Stories tagged Earth and Space Science

Sep
20
2011

There’s been some buzz about the relationship between clouds and climate recently, prompting Andrew Revkin of the New York Times’ Dot Earth blog to get his panties in a twist about the “…over-interpretation of a couple of [scientific] papers…”

What gives? I wanted to know too, so I’ve done a bit – ok, a lot – of research and this is what I can tell you: The heart of the discussion is not whether there is a cloud-climate connection (that’s clear), but rather over what that relationship behaves like. There are at least three possible theories, but before we get to those, let’s review some important background concepts.

Gimme the Basics First

Cloud Formation

First, scientists think of air as units of volume called air masses. Each air mass is identified by its temperature and moisture content. Clouds are basically wet air masses that form when rising air masses expand and cool, causing the moisture in the air to condense. You can see the process in action yourself just by exhaling outside on a cool morning. The Center for Multiscale Modeling of Atmospheric Processes has a webpage to answer your other questions about clouds.

Earth’s Energy Budget
Earth's energy budget: Incoming solar energy is either absorbed (orange) or reflected (yellow).  Outgoing energy is radiated (red).  The arrows show the direction and magnitude of movement where thick arrows signify bigger movements.
Earth's energy budget: Incoming solar energy is either absorbed (orange) or reflected (yellow). Outgoing energy is radiated (red). The arrows show the direction and magnitude of movement where thick arrows signify bigger movements.Courtesy NASA

Energy from the Sun is essential for life on Earth. Let’s pretend the Earth has an “energy budget” where solar energy is like money, absorption is like a deposit, reflection is like a transfer, and radiation is like a withdrawal. It’s not a perfect analogy, but it’ll work for starters: Most of the incoming solar energy (money) is absorbed by (deposited into) the ocean and earth surface, but some is absorbed or reflected (transferred) by the atmosphere and clouds. Most of the outgoing energy is radiated (withdrawn) to space from the atmosphere and clouds. The figure to the right illustrates this process.

The Greenhouse Effect

Thanks to the greenhouse effect, our planet is warm enough to live on. The greenhouse effect occurs within the earth’s energy budget when some of the heat radiating (withdrawing… remember our budget analogy from above?) from the ocean and earth surface is reflected (transferred) back to Earth by greenhouse gases in the atmosphere. Greenhouse gases include carbon dioxide, methane, and water vapor. This National Geographic interactive website entertains the concept.

Climate Change

Climate change is occurring largely because humans are adding more greenhouse gases to the atmosphere. More greenhouse gases in the atmosphere means more heat reflected back to earth and warmer temperatures. Warmer temperatures might sound pretty good to your right now (especially if you live in Minnesota and could see your breath this morning as you walked to school or work), but it’s not. Why? Check out NASA’s really great website on the effects of climate change.

Alright, already. What’s the climate-cloud relationship?

From what I can tell, there are three possible theories about the climate-cloud relationship:

  • Clouds actively drive climate change. This is a linear process where clouds reflect too much heat back to Earth, which increases the average global temperature and causes climate change.
  • Clouds passively blunt climate change. This is a cyclical process where more climate change includes increasing average global temperature, which increases average global evaporation, which creates more clouds. More clouds absorb more heat, keeping the average global temperature from rising even faster and lessening climate change. This slows down (note: it does not stop) the rate of climate change.
  • Clouds passively amplify climate change. This is a cyclical process where more climate change includes increasing the average global temperature, which increases average global evaporation, which creates more clouds. More clouds reflect more heat back to Earth, which raises the average global temperatures and worsens climate change. This speeds up the rate of climate change.
  • So which is it? Probably NOT Theory #1. Maybe Theory #2… or maybe it’s Theory #3? Scientists aren’t quite sure yet, so neither am I, but the evidence is stacking against Theory #1 leaving two possible options. The next big question seems to be surrounding the size of the effects of Theory #2 and Theory #3.

    Using what you just read about cloud formation, the earth’s energy budget, greenhouse gases, and climate change (Woah. You just learned a lot!), what do you think? What’s the climate-cloud relationship?

