gas Dynamics
- Methane Hydrates and Related Phenomena
- Marine and coastal ecosystems
- Atmospheric Ozone and Climate
- Climate variability and models
- Ocean Acidification Effects and Responses
- Oceanographic and Atmospheric Processes
- Atmospheric chemistry and aerosols
- Geology and Paleoclimatology Research
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Marine Biology and Ecology Research
- CO2 Sequestration and Geologic Interactions
- Air Quality and Health Impacts
- Geochemistry and Geologic Mapping
- Geological Studies and Exploration
- Carbon Dioxide Capture Technologies
- Air Quality Monitoring and Forecasting
- Indigenous Studies and Ecology
- Meteorological Phenomena and Simulations
- Nuclear Physics and Applications
- Marine and environmental studies
- Climate Change Policy and Economics
- Marine Bivalve and Aquaculture Studies
- Vehicle emissions and performance
National Institute of Water and Atmospheric Research
2015-2025
ISIS Neutron and Muon Source
2021
Rutherford Appleton Laboratory
2017
Charles River Laboratories (Netherlands)
2015-2017
Science and Technology Facilities Council
2014
Princeton University
2006-2011
University of California, Los Angeles
2003-2007
Planetary Science Institute
2007
NOAA Oceanic and Atmospheric Research
2006
Diamond Materials (United States)
2006
We synthesize estimates of the contemporary net air‐sea CO 2 flux on basis an inversion interior ocean carbon observations using a suite 10 general circulation models (Mikaloff Fletcher et al., 2006, 2007) and compare them to based new climatology difference partial pressure ( p ) (Takahashi 2008). These two independent reveal consistent description regional distribution annual mean sources sinks atmospheric for decade 1990s early 2000s with differences at level generally less than 0.1 Pg C...
Abstract. The global ocean is a significant sink for anthropogenic carbon (Cant), absorbing roughly third of human CO2 emitted over the industrial period. Robust estimates magnitude and variability storage distribution Cant in are therefore important understanding impact on climate. In this synthesis we review observational model-based transport ocean. We pay particular attention to uncertainties potential biases inherent different inference schemes. On scale, three data-based inventory now...
Getting a rise out of agriculture Methane, powerful and important greenhouse gas, has been accumulating nearly uninterruptedly in the atmosphere for past 200 years, with exception mysterious plateau between 1999 2006. Schaefer et al. measured methane's carbon isotopic composition samples collected over 35 years order to constrain cause pause. Lower thermogenic emissions or variations hydroxyldriven methane sink caused plateau. Thermogenic didn't resume subsequent rise. Instead, ongoing is...
Regional air‐sea fluxes of anthropogenic CO 2 are estimated using a Green's function inversion method that combines data‐based estimates in the ocean with information about transport and mixing from suite Ocean General Circulation Models (OGCMs). In order to quantify uncertainty associated owing modeled errors data, we employ 10 OGCMs three scenarios representing biases estimates. On basis prescribed storage, find global uptake 2.2 ± 0.25 Pg C yr −1 , scaled 1995. This error estimate...
The amount of the greenhouse gas methane in Earth's atmosphere is rising rapidly
We have constructed an inverse estimate of surface fluxes carbon dioxide using both atmospheric and oceanic observational constraints. This global is spatially resolved into 11 land regions ocean regions, calculated as a temporal mean for the period 1992–1996. The method interprets in situ observations concentration atmosphere with transport estimates from circulation models. Uncertainty modeled explicitly considered this inversion by suite 16 10 simulations. analysis, coupled river...
A time‐dependent inverse modeling approach that estimates the global magnitude of atmospheric methane sources from observed spatiotemporal distribution CH 4 , 13 C/ 12 C isotopic ratios, and a priori source strengths is presented. Relative to estimates, model calls for increased flux with strong spatial footprints in tropics Southern Hemisphere decreases Northern Hemisphere. The ratio observations suggest an unusually high swamps (∼200 ± 44 Tg /yr) biomass burning (88 18 relatively low...
Abstract. We show here an updated estimate of the net land carbon sink (NLS) as a function time from 1960 to 2007 calculated difference between fossil fuel emissions, observed atmospheric growth rate, and ocean uptake obtained by recent model simulations forced with reanalysis wind stress heat water fluxes. Except for interannual variability, appears have been relatively constant at mean value −0.27 Pg C yr−1 1988, which it increased abruptly −0.88 (−0.77 −1.04) new −1.15 1989 2003/7 (the...
We use an inverse method to estimate the global‐scale pattern of air‐sea flux natural CO 2 , i.e., component due carbon cycle that already existed in preindustrial times, on basis ocean interior observations dissolved inorganic ( DIC ) and other tracers, from which we Δ C gasex observed is gas exchange . employ a suite 10 different Ocean General Circulation Models (OGCMs) quantify error arising uncertainties modeled transport required link surface fluxes. The results contributing OGCMs are...
Abstract. The Southern Ocean (44–75° S) plays a critical role in the global carbon cycle, yet remains one of most poorly sampled ocean regions. Different approaches have been used to estimate sea–air CO2 fluxes this region: synthesis surface observations, biogeochemical models, and atmospheric inversions. As part RECCAP (REgional Carbon Cycle Assessment Processes) project, we combine these different quantify assess magnitude variability between 1990–2009. Using all models inversions (26),...
We report here the results from a coupled ocean‐atmosphere inversion, in which atmospheric CO 2 gradients and transport simulations are combined with observations of ocean interior carbon concentrations to provide jointly constrained estimate air‐sea air‐land fluxes. While data have little impact on regional flux estimates, inclusion drives substantial change terrestrial estimates. Our indicate that tropical southern land regions together large source carbon, 77% probability their aggregate...
