scholarly journals How winds and river discharge affect circulation in a mesotidal estuary, San Francisco Bay, USA

2022 ◽  
Author(s):  
Qianqian Liu ◽  
Huijie Xue ◽  
Fei Chai ◽  
Zhengui Wang ◽  
Yi Chao ◽  
...  
Keyword(s):  
San Francisco ◽  
River Discharge ◽  
River Flow ◽  
San Francisco Bay ◽  
Integrated System ◽  
Wind Forcing ◽  
Salt Flux ◽  
Tidal Range ◽  
Salt Intrusion

Previous studies suggest importance of wind forcing on salt intrusion length and salt flux in river-dominated microtidal estuaries (with tidal range < 2 m). In this study, we investigate the role of wind forcing on salt intrusion in a mesotidal estuary, San Francisco Bay (SFB), with tidal ranges between 2 m and 4 m, through an open-source model of high transferability, the Semi-implicit Cross-scale Hydroscience Integrated System Model (SCHISM). Meanwhile, we investigate circulation and salinity variation of San Francisco Bay. The model’s performance in hydrodynamics at tidal, spring/neap and seasonal time scales is validated through model-observation comparisons. Through realistically forced and process-oriented experiments, we demonstrate that spring/neap tides can cause fortnightly variations in salinity and currents by modulating vertical mixing and stratification; and seasonal variability of circulation in North Bay is determined by change of river discharge and modified by winds, while in South Bay it is dominated by wind-driven flows. Furthermore, we revealed the role of wind on X2 (the distance from the Golden Gate Bridge to the 2-PSU isohaline at the bottom). The model results show that X2 is primarily influenced by river flow and proportional to river flow to the ¼ power. Meanwhile, wind plays a secondary role in modifying X2 by increasing X2 from 0 to 5 km during low discharge period, while spring/neap tide modulation on X2 is negligible but important for salt balance in sub-regions downstream of X2.

The role of plastic debris in the biogeochemical cycle of mercury in Lake Erie and San Francisco Bay

2021 ◽  
Vol 171 ◽  
pp. 112768
Author(s):  
Katlin L. Bowman ◽  
Carl H. Lamborg ◽  
Alison M. Agather ◽  
Chad R. Hammerschmidt
Keyword(s):  
San Francisco ◽  
Lake Erie ◽  
San Francisco Bay ◽  
Biogeochemical Cycle ◽  
Plastic Debris

A Theory of Political Ambition: Career Choices and the Role of Structural Incentives

1972 ◽  
Vol 66 (1) ◽  
pp. 144-159 ◽  
Author(s):  
Gordon S. Black
Keyword(s):  
San Francisco ◽  
Career Choices ◽  
San Francisco Bay ◽  
Structural Characteristics ◽  
Political Life ◽  
Dropping Out ◽  
Political Ambition ◽  
Community Size ◽  
Political Careers

Office-holders periodically face the problem of choosing among a set of career alternatives, and these alternatives customarily include the choice of dropping out of political life, or seeking reelection, or of choosing to seek higher office. This paper assumes that officeholders behave according to a rational calculus in making such choices, and that the main elements involved in the choice process include the probabilities and values attached by the candidate to his alternatives, and the investments required to obtain these alternatives. Political ambition, or the desire to seek higher office, is shown to develop as a product of the investments that politicians make in their political careers, and the investments are shown to be associated with the structural characteristics of community size and electoral competitiveness. The subjects of the research are 435 city councilmen from 89 cities of the San Francisco Bay Region, and the data include information derived from interviews with the councilmen and aggregate election data collected on each city.

