The discovery of the ozone hole The British Antarctic Survey has been monitoring for many years, the total column ozone levels at its base at Halley bay in the antarctica Monitoring data indicate that column ozone levels have been decreasing since 1977. This observation was later confirmed by satellite

Whether and climate Weather is the condition of the atmosphere in terms of temperature, humidity, winds and precipitation Climate is defined as the average weather over various time periods ranging from a few weeks to decades to geological timescales Whether and climate are ultimately determined by location, topography, and the exchange of radiant energy between the Sun, Earth, and space

Greenhouse Glass the material lass transmits Glass absorbs and redirects the longer wavelengths of·nerg Remined longer-wavelength infrard ndation that greenhouse is a made of, 1)transmit \ greenhouse affect short-wavelength visible light, 2)

Air quality and particles Epidemiological(流行病学) evidence associates atmospheric particles with diseases and mortality Particles penetrate the lungs, blocking and irritating aIr passages. Particles themselves could exert toxic effects. ( toxic substances present in the particles [polycyclic Aromatic Hydrocarbons are examples of toxic substances in aerosols.]

Cloud albedo forcing: Cooling Shortwave Radiation The shortwave ays from the Sun are scattered in a cloud; many of the rays return to space. The resulting\cloud albedo forcing taken by itself

Good Ozone and Bad Ozone Stratospheric ozone protect lives on Earth from harmful effects of UV radiation. .Iropospheric ozone: Causing respiratory distress and eye irritation Destroying plants Producing cracks in rubber Ozone is a strong oxidant, reacts with molecules containing C=C double bonds, forming epoxides

Major inorganic gaseous pollutants Carbon monoxide(co) Sulfur dioxide (S02) Nitrogen Oxide(NO, NO2) NOX=NO+NO2 Ozone(03)

Water vapor in the air The volume of Water vapor is variable, depending on temperature, precipitation, rate of evaporation and other factors at a particular location The percentage of water vapor ranges from 0.1- 5%. Generally it is 1-3%(the 3rd most abundant constituents in the air)

The atmosphere The atmosphere is a thin blanket of gas that envelops the earth The gases that make up the atmosphere are held close to the earth by the pull of gravity With increasing distance from the earth's surface, the temperature, density, and composition of the atmosphere gradually change

《环境地球化学》为环境科学专业硕士硏究生的一门学位课,主要介绍化学元素和微 量物质在人类赖以生存的周围环境中的含量、分布特征和来源,生物一非生物复合系统中化 学物质(包括营养物质,主要是针对污染物)的生物地球化学循环的基本过程(包括迁移、 转化和保留等)与反应机制及其与人类健康的关系,揭示人为系统干扰下区域及全球环境系 统的变化规律,为资源合理开发利用,环境质量有效控制及人类生存、健康服务