House Panel to Investigate Report That Cabinet Official Coerced NOAA Chief

The House Science Committee opened an inquiry into a report that the commerce secretary threatened firings at the agency after some forecasters contradicted President Trump.

How Hydrologic Connectivity Regulates Water Quality in River Corridors

Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off‐channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream flow and the exchange of water with the bed, banks, and floodplains. The degree of connectivity directly influences downstream water quality — too little connectivity limits the amount of river water exchanged and leads to biogeochemically inactive water storage, while too much connectivity limits the contact time with sediments for reactions to proceed. Using a metric of reaction significance based on river connectivity, we provide evidence that intermediate levels of connectivity, rather than the highest or lowest levels, are the most efficient in removing nitrogen from Northeastern United States' rivers. Intermediate connectivity balances the frequency, residence time, and contact volume with reactive sediments, which can maximize the reactive processing of dissolved contaminants and the protection of downstream water quality. Our simulations suggest denitrification dominantly occurs in riverbed hyporheic zones of streams and small rivers, whereas vertical turbulent mixing in contact with sediments dominates in mid‐size to large rivers. The metrics of connectivity and reaction significance presented here can facilitate scientifically based prioritizations of river management strategies to protect the values and functions of river corridors.

Climate Denialist to Depart White House National Security Council

William Happer, a National Security Council adviser who tried unsuccessfully to create a federal panel to attack climate science, plans to leave the White House. 

Vapor-Pressure Pathways Initiate but Hydrolysis Products Dominate the Aerosol Estimated from Organic Nitrates

Organic nitrates contribute significantly to the total organic aerosol burden. However, the formation and loss mechanisms of particulate organic nitrates (PONs) remain poorly understood. In this study, with the CMAQ modeling system, we implement a detailed biogenic volatile organic carbon gas phase oxidation mechanism and an explicit representation of multiphase organic nitrate formation and loss, including both aqueous-phase uptake and vapor-pressure driven partitioning into organic aerosol as well as condensed-phase reactions. We find vapor-pressure dependent partitioning is the leading mechanism for formation of PONs and hydrolysis is a major loss mechanism for PON resulting in substantial amounts of organic aerosol that originate as an organic nitrate. Partitioning and hydrolysis together can produce high concentrations (up to 5 μg/m3) of PON-derived aerosols over the southeast United States. The main source of PON-derived aerosols is monoterpene nitrates that have been chemically processed to lose their nitrate functionality through aqueous chemistry. In contrast, the major portion of aqueous aerosol and in-cloud PON, which retains its nitrate moiety, are soluble isoprene nitrates. We evaluate the model using the observations from the Southern Oxidant and Aerosol Study (SOAS) campaign in the Southeast US in summer 2013 and show implementing aerosol-phase pathways for organic nitrates dramatically improves the magnitude of total alkyl nitrates (ANs) in CMAQ. The contribution of PONs to the total ANs at the SOAS site is estimated to be ∼20%, a value in the range of the measurements. The predicted AN composition is shifted from monoterpene to isoprene and anthropogenic organic nitrates.

Phosphate recovery from water using cellulose enhanced magnesium carbonate pellets: Kinetics, isotherms, and desorption

Phosphorus is an essential and limited nutrient that is supplied by a depleting resource, mineral phosphate rock. Eutrophication is occurring in many water bodies which provides an opportunity to recover this nutrient from water. One method of recovery is through adsorption; this study focused on fabricating a porous and granular adsorptive material for the removal and recovery of phosphate. Magnesium carbonate was combined with cellulose in varying weight ratios (0, 5, 10, 15, 20%) to synthesize pellets, which were then calcined to increase internal surface area. Physiochemical properties such as surface area, surface morphology, elemental composition, and crystal structure of the materials were characterized using Brunauer, Emmett and Teller (BET) surface area analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The pellet proved to be uniform in composition and an increase in BET surface area correlated with an increase in cellulose content until pellet stability was lost. Phosphate adsorption using the pellets was studied via batch kinetics and sorption isotherms. The pseudo-second-order kinetics model fit best suggesting that the adsorption occurring was chemisorption. The isotherm model that fit best was the Langmuir isotherm, which showed that the maximum equilibrium adsorption capacity increased with an increase in cellulose content between 10% and 20%. The average adsorption capacity achieved in the triplicate isotherm study was 96.4 mg g-1 for pellets synthesized with 15% cellulose. Overall, using cellulose and subsequent calcination created additional internal surface area for adsorption of phosphate and suggests that granular materials can be modified for efficient removal and recovery of phosphate from water.

Why NOAA Matters

Also this week, how to get a tax break for installing solar panels

Experiments with the LECO Pegasus® Gas Chromatograph/Time-of-Flight Mass Spectrometer Phase 2: 2D Fast GC Separations

Gas chromatography/mass spectrometry (GC/MS) is the method of choice for the analysis of volatile and semivolatile organic compounds in environmental samples. In this study, the LECO Pegasus® 4D GC/TOF-MS was used in the 2D mode to detect chemical warfare agents (CWAs) and to compare this instrument's performance, with regards to speed of analysis, instrument detection limits, and various matrices to conventional quadrupole-based GC/MS.