    If you want, you can read more about what scientists are saying about the climate-cloud relationship here:

Sep
08
2011

The Moon's North Pole
The Moon's North PoleCourtesy NASA/GSFC/Arizona State University
Another awesome image from NASA's Image of the Day.

The Earth's moon has been an endless source of fascination for humanity for thousands of years. When at last Apollo 11 landed on the moon's surface in 1969, the crew found a desolate, lifeless orb, but one which still fascinates scientist and non-scientist alike.

This image of the moon's north polar region was taken by the Lunar Reconnaissance Orbiter Camera, or LROC. One of the primary scientific objectives of LROC is to identify regions of permanent shadow and near-permanent illumination. Since the start of the mission, LROC has acquired thousands of Wide Angle Camera images approaching the north pole. From these images, scientists produced this mosaic, which is composed of 983 images taken over a one month period during northern summer. This mosaic shows the pole when it is best illuminated, regions that are in shadow are candidates for permanent shadow.

Jul
12
2011

The Route: We will be entering at entry point #16 Moose/Portage River and exiting at entry point #43 Bower Trout Lake.   The route was designed to expose us to a wide range of use areas within the BWCAW.
The Route: We will be entering at entry point #16 Moose/Portage River and exiting at entry point #43 Bower Trout Lake. The route was designed to expose us to a wide range of use areas within the BWCAW.Courtesy The Great Pack Out
In honor of National Public Lands Day (9/24/2011), my brother and I are going to spend two weeks paddling over 120 miles across the Boundary Waters Canoe Area Wilderness (BWCAW) documenting and collecting all the trash that we find. My brother and I have been paddling in the BWCAW for 23 years and over the last few years have noticed an increase in the amount of garbage we encounter on portages and at campsites. So we started wondering how much trash is actually out there. Is it isolated to the highly used areas near the edges or endemic to the entire BWCAW? In doing some research on the wilderness we discovered that the BWCAW comprises less then 1% of the U.S. National Wilderness Areas yet receives greater then 10% of the recreational activity. What effect does this recreational density have on the quality of the wilderness?

No one really knows. Studies have not been completed. That’s why my brother and I have decided to check it out. We are going to paddle the BWCAW from west to east documenting, collecting, and packing out all the trash we encounter along the way. We will inventory and catalog everything we find and create trash density maps to aid wilderness resource managers focus education and clean up efforts. Who knows, maybe we will inspire others to clean up the BWCAW next year on National Public Lands Day and every day.

Check out our blog for updates and we'll check in following the trip to report our findings.

Jul
11
2011

Have you ever wanted to get involved in scientific research, but figured you weren't qualified? It turns out that scientists need help from people like you all over the world. Citizen science has been a popular pastime for nerdy types for quite a while, and now, online projects are connecting citizen scientists using social media.

Spiral Galaxy: Citizen scientists sort through images like this one from the Hubble Space Telescope at Galaxy Zoo.
Spiral Galaxy: Citizen scientists sort through images like this one from the Hubble Space Telescope at Galaxy Zoo.Courtesy NASA

What is citizen science, you ask? It takes many forms, but the ultimate goal is for normal folks like you and me to lend our time and abilities to scientists--to collect data, tag birds, photograph species--the list goes on. Amateurs help scientists by extending their observational reach--a network of 40 citizens all over the country can make more observations than 2-3 scientists in one location. They also help scientists by performing simple tasks that can be time-consuming but don't ultimately require specialized training.

Whether you're interested in plants, animals, climate, weather, pollution, or astronomy, there are plenty of ways to get involved--Cornell Lab of Ornithology's Citizen Science Central is a clearinghouse of citizen science projects. Some examples include:

You can even use your computer to model climate change. In these projects, it's important to follow directions from the scientists, to make sure your data and other contributions are usable. But no matter how you get involved, it's a great way to help develop a better understanding of the world around us, which helps pave the way for a better future.

