The tropical atlantic observing system

In the paper

“The magnitude of hurricane RI (increase in maximum wind speed of at least 25 kt in 24 h) has increased in the central and eastern tropical Atlantic since the 1980s (Balaguru et al., 2018).”

What the sources say

• Supported

  The paper’s Plain Language Summary states that rapid intensification is an increase of at least 25 knots in 24 hours and that its magnitude increased in the central and eastern tropical Atlantic during 1986–2015. Section 3.2 also states that the magnitude of hurricane RI increased in that region over the same period. (LLM, conf=0.94)

  cites Balaguru et al., 2018 source

In the paper

“The tropical Atlantic is the second largest source, after the tropical Pacific, of oceanic CO 2 to the atmosphere, releasing about 0.10 Pg C yr -1 in the 18 • S-18 • N region (Landschützer et al., 2014).”

What the sources say

• Supported

  Table 3 (section 8, page not specified) reports a 1998–2011 mean flux of 0.10 ± 0.06 Pg C yr⁻¹ from the Atlantic between 18°S and 18°N. Its listed fluxes place the tropical Pacific above the tropical Atlantic, supporting the stated ranking by estimated flux. (LLM, conf=0.94)

  cites Landschützer et al., 2014 source

In the paper

“Since the 1970s there has been an upward trend in the year-to-year variability of Amazon River discharge, following a period with no trend during 1904 through the 1960’s (Satyamurty et al., 2013;Barichivich et al., 2018).”

What the sources say

• Partly supported

  Section 3.2, paragraphs 13–14, reports that the annual range of Negro River water levels at Manaus increased after 1970, with no significant long-range trend from 1904 to the late 1960s. That supports the stated timing, but the measured trend is in the range between high and low water levels, not year-to-year variability of Amazon River discharge. (LLM, conf=0.87)

  cites Satyamurty et al., 2013 sourceExperimental — accuracy not yet measured
• Partly supported

  The Results section (page unavailable) reports that severe-flood frequency increased from around 1970, which supports a related increase in hydrological extremes. It does not establish an upward trend in year-to-year discharge variability or a trend-free period from 1904 through the 1960s. The Methods section says the study analyzed water levels rather than deriving discharge estimates. (LLM, conf=0.84)

  cites Barichivich et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“However, during 2005-2008 the Amazon was a net carbon source due to drought-stressed and dying trees, combined with increased occurrence of fires (Zeng et al., 2008;Yang et al., 2018).”

What the sources say

• Partly supported

  Section 3 (page not provided) reports that fires across the Amazon basin were more than twice as frequent in 2005 as the average of the preceding seven years, and says drought made forests more prone to burning. It does not establish that the Amazon was a net carbon source, attribute carbon emissions to stressed or dying trees, or document those conditions throughout 2005–2008. (LLM, conf=0.88)

  cites Zeng et al., 2008 sourceExperimental — accuracy not yet measured
• Partly supported

  The Results (Biomass and carbon changes) report post-2005 carbon losses, a shift to a carbon source in intact southern forests, and emissions from fires. But they do not show an increased occurrence of fires, and the Discussion cautions that the estimated drought-related loss is a decline in the forest carbon sink, not its absolute magnitude. The paper therefore does not establish that the entire Amazon was a net carbon source throughout 2005–2008 for the reasons stated. (LLM, conf=0.88)

  cites Yang et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“Summer equatorial variability associated with the AZM is also highly correlated with the next winter's ENSO (Polo et al., 2008;Rodríguez-Fonseca et al., 2009;Ding et al., 2012;Keenlyside et al., 2013;Martín-Rey et al., 2015).”

What the sources say

• Supported

  In “Equatorial Atlantic SST–Guinean Rainfall Mode: Air–Sea Interactions” (page not available), the paper reports that the maximum lagged correlation occurs when a warm equatorial Atlantic mode in summer precedes Pacific La Niña by 6–8 months, in the following winter. This supports the stated summer-to-next-winter association, specifically for the 1979–2002 period studied. (LLM, conf=0.90)

  cites Polo et al., 2008 source
• ?Not checked — no full text of the sourcecites Rodríguez-Fonseca et al., 2009 source
• ?Not checked — no full text of the sourcecites Ding et al., 2012 source

In the paper

“Significant trends in tropical Atlantic SST, surface salinity, upper-ocean heat content, winds, cloudiness, and rainfall have emerged in the past decade (Tokinaga and Xie, 2011;Durack et al., 2012;Servain et al., 2014).”

What the sources say

• ?Not checked — no full text of the sourcecites Tokinaga and Xie, 2011 source
• ?Could not verify

  The available indexed passages are UNT Digital Library navigation and bibliographic metadata, with no paper section or page containing the findings. Searches for tropical Atlantic trends and the listed variables found no passage addressing whether significant trends emerged in the past decade. The available copy therefore cannot verify the claim. (LLM, conf=0.74)

  cites Durack et al., 2012 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites Servain et al., 2014 source

In the paper

“A warm phase of the AZM shifts the intertropical convergence zone (ITCZ) anomalously to the south during June-August, increasing rainfall over the Gulf of Guinea (Figure 4A; Janicot et al., 1998;Okumura and Xie, 2004;Polo et al., 2008;Joly and Voldoire, 2010;Losada et al., 2010;Rodríguez-Fonseca et al., 2011, 2015).”

