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9. Visualizing changes to US federal environmental agency websites, 2016–2020.

Author

Nost, Eric, Gehrke, Gretchen, Poudrier, Grace, Lemelin, Aaron, Beck, Marcy, and Wylie, Sara

Subjects
*GOVERNMENT websites, *ENVIRONMENTAL agencies, *GOVERNMENT agencies, *PRESIDENTIAL administrations, *CLIMATE change denial
Abstract

Websites have become the primary means by which the US federal government communicates about its operations and presents information for public consumption. However, the alteration or removal of critical information from these sites is often entirely legal and done without the public's awareness. Relative to paper records, websites enable governments to shape public understanding in quick, scalable, and permissible ways. During the Trump administration, website changes indicative of climate denial prompted civil society organizations to develop tools for tracking online government information sources. We in the Environmental Data & Governance Initiative (EDGI) illustrate how five data visualization techniques can be used to document and analyze changes to government websites. We examine a large sample of websites of US federal environmental agencies and show that between 2016 and 2020: 1) the use of the term "climate change" decreased by an estimated 38%; 2) access to as much as 20% of the Environmental Protection Agency's website was removed; 3) changes were made more to Cabinet agencies' websites and to highly visible pages. In formulating ways to visualize and assess the alteration of websites, our study lays important groundwork for both systematically tracking changes and holding officials more accountable for their web practices. Our techniques enable researchers and watchdog groups alike to operate at the scale necessary to understand the breadth of impact an administration can have on the online face of government. [ABSTRACT FROM AUTHOR]

Published
2021
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13. Mercury Cycling in the Marine Environment: Insights from Hg stable isotopes.

Author

Gehrke, Gretchen E.

Subjects
Mercury, Isotopes
Abstract

Mercury (Hg) is a globally distributed trace metal with natural and anthropogenic sources to the environment. Marine reservoirs provide the primary vector of human exposure to Hg and are integral to global Hg cycling. To elucidate environmental influences on marine Hg cycling and discern prominent sources of Hg to modern estuaries, Hg isotopic compositions and concentrations were analyzed in pre-Industrial and modern marine sediments. Mid-Pleistocene Mediterranean Sea sapropels had Hg concentrations (HgT) 6-fold higher than non-sapropels, reaching 400 ng/g. Comparison between Hg and other trace metals indicated that elevated primary productivity promoted sediment Hg accumulation. In the Baltic Sea, surface sediments had HgT up to 150 ng/g and 3-times higher than co-located pre-Industrial sediments, and Hg isotope analysis demonstrated that an additional source of Hg also contributed to increased sediment HgT. Pre-Industrial and modern Baltic Sea sediment Hg can be explained by mixing between marine Hg (delta-202Hg = -1.1 permil) and anthropogenic Hg (delta-202Hg = -0.5 permil). In San Francisco Bay (SF Bay), surface sediment HgT ranged from 160 to 850 ng/g, with highest HgT in Central and Lower South Bay. The Hg isotopic compositions of sediments displayed a geographic gradient, with delta-202Hg values ranging from -0.3 permil in the south to -1.0 permil in the north. Fluvial sediments in southern and northern tributaries had delta-202Hg values of -0.3 and -0.9 permil, and demonstrated that two large regional sources dominated Hg input into SF Bay. Small fish co-located with sediments demonstrated a similar spatial gradient in Hg isotope compositions, with delta-202Hg values ranging from +0.6 to -0.3 permil. A consistent offset between sediment and fish delta-202Hg values demonstrated that sediments were the primary source of Hg to SF Bay small fish. Additionally, this work used Hg isotopes to identify perturbations to the global Hg cycle at the Paleocene-Eocene Boundary (PEB). A large increase in HgT and delta-202Hg values was observed at the PEB and provides the basis for future Hg isotope research in paleoceanography.

Published
2011

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