11.   Climate experts say the increased frequency of extreme events is exactly what computer models have been predicting will happen as the Earth warms.

12.   Even so, the good correlation between his work and other recent reconstructions of past climates prompted a variety of climate experts to say the study was valid.

13.   Eventually, laboratory work and observations should narrow that range, many climate experts say, but uncertainty will always remain.

14.   Looking ahead, climate experts said an important part of any rebuilding of Afghanistan would be prompt re-establishment of basic, regular measurements of precipitation and other weather conditions.

15.   Most climate experts are certain that global warming is real and that it threatens ecology and human prosperity, and a growing number say it is well under way.

16.   Most climate experts expect La Nina to begin breaking up soon.

17.   Other climate experts echoed that caution but said it did not doom earthshine as a novel way of peering back at Earth.

18.   The climate experts on the panel believe their models have become increasingly reliable.

19.   The specialist, Robert T. Watson, chief scientist of the World Bank, is highly regarded as an atmospheric chemist by many climate experts.

20.   The specialist, Dr. Robert T. Watson, chief scientist of the World Bank, is highly regarded as an atmospheric chemist by many climate experts.