What the sources say

• ?Not checked — no full text of the sourcecites Janicot et al., 1998 source
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Okumura and Xie, 2004
• Partly supported

  The Introduction (page unavailable) links warm Atlantic conditions to wet years over the Gulf of Guinea and describes increased precipitation south of the ITCZ’s usual latitude. The SST–precipitation coupled modes section (page unavailable) also associates positive equatorial Atlantic SST anomalies with increased summer rainfall along the Gulf of Guinea coast. Our copy does not establish that the warm phase causes the ITCZ itself to shift south specifically during June–August; the paper analyzes June–September rainfall. (LLM, conf=0.85)

  cites Polo et al., 2008 sourceExperimental — accuracy not yet measured

In the paper

“Atlantic Multidecadal Variability (AMV; Kerr, 2000) modulates Sahel rainfall through its control of the Atlantic ITCZ (Knight et al., 2006;Zhang and Delworth, 2006;Mohino et al., 2011;Dieppois et al., 2015).”

What the sources say

• Supported

  Section 3 (Sahel Rainfall) says that warm AMO phases shift the Atlantic-sector ITCZ northward, increasing Sahel rainfall, while the opposite phase shifts it southward and reduces rainfall. Section 6 (Discussion and Conclusions) reiterates that reduced Sahel rainfall in negative AMO phases is linked to southward shifts of the mean ITCZ. (LLM, conf=0.94)

  cites Knight et al., 2006 source
• ?Not checked — no full text of the sourcecites Zhang and Delworth, 2006 source
• ?Not checked — no full text of the sourcecites Mohino et al., 2011 source

In the paper

“There is robust forcing of the tropical Atlantic from the tropical Pacific on interannual and longer timescales (Enfield and Mayer, 1997;Chiang et al., 2002;Villamayor and Mohino, 2015).”

What the sources say

• ?Not checked — no full text of the sourcecites Enfield and Mayer, 1997 source
• ?Not checked — no full text of the sourcecites Chiang et al., 2002 source
• Partly supported

  The Results report tropical Atlantic warming associated with the Pacific IPO in observations and simulations, which supports a link on decadal timescales. They also say the response outside the Pacific is less consistent across models; the paper does not establish robust Pacific forcing of the tropical Atlantic on interannual timescales. The robust finding concerns the IPO’s effect on Sahel rainfall. (LLM, conf=0.86)

  cites Villamayor and Mohino, 2015 sourceExperimental — accuracy not yet measured

In the paper

“This is especially true in the northwestern tropical Atlantic, where the Amazon-Orinoco plume increases salinity stratification, limiting hurricane-induced SST cooling (Figure 5; Balaguru et al., 2012;Grodsky et al., 2012b;Domingues et al., 2015).”

What the sources say

• Partly supported

  The Analysis reports that Hurricane Omar encountered barrier layers in the Caribbean and that SST cooling was substantially reduced there. The paper also explains that freshwater input can create salinity-related barrier layers, but our copy does not attribute the observed stratification to the Amazon–Orinoco plume or establish the claim specifically for the northwestern tropical Atlantic. The plume appears in a References entry, not in the paper’s account of this mechanism. (LLM, conf=0.85)

  cites Balaguru et al., 2012 sourceExperimental — accuracy not yet measured
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Grodsky et al., 2012b
• Supported

  The discussion reports that salinity-induced barrier layers linked to the Amazon–Orinoco plume can reduce hurricane-driven upper-ocean cooling. The Introduction likewise says near-surface salinity stratification can reduce storm-induced SST cooling. Page numbers are not supplied in our copy. (LLM, conf=0.92)

  cites Domingues et al., 2015 source

In the paper

“Uncertainties in near-surface air temperature and humidity are the leading sources of uncertainties for satellite-derived products (Prytherch et al., 2015).”

What the sources say

• Partly supported

  The Introduction (page not available in our copy) says variation in near-surface humidity fields is the largest source of uncertainty in global marine latent heat flux products. It does not make the same claim about air temperature or satellite-derived products generally. (LLM, conf=0.87)

  cites Prytherch et al., 2015 sourceExperimental — accuracy not yet measured

In the paper

“Oxygen can drop to zero in these eddies (Karstensen et al., 2015), substantially lower than the average value of 40 µmol kg -1 .”

What the sources say

• Partly supported

  The Abstract reports oxygen below 2 µmol kg⁻¹, lowest at eddy centres, and §3.1 describes the measured level as close to the threshold for anoxia—not zero. The Abstract and §3.1 also describe about 40 µmol kg⁻¹ as the region’s usual lower limit, rather than its average. (LLM, conf=0.88)

  cites Karstensen et al., 2015 sourceExperimental — accuracy not yet measured

In the paper

“Interannual variability in the equatorial and eastern boundary circulation due to equatorial and coastally trapped waves define the propagation characteristics of warm and cold anomalies of the AZM and Benguela Niño (Lübbecke et al., 2010).”

What the sources say

• Partly supported

  Section 3.3.2 (paragraphs 27 and 30) links interannual SST variability and the timing of warm and cold events to equatorial and coastal Kelvin-wave signals. But the Summary and Discussion (paragraphs 41 and 43) also attributes the different timing of Benguela and equatorial anomalies to thermocline depth and seasonal phase-locking; it does not establish that wave-driven circulation variability alone defines their propagation characteristics. Page numbers are unavailable in our copy. (LLM, conf=0.82)

  cites Lübbecke et al., 2010 sourceExperimental — accuracy not yet measured

In the paper

“Observational and modeling studies of the equatorial mixed layer heat balance have demonstrated the importance of vertical turbulent mixing for generating seasonal cooling of SST in the equatorial Atlantic (Foltz et al., 2003;Peter et al., 2006).”

