This study demonstrates the utility of applying freely available synthetic-aperture radar (SAR) data from the Sentinel-1 satellite within a Google Earth Engine (GEE) HYDRAfloods framework for detecting and mapping flooded areas on a small island. The island of Trinidad, situated in the south eastern region of the Caribbean, experienced its largest flooding event in the past 50 years in October 2018. This was followed by an event of similar magnitude, just 4 years later. GEE was utilized to detect water areas in radar images that were captured during the period of the flood. Flood water areas were separated from permanent water areas by also processing a collection of non-event images. Flood distribution maps were then created and total flooded area was calculated for the study region for both years. A buildings polygon layer derived by Google, was then overlayed on the flood area polygons to visually assess the impacts on infrastructure. The methodology applied in this study was effective for detecting and mapping the flooded areas, however, the temporal resolution (revisit-time) of the Sentinel-1 satellite was still a major limitation, since no images of the peak flooding period of either event were captured.

The annual adverse effects of pollution are on the order of 10% of world GDP. Many approaches are used or have been proposed to control the growing pollution problem, but none of them allows for efficient pollution control in settings in which the marginal cost of pollution is increasing and polluters are better informed than regulators about the costs of abatement. In particular, taxes, quantity restrictions, uniform-price auctions, and the usual implementations of discriminatory auctions (e.g., by the U.S. Environmental Protection Agency) in general lead to inefficient allocations. We propose a simple primary market mechanism, True-Cost Pay as Bid (TCPAB), that implements efficient pollution control and does not depend on how much information regulators have about firms' abatement costs. When polluters have symmetric information and the marginal cost of pollution is known, TCPAB implements an efficient primary market allocation. When the marginal cost of pollution is uncertain, TCPAB implements the most efficient allocation possible without further information on the true marginal cost. When polluters have asymmetric information about their opponents' costs of abatement, the inefficiency of TCPAB is small provided the informational asymmetry is not too large. TCPAB's favorable properties extend to dynamic environments provided limits are placed on the trading of permits across time. We also discuss how an adoption of TCPAB may facilitate international bargaining over emissions abatement.

The pay-as-bid auction is a prominent format for selling homogenous goods such as treasury securities and commodities. We analyze the optimal design of pay-as-bid auctions allowing for asymmetric information. We show that supply transparency and full disclosure are optimal in pay-as-bid, though not necessarily in uniform-price (the main alternative auction format). Pay-as-bid is revenue dominant and might be welfare dominant. Under assumptions commonly imposed in empirical work, the two formats are revenue and welfare equivalent.

Pay-as-bid auctions are frequently implemented when a single seller allocates multiple units of a homogeneous good, and are commonly used to sell treasury securities, allocate electricity generation, and distribute emissions credits. In this auction format, bidders submit demand curves to a seller who uses these stated demands to compute market-clearing quantities, then allocates each bidder her associated quantity while charging the entire area under her stated demand curve. Except in parameterized settings, little has been known about equilibrium strategies in pay-as-bid auctions.

It is known that pay-as-bid auctions admit pure-strategy equilibria when bidders have private information, as long as the space of available strategies is discrete; except in parameterized settings, there is no tractable method for computing these equilibria. Continuous approximations frequently prove useful when equilibria are difficult to compute in underlying discretized models, however the presence of payoff discontinuities in pay-as-bid auctions implies that current equilibrium existence results cannot be directly applied to the natural continuous approximation of the pay-as-bid auction.