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J. Monnier

Publications and source records attributed to J. Monnier.

2 recordsLinked to original sources

Astronomical optical interferometry from the lunar surface: High sensitivity at sub-miliarcsecond scales

The lunar surface is a compelling opportunity for large, distributed optical facilities, with significant advantages over orbital facilities for high spatial resolution astrophysics. Serious development of mission concepts is timely because of the confluence of multiple compelling factors. First, lunar access technology is maturing rapidly, in the form of both US uncrewed and crewed landers, as well as international efforts. Accompanying that has been a definitive maturation of astronomical optical interferometry technologies at Earth-based facilities over the past three decades – opening exquisitely sharp views on the universe previously unob- tainable, though limited at present by the Earth’s atmosphere. Importantly, the increasing knowledge and experience base about lunar surface operations indicates it is not just suitable but highly attractive for lunar telescopes arrays.

Report

Estimating river discharge with swath altimetry: A proof of concept using AirSWOT observations

The forthcoming Surface Water and Ocean Topography (SWOT) satellite mission will provide global measurements of the free surface of large rivers, providing new opportunities for remote sensing‐derived estimates of river discharge in gaged and ungaged basins. SWOT discharge algorithms have been developed and benchmarked using synthetic data but remain untested on real‐world swath altimetry observations. We present the first discharge estimates from AirSWOT, a SWOT‐like airborne Ka‐band radar, using 6 days of measurements over a 40‐km segment of the Willamette River in Oregon, USA. The three evaluated discharge algorithms estimated discharge with normalized root‐mean‐square errors of 10–31% when compared with in situ gage data but were sensitive to an initial estimate of mean annual discharge. Our results show that these discharge algorithms provide reliable discharge estimates on remotely sensed data at SWOT‐like spatial scales while highlighting the need for further algorithm sensitivity tests.

Oregon