Website of the Week: Science Buddies

It's that time of the year again ... time to knuckle down and select a topic for your science fair project. Or maybe you already have an idea but you just need some help to put it into practice. Whatever your status, Science Buddies is for you. With over 700 science fair project ideas -- broken down into categories like Chemistry, Microbiology, and Sociology -- you're sure to find a topic to interest you. Following the advice of the Science Fair Project Guide will keep your experiment on track. The Ask An Expert "online bulletin board [is] staffed by volunteer scientists and top high school students" who are ready and willing to help you should you get stuck. And before you cart your project off to the competition, be sure to read Amber Hess' Science Fair Tips for Success on the Science Competitions page.

Good luck, everyone! :)

Thoughts on Blog Carnivals

I've recently learned about blog carnivals, these online magazine-like publications organized and hosted by different blogs. Each blog carnival features posts from various blogs on a specific topic with new issues posted on a regular basis. The range of blog carnival topics is wide, with Blog Carnival listing over 4,000 different ones, on themes ranging from kidney stones to signing babies and everything in between.

I've been having fun submitting Mama Joules' posts to different blog carnivals. I haven't quite found our exact niche -- I'm still looking for a "family science blog carnival" -- but I've enjoyed being a part of these issues:

Tangled Bank #107. Science. Love this issue's "choose your own" theme.

June 2008 issue of Learning in the Great Outdoors. Environmental education. Good stuff!

Carnival of Mathematics #34. All things math.

Berry Go Round #5. A celebration of plants.

How big are raindrops?

Photo credit: Leon Brooks, BurningWell.org

While I was taking out the trash the other night, I commented to my young son that it was misting outside.

He gave me a funny look and said, “It’s raining.”

I said, “No, it’s misting. It’s not coming down hard enough to be rain.” I started to tell him about the different ways that people might describe rain, like drizzle or light showers, but I stopped short.

How do we define rain? What are the actual meteorological classifications of liquid precipitation? I thought that this would be a simple question, but there's been some debate on the subject.

According to the National Oceanic and Atmospheric Association, drizzle consists of fine water droplets with diameters of less than 0.5 mm; rain is usually larger than 0.5 mm. Fog droplets are similar to drizzle, but they don’t hit the ground.

I found an older set of definitions from the U.S. Department of Agriculture, though the U.S. Geological Survey at The Water Cycle: Precipitation. The 1959 USDA table referenced on this site has definitions for precipitation that include fog, mist, drizzle, light rain, moderate rain, heavy rain, and cloudburst. Part of this table included the median diameters of different precipitation droplets, including 0.96 mm for drizzle and 1.24 mm on up for rain (note that these don't exactly match the NOAA definitions).

I couldn’t wrap my mind around the numbers, so I took the data about droplet sizes and made my own graph. I discovered a couple of interesting things when I sat down with the numbers.

Data taken from a USGS adaptation (The Water Cycle: Precipitation) of Lull, H.W., 1959, Soil Compaction on Forest and Range Lands, U.S. Dept. of Agriculture, Forestry Service, Misc. Publication No.768
First, none of the droplets are very big. Even the largest water droplet -- occurring during a cloudburst -- is extremely small, typically measuring less than 2/10 of an inch in diameter. (Now, I don’t know about you, but I’ve had raindrops fall in my eye and it’s hard for me to believe that they are usually so tiny.)

Second, comparing droplet sizes reveals enormous differences between the categories. Cloudburst droplets (at 2.85 mm in diameter) are over 200 times larger than fog droplets (0.01 mm in diameter).

How do scientists know these things? Here’s one way: In 1971, researcher Motoi Kumai went out into the fog armed with gelatin-coated glass slides and studied the results under an optical microscope. He measured the radii of about 20,000 fog droplets for his paper, published in the Journal of Atmospheric Sciences in 1973. (You can read Arctic Fog Droplet Size Distribution and Its Effect on Light Attenuation in the online journals at the American Meteorological Society. Interesting side note: Kumai found that long-lasting fogs have larger water droplets than short duration fogs.

So, how big are raindrops, anyway? See for yourself! The next time you see a storm brewing, take a piece of colored construction paper outside and lay it securely on the ground. Let the first few raindrops fall and then grab your paper and quickly run inside before you both get drenched. The water droplets should have made marks on your paper; you can take your own measurements. Do you think that your results will be the same or different than those found by the meteorologists? Why?

Nature Blog Network

I recently discovered Nature Blog Network, which bills itself as "a resource for the very best nature blogs on the net." You can sort through member blogs by topic, such as ecosystem (that's where I put Mama Joules), marine, birds (a very popular topic, I learned), mammals, mollusks (three snail blogs at the time of this writing), and flora (plants & trees).

I'm still picking my way through the listings, but I have a couple of early favorites. Ugly Overload is a nice compliment to Mama Joules' Weird Animal Names. Ugly Overload is just what it says -- a website for strikingly ugly animals (with great pictures). According to their website, Ugly Overload is for "giving ugly animals their day in the sun." Check out the entry from May 22, 2008 on Insects and Friends about giant live beetles found unexpectedly in a package at the post office!