Several lines of evidence point to an increase in the activity terrestrial biosphere over recent decades, impacting global net land carbon sink (NLS) and its control on growth atmospheric dioxide (ca ). Global gross primary production (GPP)-the rate fixation by photosynthesis-is estimated have risen (31 ± 5)% since 1900, but relative contributions different putative drivers this are not well known. Here we identify rising CO2 concentration as dominant driver. We reconcile leaf-level...
Abstract. Accurate national scale greenhouse gas source and sink estimates are essential to track climate mitigation efforts. Inverse models can complement inventory-based approaches for emissions reporting by providing independent underpinned atmospheric measurements, yet few nations have developed this capability carbon dioxide (CO2). We present results from a decade-long (2011–2020) inverse modelling study New Zealand, which suggests persistent in Zealand’s terrestrial biosphere (-171 ±...
We present a time‐dependent inverse modeling approach to estimate the magnitude of CH 4 emissions and average isotopic signature combined source processes from geographical regions based on observed spatiotemporal distribution 13 C/ 12 C ratios in . The estimates sources are used partition regional into three groups their signatures. Compared with bottom‐up estimates, call for larger fluxes tropics (266 ± 25 Tg /yr) southern extratropics (98 15 reduced northern (252 18 /yr). observations...
Abstract. Air–sea CO2 fluxes over the Pacific Ocean are known to be characterized by coherent large-scale structures that reflect not only ocean subduction and upwelling patterns, but also combined effects of wind-driven gas exchange biology. On largest scales, a large net influx into extratropics is associated with robust seasonal cycle, efflux from tropics substantial interannual variability. In this work, we have synthesized estimates air–sea flux variety products, drawing upon approaches...
The future status of the surface ocean around New Zealand was projected using two Earth System Models and four emission scenarios. By 2100 mean changes are largest under Representative Concentration Pathway 8.5 (RCP8.5), with a +2.5°C increase in sea temperature, decreases mixed layer depth (15%), macronutrients (7.5–20%), primary production (4.5%) particle flux (12%). Largest macronutrient declines occur eastern Chatham Rise subantarctic waters to south, whereas dissolved iron increases...
Abstract. We present 60 years of Δ14CO2 measurements from Wellington, New Zealand (41° S, 175° E). The record has been extended and fully revised. have used to evaluate the existing replace original where warranted. This is earliest direct atmospheric records rise 14C bomb spike subsequent decline in as moved throughout carbon cycle increasing fossil fuel CO2 emissions further decreased Δ14CO2. initially large seasonal 1960s reduces amplitude eventually reverses phase, resulting a small...
Measurements of atmospheric O 2 /N ratios and CO concentrations can be combined into a tracer known as potential oxygen ( APO ≈ + ) that is conservative with respect to terrestrial biological activity. Consequently, reflects primarily ocean biogeochemistry circulation. Building on the work Stephens et al. (1998), we present set observations for years 1996–2003 unprecedented spatial coverage. Combining data from Princeton Scripps air sampling programs, includes new collected ships in...
aEstimates have been corrected so that river carbon flow is manifested as a land sink and preindustrial ocean source of 0.45 PgC yr À1 (see auxiliary material).Contemporary air-sea fluxes (F contemp = F preindust + anthro ) scaled to the 1992 -1996 period by assuming anthropogenic component proportional atmospheric concentration perturbation, but air-land are not scaled.Original estimates, uncorrected for unscaled in time, given parentheses.''IPCC-TAR 90s'' estimate Prentice et al. [2001]...
Abstract. Using ocean carbon data from global datasets, we have developed several multiple linear regression (MLR) algorithms to estimate alkalinity and dissolved inorganic (DIC) in the intermediate deep waters of Southern Hemisphere (south 25° S) only hydrographic (temperature, salinity oxygen). A Monte Carlo experiment was used identify a potential density (σθ) 27.5 as an optimal break point between two regimes with different MLR algorithms. The provide good DIC (R2=0.98) (R2=0.91),...
The threat posed by ocean acidification (OA) to the diversity and productivity of New Zealand marine ecosystems is assessed in a synthesis published trends impacts. A 20-year time series Subantarctic water, national coastal monitoring programme, provide insight into pH variability, context for experimental design, modelling projections. review potential impact changes carbonate system on major phyla waters confirms international observations that calcifying organisms, particularly their...
Abstract. We present an analysis of a 39-year record continuous atmospheric CO2 observations made at Baring Head, New Zealand, filtered for steady background mole fractions during southerly wind conditions. discuss relationships between variability in the time series and regional to global carbon cycling. Head is well situated sample air that has been isolated from terrestrial influences over Southern Ocean, experiences extended episodes strong winds with low variability. The reveals average...
Abstract. Tree ring Δ14C data (Reimer et al., 2004; McCormac 2004) indicate that atmospheric varied on multi-decadal to centennial timescales, in both hemispheres, over the period between AD 950 and 1830. The Northern Southern Hemispheric records display similar variability, but from alone is it not clear whether these variations are driven by production of 14C stratosphere (Stuiver Quay, 1980) or perturbations exchanges carbon reservoirs (Siegenthaler 1980). As sea-air flux 14CO2 has a...
Abstract. The global ocean is a significant sink for anthropogenic carbon (Cant), absorbing roughly third of human CO2 emitted over the industrial period. Robust estimates magnitude and variability storage distribution Cant in are therefore important understanding impact on climate. In this synthesis we review observational model-based transport ocean. We pay particular attention to uncertainties potential biases inherent different inference schemes. On scale, three data based inventory now...