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Publications

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Long-term changes in kelp forests in an inner basin of the Salish Sea

Kelp forests form an important biogenic habitat that responds to natural and human drivers. Global concerns exist about threats to kelp forests, yet long-term information is limited and research suggests that trends are geographically distinct. We examined distribution of the bull kelp Nereocystis luetkeana over 145 years in South Puget Sound (SPS), a semi-protected inner basin in a fjord estuary
Authors
H.D. Berry, T.F. Mumford, M. Calloway, L. Ferrier, B. Christiaen, Nathan R. vanArendonk, Eric E. Grossman, P. Dowty

The Mars 2020 Perseverance rover mast camera zoom (Mastcam-Z) multispectral, stereoscopic imaging investigation

Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission’s Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 μrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 μrad/pixel). The camera
Authors
J. F. Bell, J. N. Maki, G. L. Mehall, M. A. Ravine, M. A. Caplinger, Z. J. Bailey, S. Brylow, J. A. Schaffner, K. M. Kinch, M. B. Madsen, A. Winhold, A. G. Hayes, P. Corlies, C. Tate, M. Barrington, E. Cisneros, E. Jensen, Katy L. Parise, Kelon Crawford, C. Rojas, L. Mehall, J. Joseph, J. B. Proton, N. Cluff, R. G. Deen, B. Betts, Edward A. Cloutis, A. J. Coates, Anthony Colaprete, K. S. Edgett, B. L. Ehlmann, Sarah A. Fagents, J. P. Grotzinger, C. Hardgrove, Kenneth E. Herkenhoff, Briony H. N. Horgan, R. Jaumann, J. R. Johnson, M. T. Lemmon, G. Paar, M Caballo-Perucha, S. Gupta, C Traxler, F. Preusker, M. S. Rice, M. S. Robinson, N. Schmitz, R. Sullivan, M. J. Wolff

The contribution of currents, sea-swell waves, and infragravity waves to suspended-sediment transport across a coral reef-lagoon system.

Coral reefs generate substantial volumes of carbonate sediment, which is redistributed throughout the reef‐lagoon system. However, there is little understanding of the specific processes that transport this sediment produced on the outer portions of coral reefs throughout a reef‐lagoon system. Furthermore, the separate contributions of currents, sea‐swell waves, and infragravity waves to transport
Authors
Andrew Pomeroy, Curt Storlazzi, Kurt J. Rosenberger, Ryan Lowe, Jeff Hansen, Mark L. Buckley

Electrical conductivity of the lithosphere-asthenosphere system

Electromagnetic geophysical methods image the electrical conductivity of the subsurface. Electrical conductivity is an intrinsic material property that is sensitive to temperature, composition, porosity, volatile and/or melt content, and other physical properties relevant to the solid Earth. Therefore, imaging the electrical structure of the crust and mantle yields valuable information on the phys
Authors
Samer Naif, Kate Selway, Benjamin Scott Murphy, Gary D. Egbert, Anne Pommier

The application of ensemble wave forcing to quantify uncertainty of shoreline change predictions

Reliable predictions and accompanying uncertainty estimates of coastal evolution on decadal to centennial time scales are increasingly sought. So far, most coastal change projections rely on a single, deterministic realization of the unknown future wave climate, often derived from a global climate model. Yet, deterministic projections do not account for the stochastic nature of future wave conditi
Authors
Sean Vitousek, Laura Cagigal, Jennifer Montaño, Ana Rueda, Fernando Mendez, Giovanni Coco, Patrick L. Barnard

Availability of subsurface water-ice resources in the northern mid-latitudes of Mars

Multiple nations and private entities are pushing to make landing humans on Mars a reality. The majority of proposed mission architectures envision ‘living off the land’ by leveraging Martian water-ice deposits for fuel production and other purposes. Fortunately for mission designers, water ice exists on Mars in plentiful volumes. The challenge is isolating accessible ice deposits within regions t
Authors
Gareth A Morgan, Nathaniel E Putzig, Matthew R Perry, Hanna G Sizemore, Ali M Bramson, Eric I Petersen, Zach M Bain, David M H Baker, Marco Mastrogiuseppe, Rachel H Hoover, Isaac B. Smith, Asmin V Pathare, Colin M. Dundas, Bruce A Campbell

Forecasting the frequency and magnitude of postfire debris flows across southern California

Southern California has a long history of damaging debris flows after wildfire. Despite recurrent loss, forecasts of the frequency and magnitude of postfire debris flows are not available for the region like they are for earthquakes. Instead, debris flow hazards are typically assessed in a reactive manner after wildfires. Such assessments are crucial for evaluating debris flow risk by postfire eme
Authors
Jason W. Kean, Dennis M. Staley

Can modeling the geologic record contribute to constraining the tectonic source of the AD 1755 Great Lisbon earthquake?

The precise location of the seismic source of 1755 CE Great Lisbon earthquake is still uncertain. The aim of this work is to use an onland sedimentary record in southern Portugal to test and validate seismic sources for the earthquake. To achieve this, tsunami deposit thicknesses from over 150 cores collected at Salgados in southern Portugal were compared to the results of a tsunami sediment trans
Authors
Francisco Dourado, Pedro JM Costa, SeanPaul La Selle, Caesar Andrade, Ivana Bosnic, Guy R. Gelfenbaum

River floodplain abandonment and channel deepening coincide with the onset of clear-cut logging in a coastal California redwood forest

Changes in both land use and climate can alter the balance of transport capacity and sediment supply in rivers. Hence, the primary driver of recent incision or aggradation in alluvial channels is often unclear. The San Lorenzo River on the central coast of California is one location where both climate and land use—specifically, clear-cut forestry of coastal redwoods—could explain recent vertical i
Authors
William A. L. Chapman, Noah J. Finnegan, Allison M. Pfeiffer, SeanPaul La Selle

In-situ monitoring of infiltration-induced instability of I-70 embankment west of the Eisenhower-Johnson Memorial Tunnels, phase III

A new methodology that uses recent advances in unsaturated soil mechanics and hydrology was developed and tested. The approach consists of using soil suction and moisture content field information in the prediction of the likelihood of landslide movement. The testing ground was an active landslide on I-70 west of the Eisenhower/Johnson Memorial Tunnels. A joint effort between Colorado School of Mi
Authors
Alexandra Wayllace, Ning Lu, Benjamin B. Mirus

Fluid-earthquake and earthquake-earthquake interactions in southern Kansas, USA

An increase in injection activity associated with energy production in southern Kansas starting in 2013 has been linked to the occurrence of more than 130,000 earthquakes (M −1.5 to 4.9) between 2014 and 2017. Studies suggest that the dramatic increase in seismicity rate is related to wastewater injection into the highly permeable Arbuckle formation. Most of the seismicity is located in the underl
Authors
A. Verdecchia, Elizabeth S. Cochran, R. M Harrington

Time since burning and rainfall characteristics impact post-fire debris flow initiation and magnitude

The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote elevated rates of runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Debris flows are most common in the year immediately following wildfire, but temp
Authors
Luke A. McGuire, Francis K. Rengers, Nina S. Oakley, Jason W. Kean, Dennis M. Staley, Hui Tang, Marian de Orla-Barile, Ann M. Youberg