I wanted to hark back to the global warming and thermal expansion of water topic on approx. the first screen's worth of comments. Thermal expansion is *huge*. Eg this from WorldWatch: 20% of the rise in sea levels is melting ice, the rest is thermal expansion. Over the past century, global sea levels have risen an estimated 10 to 25 centimeters (4 to 10 inches). So 8-20 centimeters of the rise is due only to bigger atoms of water, not more of them. It's exactly the same process as the thermal expansion of air, such as lifts hot air balloons, but we're not used to thinking about water in those terms because its coefficient of expansion is so tiny. That means on the scale of a pot of water, it's indetectable. On the scale of an ocean, it can flood Bombay.
Aside to the person asking about snowflakes: there's a marvelous site with stunning snowflake photos by Libbrecht, a researcher on snowflakes, and others. There's much more info about snowflakes there, too.
Finally: re synching menstrual cycles: yes, it's hormones, but how does female A know what female B's hormones are up to? Apparently that's communicated by pheromones or some sort of molecules that affect the olfactory system, but without any conscious perception of odor. |
