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Clemesha, RES, Gershunov A, Iacobellis SF, Cayan DR.  2017.  Daily variability of California coastal low cloudiness: A balancing act between stability and subsidence. Geophysical Research Letters. 44:3330-3338.   10.1002/2017gl073075   AbstractWebsite

We examine mechanisms driving daily variability of summer coastal low cloudiness (CLC) along the California coast. Daily CLC is derived from a satellite record from 1996 to 2014. Atmospheric rather than oceanic processes are mostly responsible for daily fluctuations in vertical stability that dictate short-period variation in CLC structure. Daily CLC anomalies are most strongly correlated to lower tropospheric stability anomalies to the north. The spatially offset nature of the cloud-stability relationship is a result of the balancing act that affects low cloudiness wherein subsidence drives increased stability, which promotes cloudiness, but too much subsidence limits cloudiness. Lay explanations claim that high inland temperatures pull in CLC, but such a process presumably would have the high temperatures directly inland. Rather, we find that the spatially offset associations between CLC and atmospheric circulation result in positive correlations between CLC and inland surface temperature anomalies to the north.

Clemesha, RES, Gershunov A, Iacobellis SF, Williams AP, Cayan DR.  2016.  The northward march of summer low cloudiness along the California coast. Geophysical Research Letters. 43:1287-1295.   10.1002/2015gl067081   AbstractWebsite

A new satellite-derived low cloud retrieval reveals rich spatial texture and coherent space-time propagation in summertime California coastal low cloudiness (CLC). Throughout the region, CLC is greatest during May-September but has considerable monthly variability within this summer season. On average, June is cloudiest along the coast of southern California and northern Baja, Mexico, while July is cloudiest along northern California's coast. Over the course of the summer, the core of peak CLC migrates northward along coastal California, reaching its northernmost extent in late July/early August, then recedes while weakening. The timing and movement of the CLC climatological structure is related to the summer evolution of lower tropospheric stability and both its component parts, sea surface temperature and potential temperature at 700hPa. The roughly coincident seasonal timing of peak CLC with peak summertime temperatures translates into the strongest heat-modulating capacity of CLC along California's north coast.

Rick, TC, Sillett TS, Ghalambor CK, Hofman CA, Ralls K, Anderson RS, Boser CL, Braje TJ, Cayan DR, Chesser RT, Collins PW, Erlandson JM, Faulkner KR, Fleischer R, Funk WC, Galipeau R, Huston A, King J, Laughrin L, Maldonado J, McEachern K, Muhs DR, Newsome SD, Reeder-Myers L, Still C, Morrison SA.  2014.  Ecological change on California's Channel Islands from the Pleistocene to the Anthropocene. Bioscience. 64:680-692.   10.1093/biosci/biu094   AbstractWebsite

Historical ecology is becoming an important focus in conservation biology and offers a promising tool to help guide ecosystem management. Here, we integrate data from multiple disciplines to illuminate the past, present, and future of biodiversity on California's Channel Islands, an archipelago that has undergone a wide range of land-use and ecological changes. Our analysis spans approximately 20,000 years, from before human occupation and through Native American hunter-gatherers, commercial ranchers and fishers, the US military, and other land managers. We demonstrate how long-term, interdisciplinary research provides insight into conservation decisions, such as setting ecosystem restoration goals, preserving rare and endemic taxa, and reducing the impacts of climate change on natural and cultural resources. We illustrate the importance of historical perspectives for understanding modern patterns and ecological change and present an approach that can be applied generally in conservation management planning.