Jun
24
2011

A star is born: Artist conception of a protostar
A star is born: Artist conception of a protostarCourtesy NASA/Caltech
Scientists have been studying a newly-forming star that’s blasting incredibly hot and gigantic pulses of water from its poles. The extreme temperature at work (180,000 degrees F.) means the water isn’t in liquid form but rather a super-hot concoction of unfused hydrogen and oxygen atoms. As the jet streams shoot into space away from the star’s accretion disk and outer gas cloud, they cool and the atoms interact with dust and each other, and water molecules form as ice.

The protostar, known as L1448-MM, is 750 light years from Earth, and located in the sky near the Pleiades star cluser. Using the European Space Agency’s,Herschel infrared orbiting telescope astronomers are able to measure the elements making up the baby star, and its bizarre behavior. Each powerful jet pulsating from the center of the star shoots “the equivalent of a hundred million times the water flowing through the Amazon River every second”, at a speed of about 120,000 miles per hour. More incredible is the fact that each “pulse” is estimated to last for about a year! Merely a flash of time in cosmic terms.

Each pulse produces shockwave in the surrounding space. Scientists are uncertain of how long the pulsing phase continues during a star’s birth. It could be anywhere from 1 to 10 million years. But astronomers think “water” fountains like that detected on L1448-MM are a common occurrence in the creation of stars, and that our own Sun went through the same process as it was forming.

SOURCE and LINKS
Physorg.com story
European Space Agency
Star formation info
More about L1448-MM

Jun
05
2011

Scouring for fossils: (L to R) Ashley, John, and Chris search a hillside in Lilydale Regional Park for fossils.
Scouring for fossils: (L to R) Ashley, John, and Chris search a hillside in Lilydale Regional Park for fossils.Courtesy Mark Ryan
Summer seems to have finally arrived in Minnesota and that can mean only one thing: another season of fossil collecting is here. This year, due to near-record snowfall and spring floods, the St. Paul Parks department delayed issuing collecting permits for Lilydale Regional Park, one of the best fossil collecting sites in the Twin Cities. The park is located on the bluffs across the river from downtown St. Paul and is the former quarry and manufacturing site of the now defunct Twin Cities Brick Company. You can enter the park from above near Cherokee Park, or below from Harriet Island. Either way entails hiking a bit of a distance. There's a parking lot just off Water Street, and street and lot parking near Cherokee Park. Download map

Lilydale trail map: Located at the Bruce Vento Overlook near Cherokee Park.
Lilydale trail map: Located at the Bruce Vento Overlook near Cherokee Park.Courtesy Mark Ryan (photo)
The first permits for the "Brickyards" were issued last week, so a few of us from the Science Museum headed over to the park to spend some time searching for the fossilized remains of the marine life that once populated Minnesota during the Late Ordovician Period some 460 million years ago. Back then, much of the state was covered by a shallow, tropical sea, situated below the equator. Times certainly have changed.

The abundant fauna living in that prehistoric sea included reef-building bryozoans (the most commonly found fossil), brachiopods, lily-like crinoids, gastropods, horn coral, predatory cephalopods and everyone’s favorite, trilobites.

Decorah exposure at Lilydale quarries: John is dwarfed by the quarry wall at Lilydale Regional Park's West Clay Pit. The rocks exposed here are Late Ordovician in age (450-470 million years old), and contain fossils of marine life from a shallow sea environment that once covered southern Minnesota.
Decorah exposure at Lilydale quarries: John is dwarfed by the quarry wall at Lilydale Regional Park's West Clay Pit. The rocks exposed here are Late Ordovician in age (450-470 million years old), and contain fossils of marine life from a shallow sea environment that once covered southern Minnesota.Courtesy Mark Ryan
In general, there are three areas to collect fossils at Lilydale: the East, Middle, and West clay pits. Signs posted in several spots help direct you to collecting locations, but once you’re in the park you can find fossils just about anywhere.

The fossil quarries at Lilydale expose the Platteville and Decorah Formations that overlie the St. Peter Sandstone that forms the base of the bluffs found along the Mississippi. The Decorah shale here is about 90 feet thick and easily reconstitutes back into very sticky clay whenever rain or seeping ground water mix with it. But that usually won’t deter most hardened fossil hunters.

