Stuart Butchart said that, since 2002, the risk of species extinction has actually increased, not decreased, and the need to increase the scale of our efforts.
He's is working on more sensitive seismometers using fiber optics. The information that scientists gather helps them create pictures of what's inside the Earth.
If forecasts of weather just days away are often wrong, how can scientists claim to know what climate will be like 50 years out? Vicky Pope responds to critics of computer modeling.
Stefan Maus and the magnetic north. Does a magnetic compass point to the North Pole? The answer is not exactly. The direction to magnetic north always changes.