91色情片

The discovery that the ozone hole over Antarctica is bigger than ever this
year has confounded theories that its size peaked by 1998, says Jonathan
Shanklin of the British Antarctic Survey in Cambridge. The hole, which is
created each southern spring by artificial ozone-destroying compounds, is more
than three times the size of the continental US. Industrialised countries have
reduced their emissions of these chemicals in the 15 years since the discovery
of the hole. But, says Shanklin, the ozone鈥檚 recovery has been delayed by global
warming and China鈥檚 drastic increase in emissions in the late 1990s.