百葉箱 (hyakuyōsō or hyakuyōbako: louvered box for housing meteorological gauges outdoors) 100 + counter for flat things + box
This compound refers to a boxed gauge that has traditionally been a fixture in the Japanese schoolyard (校庭, kōtei: schoolyard, school + courtyard). A typical 百葉箱 includes a thermometer, a humidometer, and a pressure gauge. This collection of gauges is ordinary, not remotely high-tech.
But if you want to jump up several levels to the forefront of meteorological research, you can learn about the boxed outdoor meteorological gauges that the pros use. My friend Laura Peticolas works with gauges called magnetometers at the Space Sciences Lab in Berkeley, California. Magnetometers measure magnetic fields, thereby helping scientists study auroral substorms. A substorm is an eruption of energy in Earth’s magnetic field that causes brilliant, dancing auroras (Northern and Southern Lights). What’s more, a Japanese scientist (Shun-ichi Akasofu) started the whole study of substorms! Maybe his interest grew out of the 百葉箱 in his schoolyard!
Here’s a little more information about auroral substorms and about the Berkeley lab’s magnetometer project:
