This is the pre-event announcement for an online lecture by Itsuki Handoh, Associate Professor at the Research Institute for Humanity and Nature, Kyoto.

Here is the full talk info:

Phosphorus and Chemical Pollution as Global Catastrophic Risks
Tuesday-Wednesday 25-26 June, midnight GMT (Wednesday 9:00AM JST/Tokyo; Tuesday 20:00 New York; Tuesday 17:00 Los Angeles)
To be held online via Skype or equivalent. RSVP required by email to Seth Baum (seth [at] gcrinstitute.org). Space is limited.

Abstract:

The so-called global environmental problems are a manifestation of adverse effects of the interactions between humanity and nature. Some of the problems are attributed to a chemical imbalance in the Earth system. Marine pollution is such an example. Excessive inputs of particular chemicals (of both natural and anthropogenic origins) into the oceans could trigger marine pollution. In order to better understand and characterize the chemical imbalance and its relation to Global Catastrophic Risk (GCR), we discuss the following two case studies with particular reference to the recently-emerged Planetary Boundaries (PBs) paradigm: phosphorus biogeochemical cycles and chemical pollution caused by persistent organic pollutants (POPs).

The biggest concern for phosphorus may be an oceanic, biogeophysical threshold resulting in massive eutrophication, and more importantly, an oceanic anoxic event (OAE) in which low ocean oxygen concentrations result in massive species extinctions. A modeling study suggested a sustained increase of terrestrial phosphorus flows into the oceans could trigger an OAE, though significant uncertainty remains. There may not be enough phosphorus available to trigger an OAE, while the depletion of phosphorus reserves may be a more serious problem for humanity than OAE. Human dimensions of phosphorus impacts are addressed.

Similarly for phosphorus, chemical pollution has been identified as one of the PBs, but the control variable has not yet been determined. Chemical pollution is commonly understood to have mainly aggregative effects, with localized pollution poisoning nearby humans and other organisms. However, chemical pollution can also have systemic effects, both because the chemicals can spread around the world and because their local impacts can have systemic consequences such as disruptions to markets for products that become contaminated with chemical pollutants. Using Finely-Advanced Transboundary Environmental model (FATE), which is capable of predicting the exposure of several POPs, such as polychlorinated biphenyls (PCBs), to marine organisms, and a compiled data set on mass disease and mortality events of higher trophic-level marine mammals, we critically assess the response of an ecological integrity to environmental risk associated with POPs.