| 单词 | ozone levels |
| 释义 | ozone levels We also found that park visits fall on high ozone days – especially during summer and fall, when peak ozone levels typically occur. Retrieved from Wikipedia CC BY-SA 3.0 By the year 2000, ozone levels in national parks were, on average, very similar to those in metropolitan areas. Retrieved from Wikipedia CC BY-SA 3.0 This response was most pronounced during summer and fall, when both visitation and average ozone levels are highest. Retrieved from Wikipedia CC BY-SA 3.0 They discovered that the ozone levels had dropped by 40 per cent over 30 years. Times, Sunday Times Since the early 2000s, ozone levels in both national parks and metropolitan areas have improved. Retrieved from Wikipedia CC BY-SA 3.0 |
| 随便看 |
英语词典包含147115条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。