3.2

The UV, visible, and infrared energy that reaches the atmosphere lights the earth during daytime, warms the air, and evaporates and cycles water through the biosphere. Approximately 1% of this incoming energy generates winds. Green plants, algae, and some types of bacteria use less than 0.1% of it to produce the nutrients they need through photosynthesis, and in turn to feed animals that eat plants and flesh.
Of the total solar radiation intercepted by the earth, about 1% reaches the earth’s surface, and most of it is then reflected as longer-wavelength infrared radiation. As this infrared radiation travels back up through the lower atmosphere toward space, it encounters the greenhouse gases such as water vapor, carbon dioxide, methane, nitrous oxide and ozone. It causes these gaseous molecules to vibrate and release infrared radiation with even longer wavelengths. The vibrating gaseous molecules then have higher kinetic energy, which helps to warm the lower atmosphere and the earth’s surface. Without this natural greenhouse effect, the earth would be too cold to support the formsof life we find here today.
紫外線，可見光和紅外能量到達地球大氣層燈白天，溫暖的空氣和水的蒸發和週期通過生物圈。大約1 ％的能源生成傳入風。綠色植物，藻類和某些類型的細菌使用小於0.1 ％的生產他們所需要的營養物質通過光合作用，從而為飼料的動物，吃植物和肉體。
總太陽輻射截獲由地球，達到約1 ％的地球表面，而且大部分是反映然後再波長的紅外輻射。由於這旅行回來的紅外輻射，通過對低層大氣的空間，它遇到的溫室氣體，如水蒸氣，二氧化碳，甲烷，氧化亞氮和臭氧。它起因這些氣體分子的振動和釋放的紅外輻射，甚至更長的波長。氣體分子的振動則具有較高的動能，這有助於熱烈低層大氣和地球表面。如果沒有這種自然溫室效應，地球將太冷支持formsof生活，我們今天在這裏找到。
Human activities add greenhouse gases to the atmosphere. For example, burning carbon-containing fuels such as coal, gasoline, and natural gas releases huge amounts of carbon dioxide (CO2) into the atmosphere. Growing crops and raising livestock release large amounts of methane (CH4) and nitrous oxide (N2O). There is
considerable and growing evidence that these inputs are increasing the natural greenhouse effect and warming the earth’s atmosphere and surface-something often referred to as human-enhanced global warming. We discuss this at length in Chapter 16.
人類活動購買溫室氣體排放到大氣中。例如，燃燒含碳燃料，如煤炭，汽油，天然氣排放大量的二氧化碳（ CO2 ）到大氣中。種植作物和飼養牲畜釋放大量的甲烷（ CH4 ）和氧化亞氮（ N2O ） 。有相當多和越來越多的證據表明，這些投入是不斷增加的自然溫室效應和氣候變暖對地球大氣層和表面的東西通常被稱為人類增強全球變暖。我們討論這個問題終於在第16章。