Science Data Exploration

Earth as a system,
from Investigating Earth Systems

Learning about the Earth as a system provides a wide range of opportunities for students to explore various sets of data to better understand the individual components — the atmosphere, the hydrosphere, the geosphere, the biosphere — and how they are interconnected. Throughout our study of Earth science, I give students multiple occasions to interpret, analyze, and evaluate various Earth system data. Over the years, I've built up a collection of simple, useful datasets for students to manipulate using graphing software such as Microsoft Excel, Create A Graph, or Google Spreadsheet. Here is a sampling of some of these data.

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The Atmosphere

Each year, we begin our study of the Earth system within the atmosphere—the gaseous envelope surrounding our planet which has evolved from and interacts with the other "spheres" of the Earth system. Investigating the composition of Earth's atmosphere is thus a logical first step in our data exploration.

Composition of Earth's Atmosphere

Data source: Wallace, J.M. and Hobbs, P.V., 1977, Atmospheric Science—An Introductory Survey

Compound	Percent
Nitrogen	78.08
Oxygen	20.95
Argon	0.93
Trace Gases	0.04

It is useful to refer back to this set of data often during our climate studies, reminding students that the tiny fraction of trace gases are responsible for the greenhouse effect and instrumental in maintaining the balance in Earth's energy budget.

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The Hydrosphere 

As we move from the atmosphere to the hydrosphere, students explore how water is distributed across our planet as well as examine the composition of ocean water. When examining global water distribution, it is useful to have students consider how much of this water is readily available for daily human use. Additionally, this set of data provides an opportunity for students to learn how to create "pie-of-pie" graphs to best show data that has a large range of values.

Global Water Distribution

Data source: Gleick, P. H., 1996, Water resources. In Encyclopedia of Climate and Weather, ed. by S. H. Schneider, Oxford University Press, New York, vol. 2, pp. 817-823

Water Source	Percent
Oceans, Seas, and Bays	96.5
Ice Caps, Glaciers, and Permanent Snow	1.74
Groundwater (fresh)	0.76
Groundwater (saline)	0.94
Soil Moisture	0.001
Ground Ice and Permafrost	0.022
Lakes (fresh)	0.007
Lakes (saline)	0.006
Atmosphere	0.001
Swamp Water	0.0008
Rivers	0.0002
Biological Water	0.0001

"Have you ever had a mouthful of ocean water?" is a great question to ask students when introducing the next set of data. It elicits an immediate "Ewww!" response and primes students to think about the compounds contained in that mouthful of water and how they got there.

Composition of Ocean Water

Data source: National Science Teachers Association, 1992, Project Earth Science, Physical Oceanography

Element	Percent
Oxygen	85.7
Hydrogen	10.8
Chlorine	1.9
Sodium	1.05
Magnesium	0.135
Sulfur	0.0885
Calcium	0.04
Potassium	0.038
Bromine	0.0065
Carbon	0.0028
Other	0.001

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The Geosphere 

When we transition to our studies of the geosphere, students take a look at data comprising the Earth's crust. The composition of Earth's crust shows many commonalities with the composition of ocean water data above. It is useful to have students compare and contrast the two sets of data. It is quite a challenging discussion when students are asked to explain how the Earth's crust can be nearly 50% oxygen; it helps reinforce the meaning of "compound."

Composition of Earth's Crust

Data source: Glencoe Earth Science, 1999

Element	Percent
Oxygen	46.6
Silicon	27.7
Aluminum	8.1
Iron	5.0
Calcium	3.6
Sodium	2.8
Potassium	2.6
Magnesium	2.1
Other	1.5

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The Solar System 

Finally, as we move from the safety of our home planet and journey into the rest of the solar system, it is interesting to ponder the composition of the solar system itself. Once again, it is useful to compare and contrast the similarities and differences among the various sets of data ("What's up with all that hydrogen?"). It is also interesting to ponder how knowledge of Earth's composition can help scientists understand and make sense of the compositions of other objects in our solar system.

Composition of the Solar System

Data source: Mineral Information Institute, Golden CO, 2002, http://www.mii.org

Element	Percent
Hydrogen	91.04
Helium	8.81
Oxygen	0.08
Carbon	0.03
Neon	0.01
Nitrogen	0.01
Magnesium	0.004
Silicon	0.003
Iron	0.003

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With an endless variety of Earth system data available, students have many opportunities to deeply engage in scientific analysis and interpretation as well as develop an appreciation for the Earth as an interconnected system. If you use other interesting datasets, please feel free to share them in the comments...

Analyzing Local Weather Data

These days, there are numerous sources and tools on the internet that provide access to live weather data, which can be used to practice and refine data interpretation skills. In our school district, data interpretation is one of the essential middle level science learnings:

"Students can interpret, analyze, and evaluate data and recognize bias in order to formulate logical conclusions."

