While the world's politicians argue in Copenhagen, some scientists are speaking out at an alternative "skeptics' conference."

More than 50 scientists, businessmen and lobby groups met to discuss alternative theories about global warming and climate change, reports the Telegraph. The paper highlights a few scientists, including Professor Henrik Svensmark, a physicist at the Danish National Space Center in Copenhagen, who said the recent warming period was caused by solar activity.

Svensmark said that the last time the world experienced such high temperatures, during the medieval warming period, the Sun and the Earth were in a similar cycle.

Professor Nils-Axel Morner, a geologist from Stockholm University, said sea-level rise has also been exaggerated by the "climate alarmists" using computer models.

He said observational data from lake sediments, coast lines and trees show sea levels have remained stable.

Read the full story at the Telegraph.