Many of our daily activities can potentially alter environmental balances,but too often we ignore relationships among people,other living creatures,and surroundings.The purpose of this column will dedicate to make people arcoss the country more aware of the importance of protecting environment.

• Acid Rain - You first need to understand Acid Deposition: a complex chemical and atmospheric phenomenon that occurs when emissions of sulfur and nitrogen compounds and other substances are transformed by chemical processes in the atmosphere, often far from the original sources, and then deposited on earth in either wet or dry form. The wet forms (precipitation) are popularly called "acid rain" and fall as rain, snow, or fog. The dry forms are acidic gases or particulates.
• By-product - Materials, other than the intended product, generated as a result of an industrial process.
• Climate Change - this term is commonly used interchangeably with "global warming" and "the greenhouse effect," but is a more descriptive term. Climate change refers to the buildup of man-made gases in the atmosphere that trap the sun's heat, causing changes in weather patterns on a global scale. The effects include changes in rainfall patterns, sea level rise, potential droughts, habitat loss, and heat stress. The greenhouse gases of most concern are carbon dioxide, methane, and nitrous oxides. If these gases in our atmosphere double, the earth could warm up by 1.5 to 4.5 degrees by the year 2050, with changes in global precipitation having the greatest consequences.
• Conservation - Preserving and renewing natural resources to assure their highest economic or social benefit over the longest period of time. Clean rivers and lakes, wilderness areas, a diverse wildlife population, healthy soil, and clean air are natural resources worth conserving for future generations.
• Disposal - The discharge, deposit, injection, dumping, spilling, leaking, or placing of any solid waste or hazardous waste into the environment (land, ground water, and air).
• Environmental Assessment (EA) - A preliminary, written, environmental analysis required by NEPA (see the Federal Law section) to determine whether a federal activity such as building airports or highways would significantly affect the environment
• Garbage - Food waste (animal and vegetable) resulting from the handling, storage, packaging, sale, preparation, cooking, and serving of foods.

• There are three kinds of ultraviolet (UV) radiation -- UVA, which penetrates clouds and ozone; UVB, which is mostly blocked by ozone and clouds; and UVC, which is completely absorbed by the ozone layer and the atmosphere.
• Hippos secrete a pink, natural sunscreen from their skin.
• When you're out in the sun, you should use a sunscreen with a sun protection factor or "SPF" of at least 15.
• You should limit the amount of time you spend in the sun between 10 am and 4 pm.
• It's good to wear a hat with a wide brim when you're out in the sun.
• The earth has a protective shield, the stratospheric ozone layer, that protects us all from the effects of UV radiation.
• Out of every 10 million air molecules, about 2 million are normal oxygen, but only three molecules are ozone.
• The UV Index, a forecast of the strength of UV radiation, is reported daily on a scale of 0 to 10+. The higher the UV Index number, the more sun protection you need.
• Each year, more than 1.3 million Americans get skin cancer. Cover up and be SunWise!
• You should always put sunscreen on at least 15 to 20 minutes before going outside.
• Remember to reapply sunscreen every couple of hours, or after perspiring or swimming.
• People generally get 80% of their lifetime sun exposure by the time they are 18.

China. Division Of Environmental Economics,Chinese Academy Of  Land And Resource Economics. 

 P.O.BOX 259 Beijing 101149

 For more information about this content contact:  FengChunTao

   Last updated: 3 July 2001