ASOS: the National Weather Service's
automated weather observing network

The National Weather Service provides a plethora of weather data that is ideal for use in the classroom. In my last post, I talked about hurricane data. In this post, I'd like to explore local weather data.

On a daily, monthly, and yearly basis, the National Weather Service records and archives basic weather data such as temperature, pressure, wind, precipitation, etc. In most places across the United States, there is more than 100 years worth of data in the climate archives—all of this data is accessible online. This data can be used in the classroom to analyze local patterns and trends.

To access the National Weather Service climate data:

1. Go to http://www.weather.gov
2. Type your zip code into the Local Forecast box in the top left corner
3. On the next page, select the link to your local National Weather Service office in the top left corner—it looks like "NWS Denver-Boulder CO"
4. On the next page, look for the Climate section along the left panel and select the Local link. 

From here, you and your students have access to all of the local climate data and records. One of the reports I use with my students is the "Climatological Summary Month-to-Date," which provides a table of the current month's daily weather statistics. Each day during one month, we start our science class by pulling up this page and recording the previous day's high temperature, low temperature, and precipitation in our own data tables. At the end of the month, we graph, summarize, and analyze the data. Students reflect on the following questions:

• What was the average high temperature for the month?
• What was the average low temperature for the month?
• What was the total precipitation for the month?
• How much warmer or colder than normal was this month?
• How much wetter or drier than normal was this month?
• Based on the data, how would you summarize this month's weather?
• Were there any notable or unusual weather events this month?
• Were there any record weather events this month?

We should seek every opportunity to bring authentic data into the classroom to promote scientific literacy and help students make real world connections. One of my favorite quotes that bears repeating (often):

"If you're scientifically literate, the world looks very different to you, and that understanding empowers you..." —Neil deGrasse Tyson, Astrophysicist

The National Weather Service is but one of the many science organizations that publishes useful data online. I will discuss others in future posts...

Data Interpretation and Hurricane Tracking

Hurricane season always provides an authentic opportunity to learn about the process of science. These days, there are numerous sources and tools on the internet that provide access to live weather data, which can be used to practice and refine data interpretation skills. In our school district, data interpretation is one of the essential middle level science learnings:

"Students can interpret, analyze, and evaluate data and recognize bias in order to formulate logical conclusions."

This past week, Hurricane Irene struck the eastern United States, causing major flooding and destruction in many areas. A plethora of science instruments—land-based, sea-based, plane-based, and satellite-based—monitored Irene's vital signs as it trekked across the planet and affected millions of humans. These instruments captured a wealth of data and images that can be used in the classroom to help students better understand hurricanes as well as reinforce how science works.

Hurricane Irene, Doppler Radar Animation,
courtesy of the Weather Underground

Precipitation data from land-based Doppler radars is one of the types of information collected during a hurricane. Doppler radars produce colorful images and animations that can be used to stimulate student conversations about science—sort of a digital dissection. During Hurricane Irene, I captured a Doppler radar animation centered around the hours when the cyclone first made landfall on the outer banks of North Carolina (click the image to the right to view the animation). The animation loop provides enough information to discuss and infer basic weather variables such as tropical cyclone circulation, forward storm motion, wind speed, wind direction, precipitation rates and amounts, and more. (Details for capturing a Doppler animation loop are at the end of this post.)

When using images and animations, I ask students three main questions:

1. What do you see? (observations) 
2. How do you know? (evidence) 
3. What can you infer? (interpretation) 

I have students practice the "What do you see?" and "How do you know?" questions first as small table groups, then share the "What can you infer?" question as a whole class. During the table discussions, I circulate around the classroom as a background observer and facilitator—listening to their conversations, asking clarifying questions, and nudging everyone in the group to participate equitably. There are no right or wrong answers during these small table discussions; it is an opportunity for students to hone their science skills. This activity empowers students to have authentic peer conversations about real science data, a basic "process of science" principle. Additionally, this activity allows students to practice their powers of observation and interpretation together in preparation for hands-on lab experiments in which they will need to collect and interpret their own data.

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Capturing a Doppler Animation Loop

There are numerous sources of weather information on the internet, but my favorite is the Weather Underground. Their maps, graphics, and animations are well-designed, easy-to-read, colorful, accessible, and appropriately scientific, which makes them an ideal source for the science classroom.

To capture a Doppler animation loop, do the following:

• Go to the Weather Underground website, and of course bookmark/favorite it for future use.
• Select the Radar link under the Maps & Radar tab on the main page.
• Select one of the Doppler radar sites (indicated by + symbols) closest to the area of interest.
• To generate an animated loop on the radar page, adjust the Radar Controls on the right side of the page, then click the Update Radar Map button. For Hurricane Irene, I modified the Animate Frames box to 40, and the Frame Delay to medium, while leaving the other options at their default settings.
• Once the full animation loads, select the View/Save This Image link at the bottom of the loop to display the animation on a separate web page. Then, save a copy of the animation to your computer (usually File-->Save As…). This animation can be replayed on your favorite web browser for later classroom use.