Receptaculites: John found the fossil just laying on the ground. It measures about 8 inches across.
Receptaculites: John found the fossil just laying on the ground. It measures about 8 inches across.Courtesy Mark Ryan
Multiple trilobites: Slab of Lilydale quarry shale loaded with the heads and other remains of trilobites and brachiopods. One head (cephalon) is enlarged for detail.
Multiple trilobites: Slab of Lilydale quarry shale loaded with the heads and other remains of trilobites and brachiopods. One head (cephalon) is enlarged for detail.Courtesy Mark Ryan
We had a pretty good day at Lilydale finding the usual crop of fossils, such as crinoid rings, brachiopod shells, and bryozoa branches. Chris pointed out some trilobite heads (cephalon) Ashley and I had overlooked in a couple small slabs of shale. John picked up a nice receptaculites specimen just setting on the ground. Later, while scanning the bluff, a piece of gray shale caught my eye. It was about six-inches in diameter and contained several brachiopods. But upon closer examination, I counted the remains of at least a dozen trilobites, mostly the heads of Eomonorachus intermedius.

Ordovician trilobite: Ashely displays John's fabulous find (Isotelus gigas?) from the Lilydale quarries.
Ordovician trilobite: Ashely displays John's fabulous find (Isotelus gigas?) from the Lilydale quarries.Courtesy Mark Ryan
But what my fossil possessed in quantity, John’s big find of the day overshadowed in quality. Picking through the clay piles that had slumped down from the top of the quarry since last fall, John plucked out a very well-preserved, rolled specimen of Isotelus gigas?, measuring about 1-1/2 to 2 inches across! It’s the largest trilobite I’ve witnessed come out of the Decorah. All the ones I’ve ever found were incomplete and maybe the size of a kernal of corn at best. But John’s fossil was a doozy. Unrolled it would measure a good 3 inches in length, if not more. I don’t like being outdone so I told John there’s no reason for him to hunt for fossils anymore - he’ll never find another specimen like that. But we both know he won’t be able to stop. That’s just the way fossil hunting is; there’s always the possibility of discovering a bigger and better find next time you go out.

Typical "shell hash" slab found at Lilydale
Typical "shell hash" slab found at LilydaleCourtesy Mark Ryan
Many of the Decorah fossils can be found weathering out on the surface, so you don’t need much in the way of tools. Some people like to bring a large bucket to serve as a stool while they’re in the quarries, and then for carrying out their fossils when leaving. I usually bring some plastic sandwich or freezer bags to hold smaller fossils. Some people use tissue paper or aluminum foil to wrap and protect their more precious finds. I do that sometimes. The clay pits also contain lenses of fossiliferous rock forming what’s known as "shell hash" – a chaotic jumble of fauna preserved in a matrix of limestone or shale. A rock hammer sometimes come in handy for breaking up large slabs into smaller, more portable ones, or for climbing the quarry banks.

School kids and buses swarm the Lilydale parking lot: Fossil-hunting in the quarries is a favorite extracurricular activity.
School kids and buses swarm the Lilydale parking lot: Fossil-hunting in the quarries is a favorite extracurricular activity.Courtesy Mark Ryan
If you go to hunting in the Lilydale quarries, you’ll want to bring along some water, and bug dope - mosquitoes weren’t yet a problem, but a couple wood ticks showed up. The driest parts of the quarry are of course in the sun, so if you're like me and burn easily, and don't want to spend most of your time searching in the muddier shade, it’s best to apply some sun-block lotion to your exposed skin. John also spotted several patches of poison ivy while we were scouring the West Clay Pit so you should keep that in mind, too. It’s an isolated area so be aware of your surroundings and it’s probably best to go with someone else. The quarry walls and hillsides can be unstable and treacherous. I've seen people take serious tumbles down the quarry face. Be aware, too, that there are no bathroom facilities at the quarries. There are lots of woods and bushes, though.

If you’re going to be there for a while you might consider bringing something to eat, too. Ashley brought a delicious seven-course gourmet meal for all of us to enjoy. Okay, that’s a slight exaggeration (it was only three courses), but after a few hours of intensive fossil hunting it sure tasted like one. Ashley has secured for herself a guaranteed slot in all future fossil hunting expeditions.