What the sources say

• ?Not checked — no full text of the sourcecites Foltz et al., 2003 source
• Supported

  The Abstract reports seasonal equatorial mixed-layer cooling by vertical processes, strongest in June–August. Section 2.2 identifies vertical diffusion at the base of the mixed layer as the dominant contributor to that subsurface cooling, supporting the claim as attributed to this modeling study. (LLM, conf=0.89)

  cites Peter et al., 2006 source

In the paper

“In addition to vertical mixing and lateral eddy fluxes (Fischer et al., 2013;Hahn et al., 2014), latitudinally alternating zonal jets play a dominant role in the ventilation of the Atlantic OMZs (Brandt et al., 2010(Brandt et al., , 2012)).”

What the sources say

• Supported

  Fischer et al. is cited for vertical mixing and lateral eddy fluxes, not for the zonal-jet claim, which has separate citations. The paper’s Abstract states that diapycnal mixing supplies oxygen to the tropical North Atlantic OMZ and that this oxygen originates from lateral advective and eddy fluxes in the overlying layer. (LLM, conf=0.93)

  cites Fischer et al., 2013 source
• ?Not checked — no full text of the sourcecites Hahn et al., 2014 source
• ?Not checked — no full text of the sourcecites Brandt et al., 2010 source

In the paper

“The estimation contains uncertainty, which hampers our ability to accurately quantify air-sea thermodynamic interactions and heat budgets in the tropical Atlantic (Frankignoul and Kestenare, 2005;Pinker et al., 2014;Bentamy et al., 2017).”

What the sources say

• Partly supported

  Section 2, “The data” (page unavailable), describes noisy observations, model biases in surface heat fluxes, and discrepancies between datasets. Section 6, “Summary and conclusions” (page unavailable), cautions that model biases and inadequate algorithms may affect the results. These passages support uncertainty in flux-based estimates, but the paper does not specifically say that this hampers accurate quantification of tropical Atlantic heat budgets. (LLM, conf=0.84)

  cites Frankignoul and Kestenare, 2005 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites Pinker et al., 2014 source
• Partly supported

  The Introduction (page unavailable) says surface-flux products have biases and uncertainties and links flux accuracy to air–sea interaction studies and heat-budget closure. The Statistical Results (page unavailable) report discrepancies in tropical regions, but the passages do not establish the specific effect on quantifying heat budgets in the tropical Atlantic. (LLM, conf=0.82)

  cites Bentamy et al., 2017 sourceExperimental — accuracy not yet measured

In the paper

“For reanalysis fluxes, there are major uncertainties in tropical shortwave and longwave radiation associated with the long-standing problems of parameterizing tropical convective clouds and low-altitude stratocumulus clouds in reanalysis models (Trolliet et al., 2018).”

What the sources say

• Partly supported

  Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites Trolliet et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“Nevertheless, about 30% of the oxygen consumed in the OMZs of the eastern tropical Atlantic is replenished by interior ocean mixing processes sustained through internal wave-wave interaction (Brandt et al., 2015).”

What the sources say

• Partly supported

  The Abstract and §9 (Summary and discussion; page not provided) say vertical mixing supplies about 20% of the oxygen needed to balance consumption in the deep eastern tropical North Atlantic OMZ, reaching about 30% only locally. The claim generalizes that local figure to the region’s OMZs. The paper does not identify internal wave–wave interaction as the process sustaining that interior mixing; §6.3 instead discusses internal waves enhanced by tide–topography interaction at the continental margin. (LLM, conf=0.90)

  cites Brandt et al., 2015 sourceExperimental — accuracy not yet measured

In the paper

“On intraseasonal timescales, variability in the equatorial Atlantic is dominated by TIWs in the western and central part and by wind-driven waves in the east (Athie and Marin, 2008).”

What the sources say

• Supported

  The Summary and Conclusion (§6, paragraphs 52 and 57; page unavailable) identifies two dominant intraseasonal surface signals: TIWs west of 10°W and a 10–20-day signal east of 10°W in the Gulf of Guinea. It concludes that eastern signal is locally forced by meridional wind-stress variability, supporting the citing sentence’s regional distinction. (LLM, conf=0.94)

  cites Athie and Marin, 2008 source

In the paper

“Direct measurements of the surface heat flux have also proven valuable for diagnosing air-sea coupling in the southwestern tropical Atlantic near the Brazilian coast (Chaves and Nobre, 2004;De Almeida et al., 2007).”

What the sources say

• Partly supported

  The Methodology (§2, ¶9) says the study used model-generated and parameterized surface heat fluxes; the AGCM Experiments (§3.1, ¶11) use those heat budgets to examine ocean–atmosphere interaction in the western South Atlantic. This supports the value of heat-flux analysis, but not the claim that direct measurements proved valuable near the Brazilian coast. (LLM, conf=0.88)

  cites Chaves and Nobre, 2004 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites De Almeida et al., 2007 source

In the paper

“Moreover, there is evidence that mesoscale ocean dynamics significantly affect the tropical Atlantic Ocean and overlying atmospheric variability across a large range of time scales from daily to interannual and interdecadal (Seo et al., 2007;Chelton and Xie, 2010).”

