MIT Sea Grant has selected three research projects for funding from our annual request for proposals. The projects focus on developing new ocean acidification sensor technology and using modeling techniques to consolidate historical data to inform future coastal ocean acidification monitoring. The three projects are described below; Towards a Cost-Effective Monitoring System of Coastal Ocean Acidification in the US North EastThemistoklis Sapsis, Massachusetts Institute of TechnologyIt is important to accurately monitor coastal acidification (COA) in the coastal environment as this area is particularly affected by anthropogenic inputs. However, distributing pH sensors throughout Boston Harbor, Mass Bay or the Gulf of Maine with pH sensors would be impractical and very expensive. Computer simulations can help alleviate much of the cost and increase accurate predictions but requires validated, biochemical simulation models for the Northeast. We propose an integrated methodology that will combine and analyze all available information from monitoring stations in Mass Bay, Boston Harbor and their tributaries. We will use deep Gaussian Processe to blend information from diverse sources at variable fidelity in a multi-fidelity Bayesian framework, where all uncertainties are accounted for in the final prediction. Increased development of coastal communities has brought more runoff, sedimentation, nutrients and contaminants, and habitat degradation in coastal areas. Integrating multi-fidelity data with the biogeochemical-augmented coastal model (FVCOM-ERSEM) will result in highly accurate predictions of COA that will enable improved, cost-effective management of coastal resources, and support environmental preservation and remediation efforts.Developing a Miniaturized In-situ Sensor Technology for Simultaneous Measurements of Seawater Dissolved Inorganic Carbon and pCO2Zhaohui ‘Aleck’ Wang of Woods Hole Oceanographic InstitutionThe development of carbon sensors to monitor and study ocean acidification is widely recognized as a research priority at this time in history. Dissolved inorganic carbon (DIC) and partial pressure of CO2 (pCO2) are desirable parameters for accurately characterizing the marine CO2 system. This project will develop a miniaturized, in-situ sensor, Channelized Optical System II (CHANOS II) for simultaneous, spectrophotometric measurements of seawater DIC and pCO2 with high frequency (~1 Hz) for up to 1000 m of water depth. Built on the success of the original CHANOS, CHANOS II will develop a miniaturized fluidic CO2 equilibrating manifold for both DIC and pCO2 channels, applying miniature pumps and switches to dramatically reduce sensor size, power consumption, and cost, and improve robustness. CHANOS II will be capable of making high-quality measurements on both stationary and mobile platforms, such as buoys, profilers, and autonomous underwater vehicles (AUVs). The deployable time depends on what platforms it will be on. For stationary platforms, it can be up to 4 months at hourly sampling interval; for mobile platforms, it can be up to one week continuous measurements. Sensors for Measuring Carbon Dioxide, Bicarbonate, and pH in the Ocean Timothy Manning Swager, Massachusetts Institute of TechnologyThis proposal seeks to develop small, economical, low-power sensors to be deployed in networks in coastal marine eco-systems to record levels of CO2, CO3H-, and pH. The sensors will use a hybrid of silicon-based, field-effect transistors and electroactive organic molecules/polymers. These organic materials are designed to have variable Fermi levels that change with pH and CO3H- concentrations. The new sensors can be used for persistent, distributed monitoring of coastal waters needed to understand the effects of river emissions and atmospheric perturbations on ocean ecology. Shallow regions are particularly sensitive to these chemical changes in the water; they are habitat to abundant shell fish populations and also provide a breeding ground for economically important fish species and other sea life. The sensors will allow for the collection of critical spatial-temporal data to be used in models that can explain the origins of chemical changes. The projects are expected to run between spring 2017 and Jan. 31, 2019.See a full list of MIT Sea Grant’s active projects.