For information on acquiring a fossil-collecting permit for Lilydale, check out the Lilydale Regional Park permit page. Individuals and small groups of less than ten people pay $10 for a day permit. Larger groups pay more.

The Minnesota Geological Survey offers a nice information brochure about local geology, collecting, and identifying fossils at Lilydale and elsewhere around the Twin Cities. Download it here

Going home: The trail back to the Water Street parking lot
Going home: The trail back to the Water Street parking lotCourtesy Mark Ryan
I've listed a few more websites below to help get you started and make your fossil-collecting excursion to Lilydale more fun and informative. In general, hunting for fossils is kind of like fishing; you get to enjoy the outdoors, you get to occasionally make some nice catches (finds), and you get to bring them home and clean them. But best of all (besides not having to eat them), you get to boast to your friends about "netting" some sea creatures that are over 450 million years old. That, for me, is a fish story that's way more impressive than any fish tale concerning some old lunker that got away. So get out there and dig up the next great cephalopod fossil. You'll know exactly what I'm talking about.

LINKS

List of fossil sites and equipment
More trilobite info
More about horn coral
Collecting Fossils in Minnesota (previous Buzz post)
Minnesota DNR info page on fossils
Fossil Collecting in the Twin Cities
Lilydale trail map
Lilydale Regional Park
More about Lilydale Regional Park

May
22
2011

The Icelandic Meteorological Office announced Saturday May 21 at 2:00 pm CDT the eruption of the volcano Grímsvötn in Iceland (N64,24, W0172) following a short period of tremor. This is Iceland’s largest volcano. The eruption started under ice but spewed a plume up to 65,000 feet. Grímsvötn is a well monitored volcano. It last erupted in October 2004 and lasted about a week.

This eruption was larger than last year’s Eyjafjallajokull eruption, but will likely have less impact on air traffic. While Keflavik, the Iceland’s larges airport, was shut down, the ash plume from Grímsvötn is currently drifting east and north away from Europe.

Volcanic Ash Advisory Centers are set up across the globe to monitor volcanic ash and issue warnings as appropriate. These centers make use of satellite observations to monitor the eruptions and the movement of the ash cloud. Below is a link to a satellite animation of the eruption. This is a European satellite and the time between images is about 15 minutes.

http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2011/05/110521_m...

May
12
2011

Mississippi River Levee in Baton Rouge, LA, taken May 11th 2011.: Panorama of the Mississippi River levee in Baton Rouge, LA near Louisiana State University, taken May 11th 2011.
Mississippi River Levee in Baton Rouge, LA, taken May 11th 2011.: Panorama of the Mississippi River levee in Baton Rouge, LA near Louisiana State University, taken May 11th 2011.Courtesy Azure Bevington
You might have heard about the terrible flooding that is occurring all along the Mighty Mississippi. As I write this I am sitting in Baton Rouge, Louisiana hoping the levees will hold. Normally the river in Baton Rouge is far below the tops of the levees. Flood stage, which is the water level at which the river would begin to flood surrounding areas without the levees acting as barriers, is 35 ft. Right now the water level is 42.8 ft and has risen 8 ft in just the last week. It is projected to crest at 47.5 ft and remain at that level for 8 to 10 days; this is higher than the previous record set in May 1927 of 47.28 ft. The tops of the levees that protect Baton Rouge are between 47 and 50 ft, they are currently sandbagging in areas less than 48 ft. Besides the possibility of overtopping there are also other problems that we need to look out for. When the river level remains high for an extended period of time the water can seep in and begin to saturate the soil, this can possibly weaken the levee structure. There is also the possibility of water going under the levee; this can result in sand boils, where the water bubbles up through the soil. It is very unlikely that this will happen, as the levees are strong and well constructed, but we need to be on the lookout for any problems.

