From the 1968 film “Ice Station Zebra”.
Kelgarries wanted the job done in a month, but he was a soldier, not an engineer. The construction and precision placement of twin temporal gates, one at the highest point on Vila do Porto, one of the smaller islands of the Azores, and the other at the epicenter of the Tunguska Event, some 65 kilometers north-northwest of the town of Vanavara, could not be rushed, particularly at the stage of configuring the fusion generator for each and then applying power to the gates.
Both gates had to be absolutely synchronized in power output and frequency for their plan to work.
The plan? To intercept an experimental alien space and time craft that launched nearly 4,000 years ago from what used to be the main island in the Atlantis chain, where now remains only the tiny islands of the Azores, and due to explode in the atmosphere above a remote portion of Siberia on June 30, 1908. The field the gates would generate between the launch and crash points would create a nexus in the time stream intersecting with the ship and sending it off source to another place in the far distant past.
Found at The Verge
From space, the Earth looked very different from what modern humans would expect today. For one thing, the Panama isthmus did not connect North and South America, allowing direct low-latitude circulation between the Atlantic and Pacific Oceans. There was no Drake Passage separating South America from Antarctica and the Arctic was also more restricted.
It came from space. The object, impacting on or near the coast of what is now called New Jersey. There was an abrupt release of carbon into the atmosphere causing global climate warming at an accelerated rate. It took decades or centuries, not thousands or tens of thousands of years for the planetary temperature to rise 5 to 9 degrees Centigrade or about 9 to 16 degrees Fahrenheit.
Numerous single-celled ocean bottom organisms became extinct while other surface species moved to the poles in order to survive.
Overall, the climate became wetter, Arctic freshwater concentrations increased, and although there was a general lack of global ice, sea levels still rose due to thermal expansion.
“Dr. Barnes, you’re not saying that this impact over 55 million years ago caused modern climate change. That’s not what you explained to me before.”
“Of course not, Colonel. However it is necessary to…”