What the sources say

• Partly supported

  The Abstract and §4 (Summary and discussion; page numbers unavailable) support an effect of tropical Atlantic instability waves on ocean currents, wind stress and atmospheric variability at short time scales. Section 4 describes longer-term effects as possible and says they require much longer simulations; it does not establish significant effects across interannual and interdecadal time scales. (LLM, conf=0.88)

  cites Seo et al., 2007 sourceExperimental — accuracy not yet measured
• Partly supported

  The paper’s opening section (p. 52) describes mesoscale sea-surface-temperature effects on winds and feedback on ocean temperature, and its Summary and Conclusions includes Atlantic tropical-instability-wave regions. It does not establish the claimed daily-to-interannual-and-interdecadal range for tropical Atlantic oceanic and atmospheric variability; the Introduction instead describes wind responses most clearly seen over weeks and persisting for a month or longer. (LLM, conf=0.84)

  cites Chelton and Xie, 2010 sourceExperimental — accuracy not yet measured

In the paper

“Hurricane-permitting global climate model simulations are becoming increasingly feasible (Patricola et al., 2014;Wehner et al., 2014;Walsh et al., 2015;Haarsma et al., 2016), but tend to overpredict hurricane activity if oceanic feedbacks are neglected (Zarzycki, 2016;Li and Sriver, 2018).”

What the sources say

• ?Not checked — no full text of the sourcecites Zarzycki, 2016 source
• Supported

  The Abstract reports that the uncoupled atmosphere-only simulation produced more storms and higher overall storm intensity than the coupled simulations. Section 4 (TC Distribution, Number, and Seasonality) also reports more intense storms in every basin than in the coupled models and observations, supporting the claim that omitting ocean feedbacks can overpredict hurricane activity. Page numbers are unavailable in our copy. (LLM, conf=0.88)

  cites Li and Sriver, 2018 source

In the paper

“Poor representation of the AZM in many models appears related to the under-representation of the thermocline feedback associated with an overly deep mixed layer and too weak upwelling in the eastern Atlantic (Ding et al., 2015a,b;Deppenmeier et al., 2016;Dippe et al., 2018;Jouanno et al., 2017).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Ding et al., 2015a,b
• Partly supported

  Section 4.3 (page unavailable) reports that models generally underestimate the influence of subsurface heat-content anomalies on eastern Atlantic SST, and the Conclusion links poor representation of that feedback to erroneous vertical oceanic stratification. The paper does not establish an overly deep mixed layer or too-weak eastern Atlantic upwelling as the causes; the Conclusion says the subsurface errors could arise from ocean mixing and/or atmospheric forcing. (LLM, conf=0.88)

  cites Deppenmeier et al., 2016 sourceExperimental — accuracy not yet measured
• Partly supported

  The Introduction says biased simulations have a deeper thermocline and strongly reduced upwelling in the cold-tongue region, making the Atlantic Niño difficult to reproduce. Section 6 links the model bias to impaired feedback, but identifies the KCM’s main problem as the SST–wind relationship. The paper does not attribute that impairment to an overly deep mixed layer; thermocline depth is not mixed-layer depth. (LLM, conf=0.88)

  cites Dippe et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“Many data products poorly represent the atmospheric and oceanic circulations in the region (Large and Yeager, 2008;Patricola and Chang, 2017;Tchipalanga et al., 2018), underscoring the need for updated products at higher resolution.”

What the sources say

• ?Not checked — no full text of the sourcecites Large and Yeager, 2008 source
• ?Not checked — no full text of the sourcecites Patricola and Chang, 2017 source
• Partly supported

  The Summary and Discussion (page not available) reports substantial biases in simulated ocean-current velocity structures and upwelling strength, as well as large salinity biases in several ocean reanalysis products. It does not establish that data products also poorly represent atmospheric circulation in the Benguela region. (LLM, conf=0.85)

  cites Tchipalanga et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“The large-scale meteorology that affects low clouds in this region is influenced by strong coupling between the Atlantic basin and neighboring continents (Adebiyi et al., 2015;Adebiyi and Zuidema, 2016).”

What the sources say

• Supported

  The Abstract describes linked changes in a southern African anticyclone and the South Atlantic anticyclone that transport continental air offshore and alter stability over the stratocumulus deck. Section 6, “Spatial patterns as a function of aerosol loading” (page not available), likewise links Atlantic circulation to temperature and moisture advection from the continent. Together, these support the claim that land–ocean meteorological interactions affect the region’s low clouds. (LLM, conf=0.88)

  cites Adebiyi et al., 2015 source
• ?Not checked — no full text of the sourcecites Adebiyi and Zuidema, 2016 source

In the paper

“Based on reliable SST observations, we know that the Angola current and the associated ABF are placed too far south in GCMs by about 10 • of latitude (Xu et al., 2014a;Koseki et al., 2018).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Xu et al., 2014a
• Partly supported

  Section 2.2 reports that the observed Angola and Benguela currents meet near 15°S, while NorESM places the front at 24°S—roughly 9° too far south—and simulates a stronger southward Angola Current. This supports the approximate displacement for NorESM, but not the claim that GCMs generally displace the current and front by about 10°. (LLM, conf=0.87)

  cites Koseki et al., 2018 sourceExperimental — accuracy not yet measured

In the paper

“This assumption does not account for the intense microbial activity, which may foster OM degradation or remineralisation (Bretagnon et al., 2018).”

