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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Earth and Space Sciences · 术语表

什么是 Front？

又称： cold front · warm front

Definition 25.2 Primary & Middle School Earth and Space Sciences · 第 25 章 — Air Masses, Fronts and Weather Maps

A front is the boundary at the ground between two air masses of different temperature and humidity. At a cold front, cold air pushes into warmer air and takes its place; at a warm front, warm air pushes into colder air and takes its place.

A cold front seen from the side (heights much exaggerated). The cold air pushes under the warm air like a wedge; the warm air is lifted steeply and builds towering clouds.

A warm front seen from the side (heights much exaggerated). The warm air climbs slowly over the cold air; its clouds come lower and thicker as the front approaches, and the rain is long and steady.

示例

Example 25.7 (Reading a barometer’s record)

For the first 8 hours the pressure rises to about $1031\,\mathrm{hPa}$ : the anticyclone passes over S, with settled weather. Then it falls for 30 hours, by about $45\,\mathrm{hPa}$ : the depression is coming. It falls fastest a few hours before the warm front passes, more slowly in the warm air behind it, and reaches its lowest, about $986\,\mathrm{hPa}$ , just as the cold front passes. Then it rises: the depression is moving away, and the cooler, clearer air behind the cold front arrives.

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