Reconstruction of the marine carbonate system at the Western Tropical Atlantic: trends and variabilities from 20 years of the PIRATA program

The Western Tropical Atlantic Ocean (WTAO) is crucial for understanding CO2 dynamics due to inputs from major rivers (Amazon and Orinoco), substantial rainfall from the Intertropical Convergence Zone (ITCZ), and CO2-rich waters from equatorial upwelling. This study, spanning 1998 to 2018, utilized sea surface temperature (SST) and sea surface salinity (SSS) data from the PIRATA buoy at 8°N 38°W to reconstruct the surface marine carbonate system. Empirical models derived total alkalinity (TA) and dissolved inorganic carbon (DIC) from SSS, with subsequent estimation of pH and fCO2 from TA, DIC, SSS, and SST data. Linear trend analysis showed statistically significant temporal trends: DIC and fCO2 increased at a rate of 0.7 µmol kg-1 year-1 and 1.539 µatm year-1, respectively, and pH decreased at a rate of -0.001 pH units year-1, although DIC did not show any trend after data was de-seasoned. Rainfall analysis revealed distinct dry (July to December) and wet (January to June) seasons, aligning with lower and higher freshwater influence on the ocean surface, respectively. TA, DIC, and pH correlated positively with SSS, exhibiting higher values during the dry season and lower values during the wet season. Conversely, fCO2 correlated positively with SST, showcasing higher values during the wet season and lower values during the dry season. This emphasizes the influential roles of SSS and SST variability in CO2 solubility within the region. Finally, we have analysed the difference between TA and DIC (TA-DIC) as an indicator for ocean acidification and found a decreasing trend of -0.93 ± 0.02 μmol kg-1 year-1, reinforcing the reduction in the surface ocean buffering capacity in this area. All trends found for the region agree with data from other stations in the tropical and subtropical Atlantic Ocean. In conclusion, the use of empirical models proposed in this study has proven to help filling the gaps in marine carbonate system data in the Western Tropical Atlantic

The Ocean and Cryosphere in a Changing Climate in Latin America: Knowledge Gaps and the Urgency to Translate Science Into Action

Climate Change hazards to social-ecological systems are well-documented and the time to act is now. The IPCC-SROCC used the best available scientific knowledge to identify paths for effective adaptation and mitigation of climate change impacts on the ocean and cryosphere. Despite all the evidence highlighted by SROCC and the key role of the ocean and cryosphere for climate change at all levels, Latin America (LA) faces challenges to take effective action mostly due to socio-economic vulnerability, political instability and overall technical capacities. Countries have adopted diverse actions as the information needed by policy makers has been made available, not necessarily in accessible and inclusive ways. Regional imbalance in economic development, technological level, capacity development, societal involvement, and governmental oversight have contributed to skewed geographical and technological gaps of knowledge on key ecosystems and specific areas preventing effective climate actions/solutions. We analyze the Nationally Determined Contributions (NDCs) from the region as proxies to the incorporation of IPCC recommendations. The gaps and opportunities for the uptake of ocean and climate science to political decision making is discussed as five key aspects: (i) climate assessment information and regional policies, (ii) knowledge production, (iii) knowledge accessibility, (iv) knowledge impact to policy, and (v) long term monitoring for decision making. We advocate that the uptake of SROCC findings in LA policies can be enhanced by: (a) embracing local realities and incorporating local, traditional and indigenous knowledge; (b) empowering locals to convey local knowledge to global assessments and adapt findings to local realities; (c) enhancing regional research capabilities; and (d) securing long-term sustainable ocean observations. Local and regional participation in knowledge production and provision enhances communication pathways, climate literacy and engagement which are key for effective action to be reflected in governance. Currently, the lack of accessible and inclusive information at the local level hampers the overall understanding, integration and engagement of the society to mitigate climate effects, perpetuates regional heterogeneity and threatens the efforts to reverse the course of climate change in LA. Local researchers should be empowered, encouraged, rewarded and better included in global climate-ocean scientific assessments.Fil: Muelbert, Mônica M. C.. Universidade Federal de Sao Paulo; Brasil. Universidade Federal do Rio Grande; BrasilFil: Copertino, Margareth. Universidade Federal do Rio Grande; Brasil. Rede Brasileira de Pesquisas sobre Mudanças Climáticas Globais; BrasilFil: Cotrim da Cunha, Leticia. Rede Brasileira de Pesquisas sobre Mudanças Climáticas Globais; Brasil. Universidade do Estado de Rio do Janeiro; BrasilFil: Lewis, Mirtha Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Polejack, Andrei. World Maritime University; Suecia. Ministério de Ciência, Tecnologia e Inovações; BrasilFil: Peña Puch, Angelina del Carmen. Universidad Autónoma de Campeche; MéxicoFil: Rivera Arriaga, Evelia. Universidad Autónoma de Campeche; Méxic