What the sources say

• Supported

  The Introduction contrasts the expectation that low oxygen preserves organic matter with the possibility that intense microbial activity induces efficient remineralisation. The Abstract likewise says that OMZs would be expected to foster preservation, but their microbial activity should enhance degradation. (LLM, conf=0.94)

  cites Bretagnon et al., 2018 source

In the paper

“From an uncoupled ocean perspective, there is also a strong impact from water mass observations over the full water column, which have been shown to improve reanalysis fields locally by several units in temperature and salinity (Oke et al., 2015;Turpin et al., 2016;Gasparin et al., 2018).”

What the sources say

• ?Not checked — no full text of the sourcecites Oke et al., 2015 source
• Partly supported

  The Conclusion reports that assimilating Argo observations improves temperature and salinity analyses and reduces observation–forecast differences; §3.1 finds locally substantial effects. But the study covers profiles from the surface to 2000 m, not the full water column, and its reported differences are around 1 °C and tenths of a psu, not several units of both temperature and salinity. (LLM, conf=0.88)

  cites Turpin et al., 2016 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites Gasparin et al., 2018 source

In the paper

“For instance, the impact of surface pressure is one order of magnitude larger than the impact of wind measured on the same buoys.”

What the sources say

• ?Could not verify

  The Data and methodology passage (p. 2) identifies PIRATA buoys with barometers and buoys for which only wind observations were assimilated. The available Results passage discusses forecast impact but stops before any pressure-versus-wind comparison. Searches for the claimed order-of-magnitude difference and pressure-to-wind impact ratio found no passage that establishes it. (LLM, conf=0.70)

  cites Poli (2018) sourceExperimental — accuracy not yet measured

In the paper

“The assimilation of PIRATA data was also found to improve significantly the intraseasonal variability of upper-ocean temperature (Belyaev et al., 2001), while the impact on seasonal to longer-range prediction systems needs to be investigated and quantified in more detail.”

What the sources say

• Supported

  The numerical experiments and results (Section 4; page unavailable) compare PIRATA temperature assimilation with a model run without assimilation. They report significantly smaller temperature-error variance after assimilation over the course of a month, including for temperatures averaged over the upper 500 m, supporting the claimed improvement in intraseasonal upper-ocean temperature variability. (LLM, conf=0.90)

  cites Belyaev et al., 2001 source

In the paper

“From a NWP perspective, Poli (2018) analyzed the impact of observations on the ECMWF operational data assimilation scheme and showed that surface pressure measurements from PIRATA buoys have a higher positive impact per datum than many other types of observations (satellite, upper-air, land surface, or sea surface other than buoys).”

What the sources say

• Partly supported

  The Introduction (pp. 1–2) says Poli analyzed PIRATA observations in ECMWF’s operational system. The Results say sea-surface observations had a larger share of forecast improvement than their share of observation counts, but the available passage does not establish that PIRATA surface-pressure measurements had a higher positive impact per datum than the listed observation types. (LLM, conf=0.76)

  cites Poli (2018) sourceExperimental — accuracy not yet measured

In the paper

“Interannual variability of air-sea CO 2 fluxes is closely linked to climate variability (Lefèvre et al., 2013;Ibánhez et al., 2017).”

What the sources say

• Supported

  The Conclusions (§7, paragraph 49) explicitly link climate variability with CO₂ exchange across the air–sea interface. They identify the 2010 El Niño teleconnection and associated rainfall reduction as drivers of increased tropical Atlantic CO₂ flux, supporting the cited background statement about interannual variability. (LLM, conf=0.88)

  cites Lefèvre et al., 2013 source
• Supported

  In Results and Discussion, under “Basin-scale anomalous sea-air CO2 exchange in 2010” (page not available), the paper links climate modes to SST anomalies and says these strongly affect sea-air CO2 exchange in the tropical and subtropical North Atlantic. The discussion of physical contributors also identifies SST and wind anomalies as the main contributors to the 2010 CO2 flux anomalies. (LLM, conf=0.89)

  cites Ibánhez et al., 2017 source

In the paper

“One is that the turbulent surface fluxes often overcompensate for the enhanced shortwave warming (de Szoeke et al., 2010).”

What the sources say

• Partly supported

  Section 6 reports excessive turbulent-flux cooling in the models, balanced against excess radiative warming and insufficient oceanic cooling. The Summary says excess evaporation is about 40 W m⁻² versus about 20 W m⁻² of net excess radiation after longwave compensation. This supports overcompensation of net radiative warming, but does not establish that turbulent fluxes often exceed the enhanced shortwave warming alone. (LLM, conf=0.84)

  cites de Szoeke et al., 2010 sourceExperimental — accuracy not yet measured

In the paper

“Based on oxygen observations from repeat ship sections in the OMZ of the eastern tropical North Atlantic for the recent decade (2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015), Hahn et al. (2017) suggested the existence of strong oxygen variations over this decade that are superimposed on the multi-decadal deoxygenation pattern (Stramma et al., 2009;Brandt et al., 2015;Santos et al., 2”

What the sources say

• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites Hahn et al., 2017 source
• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites Stramma et al., 2009 source
• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites Brandt et al., 2015 source

In the paper

“In the eastern tropical Atlantic, estimates of the biological pump and its dependence on oxygen availability are complicated by the presence of mesoscale eddies, which contain shallow (40-100 m) suboxic environments (Karstensen et al., 2015).”

