Thunderbolts and Lightning, Very Very Frightening Me!

Summer is here, the time of lazy days, high heat, fireflies, and of course, thunderstorms. Thunderstorms can happen anywhere at any time, but are most likely to happen when it gets hot. Here in the east where I live, my thunderstorms are most frequently in the late afternoon. In the Midwest, they usually happen in the evening or overnight. Where do these storms come from?

There are two ways for a thunderstorm to form that I’ve noticed. The first is associated with a cold front. Usually, what I’ve seen is we’ll be in a heat wave (three or more days of temperatures above 90̊) and when a cold front comes in to cool things off a bit, the contrast between very hot and less hot air causes enough atmospheric instability that severe thunderstorms form all along the front.

Afternoon thunderstorm building over Pennsylvania

The other situation, and this is my favorite, is what I call the pop-up storm. These happen later in the day and form when the heat and humidity of the day force hot air to rise. As the air rises it cools and condenses into clouds. If the cloud gets tall enough, the water vapor molecules eventually for ice crystals. If the ice crystals collide with each other, they can create an electrical charge. The electrical charge is lightning. A bolt of lightning is hotter than the surface of the sun and causes the air around it to superheat. The rumble of thunder you hear is the sound of superheated air expanding.

Anvil cloud from a dissipating thunderstorm

Lightning is lazy. When cloud-to-ground lightning strikes, it looks for the shortest and easiest path to the ground. That means the tallest object around. Being in a flat, open area (such as a beach, the rim of the Grand Canyon) or on a prominence such as a hill or mountain makes you a target. Avoid those areas. Also, stay away from tall objects like trees. Get out of the water when you hear thunder. A good rule of thumb is if you can hear thunder, the lightning is close enough to hit you. Pretty much anything indoors is a safe place to hide from lightning, as long as it’s not made completely out of metal.

Lightning strikes near Crater Lake

Another way for thunderstorms to kill you is with a flash flood. Don’t try to drive through water on a roadway. Listen for a rushing sound if you’re hiking in a canyon and move to higher ground. Even if it’s not raining where you are, a flood from rain upstream will find you so be aware of local weather conditions.

A pair of storms approaches in Wyoming

Hail sometimes accompanies a thunderstorm. While it can be cool to see everything covered in ice during the summer, large hailstones can cause property, crop, and people damage. An umbrella won’t protect you from a frozen baseball that’s been falling for thousands of feet so get inside. Also, hail is an indicator of possible tornadoes. Refer back to this post from March.

Odds are pretty good you’ll survive the next thunderstorm. Take the time to relax by listening to the sounds of the rain and thunder. Appreciate all the complexities and nuances that go into making nature’s rumbly light show.

This week's information comes via the National Severe Storms Laboratory All photos are my own.

Species of the Month

This month’s species of the month is the state flower of California, the California poppy. This flower is not found exclusively in California. It brightens roadsides all along the west coast. Its sunny orange color makes me think of summer sun, a fitting match for the first day of summer.

Scientific name: Eschscholzia californica

Kingdom: Plantae (plants)

Class:   Magnoliopsida (dicotelydons)

Order: Ranunculales (flowering basal eudicots)

Range: Baja California north to Washington, east from southern California to El Paso

Habitat: open areas with well-drained soil, grasslands, oak savannahs, deserts

Lifespan: may be annual or perennial, depending on local climate

Diet: sunlight and water

Predators: hoverflies, beetles

Conservation Status: no special protection

Other Information: A familiar sight along roadways in the far west. California poppies close their flowers at night and on cloudy days. These sunny flowers love sun! Flowers have four petals of bright orange to light yellow. It enjoys disturbed areas. Poppies growing in a mild winter climate are perennials and will grow back for several years. In cold winter climates, they are annuals and grow from seed every year.

This week's information comes from USDA, another USDA site, and US Forest Service. Pictures are from USDA.

Road Trip Adventure- Behind the Scenes

Last week I shared pictures, video, and information about the horseshoe crab. This week we take a behind the scenes look at the adventure. While the trip to Delaware wasn’t as tedious as a National Geographic photo shoot (they might spend three months to get that one shot you see in the magazine), it wasn’t the figurative walk on the beach that it literally appeared to be.

Welcome to the second smallest state!
(Delaware Business Times)

The biggest question mark I had to deal with was weather. The forecast was for thunderstorms. Fortunately my daughter and I dodged those. I wasn’t about to head to the beach during a thunderstorm. Your happiness, gentle reader, is not worth my life. It was cloudy that night, and I wasn’t sure if it was the moon itself or just the tides associated with the moon that draws the crabs to the beach. Apparently, it’s the tides and not moonlight. 