I also liked the photographs at tHE tiDE cHAsER, especially the close-ups of sea life. And be sure to check out Bill of the Birds and his giant Goudasaurus!

NOAA Photo Library

I was floating around the Internet yesterday and found a wonderful cache of photographs currently held by the National Oceanic and Atmospheric Administration. These pictures, which are now part of the public domain, can be found at NOAA Photo Library. According to the website, you are allowed to use these pictures, as long as you give credit back to NOAA or their affiliates. (Check About the Images for more information.)

So, what sort of pictures do they have? How about these?


A Coral Reef in the Florida KeysPhoto credit: Florida Keys National Marine Sanctuary


A Snowflake Photograph taken by Wilson "Snowflake" BentleyPhoto credit: NOAA


An Intense Cloud to Ground Lightning Strike
Photo credit: NOAA Photo Library, NOAA Central Library; OAR/ERL/National Severe Storms Laboratory (NSSL)

Enjoy!

Drought for thought

Photo credit: Jon Sullivan
When I was in graduate school, we spent some time discussing natural disasters and their impacts on humanity. I was surprised to learn that drought was considered to be a significant natural disaster. In the United States, yearly drought-related costs are higher (on average) than flood and hurricane-incurred costs combined. (source: Drought for Kids: Comparison of Droughts, Hurricanes and Floods by the National Drought Mitigation Center of the University of Nebraska-Lincoln)

What is drought? Simply put, a drought occurs when there is a substantial lack of rainfall in a given area, enough to negatively impact people, plants, and animals.

The definition of drought, however, is unique to a given location. What would be considered a drought in the wetlands of southern Florida, for example, would be considered an abundance of rainfall in the United States’ desert southwest.

There are a couple of factors that make coping with drought challenging. For one, by the time that you realize you are in drought, it’s already begun. Pinpointing when a drought first starts is nearly impossible, although groups like the United States Geological Survey do an admirable job of searching for signs of trouble. (Among other things, the USGS monitors the flow of water in streams and rivers. Low flow signals a possible drought-related problem.)

Once you realize that you are in a drought, no one can say how long it will last. Rainfall models can only tell you so much. For city planners and others who regulate water flow, it can be difficult to decide when and how to moderate water intake. Imposing water restrictions, ironically, can make a drought situation worse if panic ensues and people begin to hoard water. UNL’s National Drought Mitigation Center describes the challenge of managing drought as "The Hydro-Illogical Cycle".

In the United States, the U.S. Drought Monitor keeps track of drought conditions. One place to check on world-wide drought situations is NASA’s Earth Observatory Natural Hazards: Crops & Drought.

Website of the Week: KIDZONE

The St. Louis Public Library has put together a wonderful and comprehensive set of links for kids as part of their online science lab, KIDZONE. There are over 100 links on this page, connecting you to everything from the Periodic Table of Comic Books to The yuckiest site on the internet. Let me know which links you like best!

Website of the Week: The Bailey-Matthews Shell Museum

If you are planning a trip to southwest Florida, be sure to stop by The Bailey-Matthews Shell Museum. They have a lovely and extensive online photographic selection of Southwest Florida Shells. Or, if you'd rather print your own poster of 65 species of Southwest Florida shells, check out this pdf file of Seashells of Sanibel and Captiva Islands. You can also print a dot-to-dot coloring page and a word search from their page of Kids' Stuff or purchase a School Shell Collection Kit. And if you are going to be in the Lee County, Florida area, be sure to print out a FREE Child Admission Coupon for kids ages 10 and under.

(My thanks to Mom for sharing her find with us! Love you, Mom.)

Website of the Week: Ask-A-Scientist

This week’s Website of the Week is Ask-A-Scientist, operated by the Division of Educational Programs at Argonne National Laboratory. This educational outreach program – now in its 17^th year! -- is designed for students and teachers in grades K-12. Have a question about science that you just can’t find an answer to anywhere else on the web? This is a good place to post it. Previous answers are indexed under categories such as astronomy, materials science, veterinary, and weather. Want to learn about Cow Magnets? Why Boiled Eggs Turn Solid? Why people sometimes have Red Eyes in Photographs? These answers, and more, are waiting for you in the Ask-A-Scientist questions and answers archive.

Website of the Week: Snow Crystals

In my part of the world, the weather is finally starting to look like winter. My boys and I have been anxiously watching The Weather Channel, hoping for a snowy forecast.

So, this week’s tip of the hat goes to Snow Crystals, a website devoted to the beauty and science of snowflakes. Learn the physics behind snowflake formation, see how to preserve a snowflake, and check out the beautiful pictures in the photo gallery.

A nod also goes to the American Library Association, for pointing me to this great website through their aptly named listing of Great Websites for Kids.

Website of the Week: Ology

Check out the American Museum of Natural History's Ology website!

The suffix "ology" means "the study of." And you can study lots of cool science topics on this website, including ornithology (the study of birds) and ichthyology (the study of fish). Meet a volcanologist (a scientist who studies volcanoes), design a model coral reef, or cook your very own set of "cosmic cookies."