What the sources say

• Partly supported

  The Introduction reports extremely low oxygen in mesoscale eddies in the eastern tropical North Atlantic, and §3.1 places one low-oxygen eddy core around 70 m depth. Section 3.4 links sinking particles to oxygen consumption, but does not establish that eddies complicate estimates of the biological pump or its dependence on oxygen availability; it says the available data cannot be used to estimate productivity. Page numbers were not provided in our copy. (LLM, conf=0.85)

  cites Karstensen et al., 2015 sourceExperimental — accuracy not yet measured

In the paper

“In models, interannual variations of temperature, nitrate, and oxygen concentrations along the southwestern coast of Africa are primarily controlled by oceanic teleconnections associated with equatorial wave variability and along-shore water mass transport (Mohrholz et al., 2008;Bachèlery, 2016;Bachèlery et al., 2016a,b;Koungue et al., 2017).”

What the sources say

• ?Not checked — no full text of the sourcecites Mohrholz et al., 2008 source
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bachèlery, 2016
• Partly supported

  The Introduction reports modeling results in which equatorial remote forcing explains more than 80% of interannual coastal sea-surface temperature, nitrate, and oxygen variability. The Summary, Discussion, and Conclusions discusses advection of water masses but says its importance at interannual timescales is difficult to assess; it does not establish along-shore transport as a primary control. (LLM, conf=0.86)

  cites Koungue et al., 2017 sourceExperimental — accuracy not yet measured

In the paper

“The number of measurements of fCO 2 increased from about 0.3 million per year during 1995-2000 to 1.1 million per year during 2005-2012 (Bakker et al., 2016).”

What the sources say

• Supported

  Section 7.1 reports 0.2–0.4 million SOCAT fCO₂ values per year in 1995–2000 and 1.0–1.2 million per year in 2005–2012. The claim’s approximate figures are the midpoints of those ranges. (LLM, conf=0.94)

  cites Bakker et al., 2016 source

In the paper

“An array consisting of four velocity moorings has been installed at the Brazilian continental slope along 11 • S from 2000 to 2004 and since 2013, measuring the shallow and DWBC (Schott et al., 2005;Hummels et al., 2015).”

What the sources say

• Partly supported

  The moored-array observations section reports measurements near 11°S from 2000 to 2004, covering shallow flow and the deep western boundary current. It says the array initially had five moorings; four were deployed from 2002 to 2004. This 2005 paper does not document the installation since 2013 mentioned in the jointly cited sentence. (LLM, conf=0.90)

  cites Schott et al., 2005 sourceExperimental — accuracy not yet measured
• Supported

  The Introduction says a four-mooring array equipped with current meters was deployed off Brazil at 11°S in July 2013 and compares it with moored observations from 2000–2004. The Abstract says a similar array was installed there during the earlier period, and section 3 reports moored transport time series for both the shallow North Brazil Undercurrent and the DWBC. (LLM, conf=0.93)

  cites Hummels et al., 2015 source

In the paper

“The spread in net surface heat flux (Q net ) mean values is large across the entire tropical basin (standard deviation > 20 W m -2 based on 12 different products; Figure 7).”

In the paper

“In the tropical Atlantic away from the equatorial cold tongue, the standard deviation of Q net is as large as the ensemble-mean Q net .”

In the paper

“For example, the RT-ORA-IP exercise illustrates that in spite of a reasonably well captured thermocline structure along the equatorial band, heat content anomalies close to the mouth of the Amazon show strong disagreement due to large differences in river discharge applied in the different reanalyses and the associated resultant differences in local ocean circulation.”

In the paper

“This project has been expanded to cover the tropical Atlantic and shows that overall, in the equatorial Atlantic the agreement between reanalyses is often reasonable.”

In the paper

“However, locally the spread between estimates can reach 2 • C in the thermocline 7 .”

In the paper

“Furthermore, there are large disparities between offequatorial winds measured directly by PIRATA and estimated by satellites and model-based reanalyses (Bentamy and Fillon, 2012), emphasizing the importance of maintaining the long records from all PIRATA moorings.”

What the sources say

• ?Not checked — no full text of the sourcecites Bentamy and Fillon, 2012 source

In the paper

“1998, the array in the tropical Atlantic has averaged 92 drifters, and since 2005 drifter measurements have been approximately hourly.”

In the paper

“Through its impacts on soil moisture, vegetation, and albedo, the rainfall received during a given year affects the likelihood of drought the following year, acting to enhance decadal-multidecadal variations of Sahel rainfall (Zeng et al., 1999).”

What the sources say

• ?Not checked — no full text of the sourcecites Zeng et al., 1999 source

In the paper

“During 2011-2016, Northeast Brazil experienced its most severe and prolonged drought since 1981 (Brito et al., 2018).”

What the sources say

• ?Not checked — no full text of the sourcecites Brito et al., 2018 source

In the paper

“There have been marked changes in Atlantic land-falling TCs in the past several decades (Wang et al., 2011;Kossin, 2017).”