Here in Baton Rouge we are much better off than many who live in communities within the Atchafalaya Basin, where the expected opening of the Morganza spillway could cause flooding of over 3 million acres (Click here to see a map of projected flooding in the basin) Many of these folks have already begun to sandbag their homes and to prepare to leave the area. The Morganza spillway is a large controlled gated structure that will divert water from the Mississippi River into the Atchafalaya Basin. The Atchafalaya Basin is a low lying cypress swamp that normally receives 30% of the flow of the Mississippi River through the Old River Control structure through the Atchafalaya River that winds its way through the swamp. This flood is projected to be larger than the 1973 flood and possibly even larger than the 1927 flood that devastated communities along the river, and brought about the passage of Flood Control Act of 1928. The magnitude of this year’s flood has already resulted in the opening of the Bonnet Carré spillway which diverts water into Lake Pontchartrain, this reduces the water levels as the River flows past New Orleans.

Stay tuned for updates on the flooding in Louisiana.

Have any of you been affected by the flood waters?

Apr
28
2011

A number of severe thunderstorms have swept through the SE US recently. Some storms generated tornadoes that were truly devastating. The news channels have many photos of the ground destruction. We can see the path of the storms in satellite images. Here is a link to one of those images.

A comparison of 250-meter resolution image from a NASA MODIS instrument at 0.65 µm and 0.87 µm visible channel images centered on Tuscaloosa, Alabama on 28 April 2011 showed signatures of a few of the larger and longer tornado damage paths from the historic tornado outbreak (SPC storm reports) that occurred on 27 April 2011. The yellow arrows point to some of the paths.

Here is a link to an animation between the two channelsMODIS Image of Tornado Paths on 28 April 2011: NASA Satellite image see tornado path
MODIS Image of Tornado Paths on 28 April 2011: NASA Satellite image see tornado pathCourtesy CIMSS UW-Madison

http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2011/04/110428_m...

Apr
16
2011

For some reason paleontology news this week seems to cover the whole sensory gamut. First off, there’s a new discovery in China of a Mesozoic mammal named Liaoconodon hui that adds more transitional evidence regarding the evolution of the reptilian lower jaw into the middle ear bones found in mammals. The research was done by paleontologists from the American Museum of Natural History and the Chinese Academy of Sciences.

The guys over at Witmer Lab write about being involved in a study of the evolution of olfaction from small theropod dinosaurs to modern birds. The olfactory bulb is the part of the brain that detects odor, and it seems some modern birds inherited a pretty good sense of smell from their dinosaurian ancestors. Here's some video about it from the Witmer Lab site.

In the seeing department Jennifer Viegas over at Discovery News has a slide show presentation (with text) about a new study appearing in Science that suggests some dinosaurs and other prehistoric reptiles were nocturnal. The study is based on the sceleral ring and larger eye sockets found in the fossil remains of some prehistoric animals. Larry Witmer also mentions the subject on his blog (it’s located below the olfaction post).

Touch and taste – the last two senses - are covered in a new study of lice evolution at the University of Illinois-Urbana, and with the discovery of a new, toothy dinosaur in New Mexico.

Kevin Johnson, an ornithologist at the UI-Urbana, proposes that since lice seem to specialize in the way they annoy their host animals, it’s likely that lice that cause today’s birds to nit-pick, scratch and preen, are descended from lice that pestered feathered dinosaurs. You can read about Johnson’s research here.

Ghost Ranch, New Mexico: The red beds here have produced fossils of a new early carnivorous dinosaur.
Ghost Ranch, New Mexico: The red beds here have produced fossils of a new early carnivorous dinosaur.Courtesy Mark Ryan
Lastly, Daemonosaurus chauliodus ("evil spirit reptile with outstanding teeth") is a new carnivorous dinosaur species found recently at Ghost Ranch in New Mexico. The buck-toothed theropod more-than-likely feasted on all the other creatures it shared its environment with 200 million years ago during the Triassic (yes, I know I’m probably stretching the taste sensory categorization here but I needed something). The discovery of Daemonosaurus in a block of Coelophysis remains is important because it alters scientific thought on the early history of carnivorous dinosaurs. The study was led by vertebrate paleontologist Hans-Dieter Sues of the Smithsonian and appears in the journal Proceedings of the Royal Society B. You can also read about it at Dinosaur Tracking.