Although blogs like Pink Tentacle have been reporting the tadpole rains of Japan for over a week now, the news is finally hitting mainstream outlets. Apparently small fish as well as tadpoles are falling on various districts in Japan. Usually they're dead by the time they hit the ground. One man claimed he found 13 tiny carp had rained onto his car. Nobody has come forward with a good theory about how they have gotten into rain clouds, nor has anyone been able to explain what might have changed recently to make this happen.

According to the UK Guardian:

One popular theory is that the creatures were sucked up by waterspouts but meteorologists say no strong winds have been reported in the areas where tadpoles were found. One expert said gusts too weak to be picked up by observatories might have sucked up small quantities of water, along with a few unfortunate tadpoles. Ornithologists said it was too early too rule out their feathered friends.

Kimimasa Tokikuni, head of the Ishikawa branch of the Japanese Society for the Preservation of Birds, told the Yomiuri Shimbun that bigger birds, such as herons and black-tailed gulls, might have dropped the tadpoles after being disturbed in mid-flight.

But the startled bird theory fails to answer a simple question: why haven't the "flying" tadpoles been noticed before?

Less unusual but no less alarming have been this spate of mega-hail storms in China recently. Giant hail stones, combined with winds up to 62 miles per hour, crushed thousands of houses and injured hundreds of people over the last week. Xenophilia reports:

Recovery efforts have begun in eastern China following a severe hail storm on Sunday that killed at least 14 people and destroyed thousands of homes.

Hail stones and winds of more than 100km/h (62mph) lashed the province for nearly 90 minutes, uprooting trees and scattering debris across roads.

The Civil Affairs bureau in Anhui province says more than 10,000 people had to be taken to emergency shelters.

I suppose you could call this climate change, since in fact it does represent a change in the climate. Especially the tadpoles. But I have to admit it seems like something a lot weirder than that.

Winds blowing into and out of the 7-km deep crater create "Rossby waves," which in turn affect other weather systems. According to PhysOrg:

These waves reroute the high altitude winds on Mars and force the weather system towards the south pole. In the western hemisphere of Mars, this creates a strong low-pressure system near the south pole, and a high-pressure system in the eastern hemisphere, again near the south pole.

The temperatures in these two systems are different. The low-pressure system is the right temperature to cause carbon dioxide snow, which turns into ground frost. In the high-pressure system there's no snow. So you get ground frost without a snow covering. That means the ice cap is actually half frost, and half carbon dioxide snowy frost. The areas covered in snow don't melt off in summer because they reflect the sunlight. But frost grains can't reflect sunlight as well, and their shape actually exposes them to more sunlight. Which means they're easily melted in summer.

So that irregular polar cap you're seeing is the result of two winter different weather fronts coming together — one full of snow, the other causing frost. And in summer, only one side melts away — the non-snowy side. Which means there's always good carbon dioxide skiing on the western side of the Martian south pole, even in summer. Composite image via ESA/ Image Courtesy of F. Altieri (IFSI-INAF) and the OMEGA team.

Mars Polar Cap Mystery Solved [via PhysOrg]