Concentrations and source assessment of black carbon across tropical Atlantic air and sediment

热带大西洋空气和沉积物中黑碳的浓度和来源评估PI：Lohmann（URI）; co-PI：Pockalny（URI）黑碳是在燃料不完全燃烧过程中形成的（例如，公共汽车和卡车排放的黑色烟雾）。黑碳在环境中不易降解，可以长距离运输，甚至到达海底。然而，黑碳在环境中的通量并不为人所知，特别是在海洋中。河流被认为是海洋黑碳的主要来源。然而，最近的研究结果表明，在海洋的某些区域，大气中黑碳的输送可能很重要。这项研究调查了生物质燃烧（例如，非洲的野火）是热带大西洋黑碳的来源。黑碳独特的分子和同位素特性将被用来识别研究区域大气、水和沉积物中的黑碳。沉积物、水柱和大气颗粒物将在为期3周的横跨热带大西洋的研究巡航中收集。将使用两种不同的方法来量化环境中的黑碳。这项研究对于我们理解碳循环是相关和及时的，碳循环是我们预测气候及其变化能力的关键组成部分。该项目支持一名研究生，并为参加SMILE计划（科学和数学研究性学习体验）的高中生提供机会。该项目由化学海洋学计划和刺激竞争性研究既定计划（EPSCoR）联合资助，将在非洲受生物质燃烧事件（野火）影响的热带大西洋地区的10个地点收集表层沉积物样本。将使用最先进的船舶设备确定沉积物取样的适当地点，以确保取芯作业取得成功。一旦收集，沉积物的黑碳和有机碳部分将被分离和测量。一系列同位素和分子标记方法将用于确定这些碳馏分的可能来源。核心假设是，热带大西洋沉积物中的黑碳来自生物质燃烧，并通过大气沉积传递。最近生物质燃烧产生的碳含有C-14同位素，表明？年轻？(or最近产生的）碳，而来自化石燃料的碳（？（碳？由于放射性衰变没有C-14为了进一步评估该区域黑碳的来源，将在研究航行期间收集水柱和大气颗粒。将通过与瑞典同事的合作确定大气中黑碳颗粒的来源（生物质燃烧或化石燃料排放）。这项研究的更广泛的影响包括高中生通过罗得岛大学的SMILE计划（科学和数学研究性学习体验）的参与。该项目还为研究生和本科生提供培训机会，重点是从代表性不足的群体中招募学生。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Concentrations and source assessment of black carbon across tropical Atlantic air and sedimentPI: Lohmann (URI); co-PI: Pockalny (URI)Black carbon is formed during the incomplete burning of fuels (e.g., the black clouds of smoke emitted by buses and trucks). Black carbon does not degrade easily in the environment and can be transported long distances, even reaching the seafloor. Yet the fluxes of black carbon in the environment are not well known, particularly in the oceans. Rivers are considered the dominant source of black carbon to the oceans. However, recent results suggest that there may be regions of the ocean where the atmospheric delivery of black carbon may be important. This study investigates whether biomass burning (e.g., wildfires) in Africa is a source of black carbon to the tropical Atlantic Ocean. The unique molecular and isotopic properties of black carbon will be used to identify black carbon in the atmosphere, water and sediment in the study region. Sediment, water column and atmospheric particles will be collected during a 3-week research cruise across the tropical Atlantic Ocean. Two different approaches will be used to quantify black carbon in the environment. The research is relevant and timely for our understanding of the carbon cycle, a key component of our ability to forecast climate and its change. The project supports a graduate student and provide opportunities for high school students participating in the SMILE Program (Science and Math Investigative Learning Experiences). This project is jointly funded by the Chemical Oceanography Program and the Established Program to Stimulate Competitive Research (EPSCoR).Surface sediment samples will be collected at ten sites across the tropical Atlantic Ocean in a region known to be impacted by biomass burning events (wildfires) in Africa. Appropriate locations for sediment sampling will be identified using state-of-the-art ship equipment to ensure a successful coring operation. Once collected, the black carbon and organic carbon fractions of the sediment will be isolated and measured. A range of isotopic and molecular marker approaches will be used to identify the likely source of these carbon fractions. The central hypothesis is that the black carbon residing in the sediment of the tropical Atlantic Ocean is derived from biomass burning and delivered through atmospheric deposition. Carbon derived from recent biomass burning contains C-14 isotopes that indicate ?young? (or recently produced) carbon, while carbon from fossil fuels (?old carbon?) has no C-14 due to radioactive decay. To further assess the origin of the black carbon in the region, water column and atmospheric particles will be collected during the research cruise. The origin of the atmospheric black carbon particles (biomass burning or fossil fuel emissions) will be established through a collaboration with colleagues in Sweden. The broader impacts of this research include the engagement of high school students through The SMILE Program (Science and Math Investigative Learning Experiences) at the University of Rhode Island. The project also provides training opportunities for graduate and undergraduate students, with a focus on recruitment of students from under-represented groups.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.