Sea-air CO2 fluxes along the Brazilian continental margin

Measurements of the marine carbonate system on tropical and subtropical continental margins are poorlydistributed in space and time, with many uncertainties persisting regarding the role of carbon exchanges at theocean-atmosphere interface in these areas. To calculate sea-to-air CO2 fluxes in Marine Ecoregions along theBrazilian continental margin (4°N to 34°S), we used data from the Surface Ocean CO2 Atlas (SOCAT v2020),collected up to 400 km from the coast, at the surface (5 m), between 1991 and 2018, with the aim of investigatingthe role of ecoregions as potential sinks or sources of atmospheric CO2. The temperature and salinity of seawaterpresented variability in the north-south direction mainly because of the broad latitudinal range, reflecting typicalpatterns of tropical (T = 27.4°C ±1.49; S = 36.4 ±1.91) and subtropical waters (T = 22.8°C ±3.41; S = 35 ±2.91), inaddition to the greater or lesser influence of river inputs in each ecoregion. The pCO2 values in the surface watersvaried from 121.81 (Amazon) to 478.92 µatm (Eastern), differing significantly between ecoregions and showingan expected decadal increasing trend, both in the atmosphere and in the seawater. The calculated values of CO2fluxes showed non-homogeneous spatio-temporal variations, from -24.37 mmol m-2 d-1 (Rio Grande) to 9.87 mmolm- 2 d-1 (Southeastern). Throughout the analyzed time series, we observed that the Northeast, Amazon and Easternecoregions acted predominantly as sources of CO2 and the Southeastern ecoregions and, mainly, Rio Grande,acted predominantly as sinks of atmospheric CO

Organization & sustainability of PIRATA network Report

A detailed report on the renewed PIRATA network, and its potential sustainability over long-term. This deliverable has been established with the contribution of the PIRATA International Scientific Steering Group and PIRATA partners

Nonalcoholic steatohepatitis and hepatocellular carcinoma: Brazilian survey

OBJECTIVE: The majority of cases of hepatocellular carcinoma have been reported in individuals with cirrhosis due to chronic viral hepatitis and alcoholism, but recently, the prevalence has become increasingly related to nonalcoholic steatohepatitis around the world. The study aimed to evaluate the clinical and histophatological characteristics of hepatocellular carcinoma in Brazilians' patients with nonalcoholic steatohepatitis at the present time. METHODS: Members of the Brazilian Society of Hepatology were invited to complete a survey regarding patients with hepatocellular carcinoma related to nonalcoholic steatohepatitis. Patients with a history of alcohol intake (>;20 g/day) and other liver diseases were excluded. Hepatocellular carcinoma diagnosis was performed by liver biopsy or imaging methods according to the American Association for the Study of Liver Diseases’ 2011 guidelines. RESULTS: The survey included 110 patients with a diagnosis of hepatocellular carcinoma and nonalcoholic fatty liver disease from nine hepatology units in six Brazilian states (Bahia, Minas Gerais, Rio de Janeiro, São Paulo, Paraná and Rio Grande do Sul). The mean age was 67±11 years old, and 65.5% were male. Obesity was observed in 52.7% of the cases; diabetes, in 73.6%; dyslipidemia, in 41.0%; arterial hypertension, in 60%; and metabolic syndrome, in 57.2%. Steatohepatitis without fibrosis was observed in 3.8% of cases; steatohepatitis with fibrosis (grades 1-3), in 27%; and cirrhosis, in 61.5%. Histological diagnosis of hepatocellular carcinoma was performed in 47.2% of the patients, with hepatocellular carcinoma without cirrhosis accounting for 7.7%. In total, 58 patients with cirrhosis had their diagnosis by ultrasound confirmed by computed tomography or magnetic resonance imaging. Of these, 55% had 1 nodule; 17%, 2 nodules; and 28%, ≥3 nodules. CONCLUSIONS: Nonalcoholic steatohepatitis is a relevant risk factor associated with hepatocellular carcinoma in patients with and without cirrhosis in Brazil. In this survey, hepatocellular carcinoma was observed in elevated numbers of patients with steatohepatitis without cirrhosis

Report on demo mission and dissemination pathways of obtained data based on different observational platforms

This document describes the deployment of instrumentation in the Eastern tropical Atlantic area and shows the preliminary data acquired

PIRATA: A Sustained Observing System for Tropical Atlantic Climate Research and Forecasting

Prediction and Research Moored Array in the Tropical Atlantic (PIRATA) is a multinational program initiated in 1997 in the tropical Atlantic to improve our understanding and ability to predict ocean-atmosphere variability. PIRATA consists of a network of moored buoys providing meteorological and oceanographic data transmitted in real time to address fundamental scientific questions as well as societal needs. The network is maintained through dedicated yearly cruises, which allow for extensive complementary shipboard measurements and provide platforms for deployment of other components of the Tropical Atlantic Observing System. This paper describes network enhancements, scientific accomplishments and successes obtained from the last 10 years of observations, and additional results enabled by cooperation with other national and international programs. Capacity building activities and the role of PIRATA in a future Tropical Atlantic Observing System that is presently being optimized are also described