What the sources say

• ?Not checked — no full text of the sourcecites Wang et al., 2011 source
• ?Not checked — no full text of the sourcecites Kossin, 2017 source

In the paper

“There are indications that TC activity and intensification before landfall may be increasing in the Atlantic due to global warming (Emanuel, 2005(Emanuel, , 2017;;Webster et al., 2005;Elsner et al., 2008).”

What the sources say

• ?Not checked — no full text of the sourcecites Emanuel, 2005 source
• ?Not checked — no full text of the sourcecites Webster et al., 2005 source
• ?Not checked — no full text of the sourcecites Elsner et al., 2008 source

In the paper

“There is also significant external forcing of TAV from ENSO, the North Atlantic Oscillation, and the South Atlantic Anticyclone (Enfield and Mayer, 1997;Czaja et al., 2002;Chang et al., 2006;Illig and Dewitte, 2006;Lübbecke et al., 2010;Lübbecke and McPhaden, 2012).”

What the sources say

• ?Not checked — no full text of the sourcecites Enfield and Mayer, 1997 source
• ?Not checked — no full text of the sourcecites Czaja et al., 2002 source
• ?Not checked — no full text of the sourcecites Chang et al., 2006 source

In the paper

“TAV involves coupled ocean-atmosphere processes and their interactions, most notably, fluctuations of the trade winds, SST, and rainfall (Figure 3; Xie and Carton, 2004).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Xie and Carton, 2004

In the paper

“Their threats to marine life are primarily mechanical, due to ingestion of plastics and entanglement (Derraik, 2002).”

What the sources say

• ?Not checked — no full text of the sourcecites Derraik, 2002 source

In the paper

“The shorter period of EDJs in the Atlantic compared to the Pacific, combined with the strong and shallow EUC in the eastern equatorial Atlantic, enables EDJs to influence interannual climate variability in the Atlantic (Brandt et al., 2011b).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Brandt et al., 2011b

In the paper

“For satellite fluxes, major uncertainties are related to turbulent bulk flux parameterization schemes and also satellite retrieval algorithms.”

In the paper

“NBC rings interact with the Amazon and Orinoco river plumes, modifying barrier layers and thus affecting TC intensification.”

In the paper

“Turbulent mixing in the upper thermocline above the upper continental slopes and shelves of the eastern boundary upwelling regions is a dominant process bringing colder, nutrient-rich water from the deeper ocean to the surface mixed layer.”

What the sources say

• ?Not checked — no full text of the sourcecites Schafstall et al., 2010 source

In the paper

“All Q net products have problems achieving a balanced energy budget at the ocean surface, with an overestimation of the downward heat input to the ocean ranging from 5 to 20 W m -2 (Yu, 2019).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Yu, 2019

In the paper

“Predicting tropical Atlantic climate is challenging, and the difficulty is exacerbated by persistent coupled climate model biases.”

In the paper

“At the equator, EDJs contribute to the ventilation of the eastern basin (Brandt et al., 2012).”

What the sources say

• ?Not checked — no full text of the sourcecites Brandt et al., 2012 source

In the paper

“Mixing is enhanced due to tide-topography interaction that largely sustains the elevated productivity in the Atlantic's eastern boundary upwelling regions (Schafstall et al., 2010).”

What the sources say

• ?Not checked — no full text of the sourcecites Schafstall et al., 2010 source

In the paper

“The strength of the EUC undergoes a strong seasonal cycle in response to wind forcing (Johns et al., 2014;Brandt et al., 2016).”

What the sources say

• ?Not checked — no full text of the sourcecites Johns et al., 2014 source
• ?Not checked — no full text of the sourcecites Brandt et al., 2016 source

In the paper

“Some uncertainty remains in the actual near-coastal wind-stress curl, owing to the lack of reliable satellite data and atmospheric observations near land (Desbiolles et al., 2016).”

What the sources say

• ?Not checked — no full text of the sourcecites Desbiolles et al., 2016 source

In the paper

“Predicting the AZM is particularly challenging, with dynamical forecasts often matched or even outperformed by persistence forecasts (Stockdale et al., 2006;Richter et al., 2017).”

What the sources say

• ?Not checked — no full text of the sourcecites Stockdale et al., 2006 source
• ?Not checked — no full text of the sourcecites Richter et al., 2017 source

In the paper

“As a consequence, even the theory underpinning the existence of the Angola current is not completely settled (Junker et al., 2015).”

What the sources say

• ?Not checked — no full text of the sourcecites Junker et al., 2015 source

In the paper

“One contribution to the insufficient cold tongue development in models is the equatorial westerly wind bias in March-May (Figure 9), which deepens the thermocline and inhibits cooling during the subsequent June-August upwelling season (Richter and Xie, 2008;Richter et al., 2012).”

What the sources say

• ?Not checked — no full text of the sourcecites Richter and Xie, 2008 source
• ?Not checked — no full text of the sourcecites Richter et al., 2012 source

In the paper

“The tropical Atlantic biases weaken the Atlantic's global impact in models (McGregor et al., 2018).”

What the sources say

• ?Not checked — no full text of the sourcecites McGregor et al., 2018 source

In the paper

“However, the cool SST bias in the northern tropical Atlantic, common to coupled models (Richter, 2015;Zuidema et al., 2016b), can cause a 65% underrepresentation of Atlantic hurricane activity (Hsu et al., 2019).”

