Giant tsunamis, super volcanoes and earthquakes could pose a greater threat than terrorism, scientists claim.

Global Geophysical Events, or "Gee Gee's", as they are nick-named, are not being taken seriously enough, they say.

The global community needs to monitor these risks, and develop strategies to cope in the face of a catastrophe.

However, we are making good progress in reducing the threat of asteroid impacts, the researchers said during a briefing at the Royal Institution, UK.

Battening down

Since 9/11 we have become acutely aware of the threat of terrorism. Governments worldwide are battening down the hatches and ratcheting up the security.

But, in terms of grave threats, are we really looking in the right direction?

Giant walls of water that can devastate coastal cities, volcanoes so big that their ash crushes houses 1,500km (932 miles) away, giant earthquakes and asteroid impacts. These are very rare events and, if we are lucky, nothing like them will happen in our lifetimes.

But in the longer term, Gee Gee's may be our undoing if we do not take action. According to researchers, careful preparation could potentially save thousands of lives.

In the first few hours after a giant asteroid crashed into the coast of Mexico nearly 65 million years ago, the Earth's atmosphere became so hot that it quickly incinerated any unprotected life on land, according to a new report by a team of American geophysicists and geologists.

A massive gamma-ray burst could have helped destroy much of life on Earth 440 million years ago, say a team of U.S. scientists.

Professor Adrian Melott of the University of Kansas and team argued their case in a paper accepted for publication in the International Journal of Astrobiology.

They are out there, ready to smack into the Earth and wipe out human civilization, but astronomers said on Wednesday they are well on their way to finding every asteroid that poses a threat.

The next task will be to look for smaller objects that might just destroy, say, a city, the experts told the U.S. Senate's Subcommittee on Science, Technology and Space.

In an update on the Near Earth Object Observation Program, experts told the Senate subcommittee that they are on schedule to finding everything bigger than 1 kilometer in diameter that might approach the planet.

"The survey officially started in 1998 and to date more than 700 objects of an estimated population of about 1,100 have been discovered, so the effort is now believed to be over 70 percent complete and well on the way to meeting its objective by 2008," NASA's Lindley Johnson told the hearing.

Next time an asteroid or comet is on a collision course with Earth you can go to a web site to find out if you have time to finish lunch or need to jump in the car and DRIVE.

University of Arizona scientists are launching an easy-to-use, web-based program that tells you how the collision will affect your spot on the globe by calculating several environmental consequences of its impact.

The hunt for space rocks on a collision course with Earth has so far been pretty much limited to the Northern Hemisphere. But last week astronomers took the search for Earth-threatening asteroids to southern skies.

Astronomers using a refurbished telescope at the Australian National University's Siding Spring Observatory discovered their first two near-Earth asteroids (NEAs) on March 29. NEAs are asteroids that pass near the Earth and may pose a threat of collision.

A 100-foot diameter asteroid will pass within 26,500 miles of Earth on Thursday, the closest-ever brush on record by a space rock, NASA astronomers said Wednesday.

The Planetary Defense Conference (Protecting the Earth from Asteroids) was held 23-26 February 2004 in Garden Grove, Orange County, California. The conference was sponsored by the AIAA (American Institute of Aeronautics and Astronautics) and the Aerospace Corporation, with 120 persons attending. The Chair was William Ailor and Technical Chair David Lynch, both of Aerospace Corp.

Scientists at Cardiff University, UK, believe they have discovered the cause of crop failures and summer frosts some 1,500 years ago – a comet colliding with Earth. The team has been studying evidence from tree rings, which suggests that the Earth underwent a series of very cold summers around 536-540 AD, indicating an effect rather like a nuclear winter.

The scientists in the School of Physics and Astronomy believe this was caused by a comet hitting the earth and exploding in the upper atmosphere. The debris from this giant explosion was such that it enveloped the earth in soot and ash, blocking out the sunlight and causing the very cold weather.

On New Zealand's South Island, according to Wollongong University geologist Edward Bryant, are several Maori legends that allude to unimaginable catastrophe. Tales about the falling of the sky, raging winds, fire-storms from space, massive waves and floods. Tales of how the moa, the emu-like New Zealand flightless bird, was killed off by the man/god Tamaatea, who set fire to the land by dropping embers from the sky.

There are more than just stories. Near the town of Tapanui are the remains of fallen trees, spread over dozens of kilometres but pointing in the same direction, as if felled by a massive air-burst. Then there are the place names: Tapanui itself, which means "the big explosion", and the common affixes of ka and tai, which mean fire and wave.

Impact cratering is now recognized as a major geological process on Earth. In particular, giant impacts had a fundamental influence on the geological and biological evolution of our planet with possible climatic effects. There are more than 160 confirmed impact craters on Earth, among which 17 are located in Africa, but it is estimated that only 10% of impact craters larger than 10km and younger than 100Ma are known.

The Sahara is a particularly favorable region to host young impact craters, but according to cratering rate estimates, most of them still remain to be discovered, hidden under dry sandy sediments. Only four confirmed impact craters are currently known in eastern Sahara.

One of the great advantages of being short-lived by geological standards is that life seems relatively stable to us. In the span of time that we humans have been fully ourselves as a species — the oldest human fossils are only 160,000 years old — life on this planet has gone on essentially uninterrupted, no matter how cataclysmic our own history has been. We live in the midst of one of the great extinctions, largely caused by humans, and yet we've experienced nothing like the meteor that crashed into the earth 65 million years ago and destroyed the dinosaurs.

One of the most powerful gamma ray bursts ever - and one of the closest seen to date - has been pinpointed by two Australian astronomers who continue to watch the spectacular event unfold.

Doctoral student Paul Price and a colleague, Dr Bruce Peterson, both from Canberra's Australian National University, pinned down the cosmic explosion late on Saturday night following an electronic tip-off from a satellite launched by the U.S. space agency, NASA.