Rain was our closest companion during the weekend. I was hoping to get daylight shots at noon’s high tide the Saturday we were there. However, threatening clouds were on the horizon and with more thunderstorms in the forecast I decided to bag it. We managed to get another trip to the beach at low tide, where a few stragglers were going back out to sea. There were also a few dead crabs below the wrack line, some birds, and a shopping bag full of garbage. Saturday night rain kept me awake and at some point during the night the tent decided it was too wet to hold the water back any longer.

And they were right (Pintrest)

Camping in the rain can be a miserable experience, but our second closest companion, at least while we were in camp, was the mosquitoes. They helped me set up the tent by encouraging me to do it faster. They even managed to get inside. They got in the car. They visited me in the bathroom. They were undaunted by the rain. I learned how foolish I was to believe that they lost their taste for me over the years. East Coast mosquitoes will surely beat West Coast mosquitoes in a street fight any day.

Business was booming at the 24 hour buffet
(End Times News)

With rain, you are sure to have humidity. My hair is too short to get frizzy, but that wouldn’t bother me. The bother was driving into camp, to the beach, and back to camp without being able to see anything. Nothing I did could stop the humidity from fogging up the windshield. If it wasn’t the foggy windshield on Friday night it was the actually foggy fog. How humid was it? I had a box of graham crackers (we had raw smores because of the rain) stored in my cooler (no ice) and the cardboard still managed to get soggy, despite the outside (and inside) of the cooler staying out of the rain. I’ve never seen humidity like it.

All this complaining is to remind you that fieldwork has its discomforts. Even though all I did this time was observation, we do this in all conditions. Always keeping safety in mind, research and fieldwork go on despite nasty weather. Obviously, sometimes conditions make it impossible to get the job done. I can’t count frog eggs in the rain because the surface ripples make it impossible to see any eggs below. I won’t be pulling invasive weeds when there’s a foot of snow on the ground. Sometimes conditions interfere with natural processes we’re trying to observe. Insects won’t be around much on a windy day. A cool, cloudy day will keep reptiles away. So we wait. And that’s why your National Geographic picture is three months in the making.

Road Trip Adventure- The Crabs of Delaware

The horseshoe crab is possibly the most bizarre critter you will encounter on a sandy Atlantic beach. Resembling a helmet with legs and a tail, they are not actually crabs at all, but are more closely related to spiders. They are nearing the end of their spawning season, and I traveled to Delaware to get some time in the field and see for myself.

Horseshoe crab (left) and traditional  Dungeness crab (right)
side by side for comparison

Horseshoe crab undercarriage

These marine arachnids are an ancient species dating back over 300 million years. I’m sure they’ve been spawning since then, but unlike most sea creatures, they come ashore to lay and fertilize eggs. Mid-May to early June is prime time for spawning. The crabs haul ashore at high tide and they prefer full or new moons. I just happened to arrive a day after full moon, so the event was in full swing when I got there. Check the video raw here. 

Horseshoe crabs spawning at midnight

Males are smaller than females, and will climb on the backs of females to fertilize the eggs as they are released. There are more males than females, so sometimes there will be one or two “satellite males” clinging to the sides in addition to the first male to attach. Females lay a few thousand eggs per shot, and will emerge to spawn several times over the course of the season.

She’s laying that many eggs for good reason: there are tons of migratory and seasonal shorebirds on the coast looking for a quick and easy meal. Eggs and freshly hatched larva really hit the spot. Eggs hatch after two to four weeks. Larva hang out in the shallow water for a few years, while the adults return to the briny deep.

Horseshoe crab returning to sea

Walking the beach the day after watching the midnight spawning, there were a few stragglers. In some cases, all that remained were the crab tracks. The shell plows a path in the sand that ends in a horseshoe shaped depression (or a crab, if it hasn’t made it back to sea yet), which is how the crab got its name. There were also a few dead ones that were stranded after the tide went out. 

Leaving behind a crab track

Seeing a live horseshoe crab for the first time was an interesting experience. I’m not a diver so my only in-person encounters with marine life has been tidepool critters that don’t move, such as a sea anemone. Getting down to the beach and turning on a flashlight and seeing all those crabs together in a writhing, tumbling mass of helmets was incredible. If you ever get the chance to watch, I highly recommend it. Just remember to leave no trace. I picked up about 2 ½ gallons of garbage before leaving.

Nature Minute now has a Youtube channel! I will add videos as I feel like making them. In addition to the video linked above, there are others from my weekend adventure in Delaware. Next week I'll have some stories from the road.