What the sources say

• ?Not checked — no full text of the sourcecites Hsu et al., 2019 source

In the paper

“One common attribution of the warm SST biases in the Southeast Atlantic is an under-representation of the marine stratocumulus deck, which then allows too much sunlight to reach the ocean surface.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Klein and Hartmann, 1993
• ?Not checked — no full text of the sourcecites Huang et al., 2007 source
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Hu et al., 2008

In the paper

“Conversely, ecosystem models have rarely included such quantitative approaches.”

In the paper

“For instance, Busalacchi (1996) showed that the direct assimilation of sea level and thermocline depth observations improves the upperocean structure in the equatorial Atlantic.”

What the sources say

• ?Not checked — no full text of the sourcecites Busalacchi (1996) source

In the paper

“Ocean warming and the related solubility effect are responsible for about half of the multi-decadal oxygen decline in the upper 1200 m (Schmidtko et al., 2017).”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidtko et al., 2017 source

In the paper

“The cause of parameterization biases is often model specific (Medeiros et al., 2012), and ongoing observations of the boundary layer thermodynamic structure and its cloud, precipitation, and aerosol vertical structure, including the diurnal cycle, are needed for continued model improvement.”

What the sources say

• ?Not checked — no full text of the sourcecites Medeiros et al., 2012 source

In the paper

“These difficulties often result from extensions of geostrophic balance using empirical approximations (e.g., Weaver et al., 2005).”

What the sources say

• ?Not checked — no full text of the sourcecites Weaver et al., 2005 source

In the paper

“While data assimilation techniques and OSSEs are less mature for biogeochemical observations, dedicated experiments suggest that assimilation of biogeochemical Argo data will complement satellite surface color data by improving model estimates of oxygen, nutrients, carbon, and chlorophyll throughout the water column.”

In the paper

“However, satellite scatterometer, altimeter, and synthetic aperture radar data are providing valuable assimilation constraints for wind and sea-state forecasts by NWP systems (Isaksen and Janssen, 2004;Dragani et al., 2015).”

What the sources say

• ?Not checked — no full text of the sourcecites Isaksen and Janssen, 2004 source
• ?Not checked — no full text of the sourcecites Dragani et al., 2015 source

In the paper

“Uncertainties in ocean reanalyses are largest in these regions due to sparse observations, large model errors and uncertainties in river run-off as well as air-sea heat, moisture, and momentum fluxes.”

In the paper

“Most data assimilation systems also suffer from overly simplistic balance (crosscovariance) formulations close to the equator that may jeopardize the assimilation of local observations.”

In the paper

“Such observational datasets remain sparse for the Southeast Atlantic.”

In the paper

“The other is that even for AMIP simulations in which the SST is specified, the cloud radiative effect on the surface is still underestimated, with bias reductions of only ∼25% (Zuidema et al., 2016a).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Zuidema et al., 2016a

In the paper

“However, no long-term measurements of horizontal velocity, vertical shear, and turbulent mixing exist in the tropical Atlantic outside the equatorial band (Figure 6).”

In the paper

“For winds less than about 3 m s -1 or greater than 20 m s -1 , the uncertainties are generally larger.”

In the paper

“Satellite observations have greatly improved the coverage, resolution, and accuracy of surface buoyancy and momentum flux estimates (Yu, 2018).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Yu, 2018

In the paper

“Despite significant progress, these variables remain the leading source of error in satellite-based surface heat flux products.”

In the paper

“The radiation budget at the ocean's surface is not remotely sensed.Instead it is estimated from radiative transfer calculations that use satellite-derived TOA irradiance, cloud and aerosol properties, and the atmospheric state from either satellites or reanalysis.”

In the paper

“There is a high degree of integration among the various sustained observing components so that weaknesses of some are compensated by the strengths of others.”

In the paper

“The vertical spacing of conductivity sensors on most moorings is much too coarse for accurate resolution of the mixed layer and salinity stratification required for heat and salinity budget analyses.”

In the paper

“Because of the cloud effect, it takes one or two weeks to obtain a complete global SST field from AVHRR even though the satellite orbits the Earth 14 times each day and has a 2399-km-wide swath.”

In the paper

“There is therefore a high degree of complementarity between satellite and in situ measurements.”

In the paper

“However, PIRATA moorings do not sample the warm pool region to the west, where there are strong mesoscale eddies (Figure 8), seasonal variations of upperocean salinity stratification that affect SST and TCs, and strong multidecadal variations of upper-ocean heat content and SST (Figure 11).”

In the paper

“Oxygen and f CO 2 are not monitored by many elements of the tropical Atlantic observing system.”

In the paper

“There are very few measurements of surface wave height and spectra in the tropical Atlantic, which are needed to improve forecasts and to advance understanding of wave-induced upper-ocean mixing.”

In the paper

“A current lack of monitoring of biological variables also makes it challenging to determine how ecosystems will cope with changing physical and biogeochemical conditions.”

In the paper

“It is difficult to close the heat and salinity budgets at many PIRATA mooring locations because at present less than half of the moorings have direct measurements of longwave radiation and ocean currents.”

In the paper

“Thus, for PIRATA the ocean biogeochemistry and ecosystem observation capabilities have not yet been fully explored.”

In the paper

“In general, biogeochemical quantities are severely undersampled compared to many physical parameters, especially in the tropical South Atlantic (Figure 12).”

In the paper

“Therefore, the success of the tropical Atlantic observing system depends in part on the maintenance and evolution of those observing systems.”