Becoming Craig’s List

2020 ◽  
pp. 19-38
Author(s):  
Jessa Lingel
Keyword(s):  
San Francisco ◽  
Early Phase ◽  
Textual Analysis ◽  
San Francisco Bay ◽  
San Francisco Bay Area ◽  
Bay Area ◽  
Online Marketplace ◽  
Basic Features ◽  
E Mail

This chapter describes craigslist's transformation from an e-mail list to a massively popular online marketplace. It starts with the role of the San Francisco Bay Area in the development of craigslist's purpose and ideology. During this early phase of the tech industry, democratic values of openness and access held sway, values that have shaped craigslist's look and feel ever since. Using interviews and textual analysis of craigslist's public-facing blog, the chapter describes the site's basic features and rules, as well as the company's values and policies. The goal here is to explain how the San Francisco tech scene shaped craigslist's ideas about online publics and politics.

scholarly journals Seasonal stratification and property distributions in a tropical estuary (Cochin estuary, west coast, India)

2013 ◽  
Vol 17 (1) ◽  
pp. 187-199 ◽  
Author(s):  
A. Shivaprasad ◽  
J. Vinita ◽  
C. Revichandran ◽  
P. D. Reny ◽  
M. P. Deepak ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
River Discharge ◽  
River Flow ◽  
Ecological Impact ◽  
Cochin Estuary ◽  
Salt Intrusion ◽  
Salinity Field ◽  
Salt Wedge ◽  
Water Column Stability ◽  
Upwelled Water

Abstract. The intratidal, spring–neap and seasonal variations in stratification were examined in the Cochin estuary. The observations established a strong connection with the distribution of chemical and biological properties. The influence of tides and river discharge forcing in water column stability was quantified using potential energy anomaly (PEA) and stratification parameter. Partially mixed (neap) and well-mixed (spring) conditions during low river discharge (dry) period were altered in monsoon by the salt wedge intrusions. The ecological impact of salt wedge propagation on high tides bringing upwelled water to the system was evident from the bottom hypoxic, high chlorophyll a and nutrient-rich conditions. Phosphate and nitrite concentrations were higher at the bottom saline conditions but silicate and nitrate were clearly supplied by river water. However, during ebb tide this front was driven out of the estuary. The periodic advance and retreat of the salt wedge was inevitable in making the system immune from extended hypoxia/anoxia and maintaining the health of the Cochin estuary. For the seasonally varying river flow in the estuary, salt intrusion receded with increasing river flow in monsoon and rebounded with decreasing river flow in dry season. During monsoon, the intense flushing and reduction in salinity field expansion seemed to be responsible for the limited chlorophyll a levels along the surface of the Cochin estuary.

scholarly journals The Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California

Geosphere ◽  
2017 ◽  
Vol 13 (2) ◽  
pp. 269-286
Author(s):  
R.C. Jachens ◽  
C.M. Wentworth ◽  
R.W. Graymer ◽  
R.A. Williams ◽  
D.A. Ponce ◽  
...  
Keyword(s):  
San Francisco ◽  
San Andreas Fault ◽  
San Francisco Bay ◽  
Fault System ◽  
San Andreas ◽  
San Andreas Fault System

scholarly journals Situating Sustainability in the Luxury City

2018 ◽  
pp. 180-195 ◽  
Keyword(s):  
Environmental Justice ◽  
San Francisco ◽  
Social Relations ◽  
San Francisco Bay ◽  
San Francisco Bay Area ◽  
Global Cities ◽  
Critical Approach ◽  
Bay Area ◽  
Political Ecologies

This chapter seeks to situate sustainability within particular epistemological fields and communities in order to understand the growing contentiousness between rival versions of the concept. Focusing on the famously green yet increasingly unaffordable 'luxury city' of San Francisco Bay Area, it explores how these epistemological formations are quite literally 'situated' geographically, shaped by and shaping of the places, communities, social relations and political ecologies in which they emerge. It argues that as investments into greening are increasingly designed to serve powerful economic actors in aspiring global cities and regions like San Francisco, prevailing, historically and culturally rooted understandings of sustainability are often reframed and redefined in a more instrumentalist, market-oriented direction. The latter approach comes into conflict with classic understandings of the “3 E’s” of sustainability—in which economic concerns are balanced with and equal to those of equity and ecology. And they pose fundamental questions about what and how environmental justice politics are to be practiced today. The chapter aims to contribute to such emergent politics and scholarship by advancing a critical approach to "sustainability" that takes seriously the role of power, place, and history in shaping our use of the term.

Sign in / Sign up

Export Citation Format

Share Document