9.3.2.2 Global Climate
Explain how Earth's rotation, ocean currents, configuration of mountain ranges, and composition of the atmosphere influence the absorption and distribution of energy, which contributes to global climatic patterns.
Explain how evidence from the geologic record, including ice core samples, indicates that climate changes have occurred at varying rates over geologic time and continue to occur today.
Overview
MN Standard in lay terms:
Earth's atmospheric composition leads to the absorption of many high-energy wavelengths of solar light (all parts of the electromagnetic spectrum), preventing gamma rays and X-rays from reaching the Earth's surface, and enabling the penetration of primarily ultraviolet (UV) and visible light. Topographic features like mountains and bodies of water (e.g., oceans, seas, lakes, rivers, ponds, etc.), and the composition of the landscape (e.g., liquid water, ice, rock, sand, metal structures, asphalt, trees, etc.) all affect energy absorption and the distribution of energy on the planet; in general, darker-colored objects absorb more solar energy and reflect less while lighter colored objects reflect more energy and absorb less. Large-scale atmospheric circulation is driven by the uneven heating of Earth's surface, the cycle of day/night, and seasonality due to Earth's axial tilt (about 23.5 degrees).
Big Ideas:
Earth Science Literacy: The Big Ideas and Supporting Concepts of Earth Science.
Earth Science Literacy Big Idea 1: Earth scientists use repeatable observations and testable ideas to understand and explain our planet.
Earth Science Literacy Big Idea 3: Earth is a complex system of interacting rock, water, air, and life.
3.2: All Earth processes are the result of energy flowing and mass cycling within and between Earth's systems.
3.7: Changes in part of one system can cause new changes to that system or to other systems, often in surprising and complex ways.
3.8: Earth's climate is an example of how complex interactions among systems can result in relatively sudden and significant changes.
Earth Science Literacy Big Idea 4: Earth is continuously changing.
Earth Science Literacy Big Idea 5: Earth is the water planet.
5.3: Water's unique combination of physical and chemical properties are essential to the dynamics of all of Earth's systems.
Climate Literacy: The Essential Principles of Climate Science.
Principle 1: The sun is the primary source of energy for Earth's climate system.
Principle 2: Climate is regulated by complex interactions among components of the Earth system.
Principle 4: Climate varies over space and time through both natural and man-made processes.
Principle 5: Our understanding of the climate system is improved through observations, theoretical studies, and modeling.
MN Standard Benchmarks:
9.3.2.2.1. Explain how Earth's rotation, ocean currents, configuration of mountain ranges, and composition of the atmosphere influence the absorption and distribution of energy, which contributes to global climatic patterns.
9.3.2.2.2. Explain how the evidence from the geologic record, including ice core samples, indicates that climate changes have occurred at varying rates over geologic time and continue to occur today.
THE ESSENTIALS:
A quote, cartoon or video clip link directly related to the standard.
NASA Explorer. (2009). Taking Earth's temperature [video clip].
To start a lesson on this standard (9.3.2.2), watch the video clip from NASA (provided at the beginning of the Essentials section). This could be used to open up a discussion about climate change as it is described in the media today, while leading to the consideration of what determines global climate on the Earth and also discussing the natural cycles involved in influencing global climate (e.g., solar sunspot activity, Milankovitch Cycles, greenhouse gas concentrations, land cover and distribution across the Earth's surface, etc.).
NSES Content Standard D Earth and Space Science (grades 9-12)
Energy in the Earth system
Earth systems have internal and external sources of energy, both of which create heat. The sun is the major external source of energy. Two primary sources of internal energy are the decay of radioactive isotopes and the gravitational energy from the earth's original formation.
Heating of earth's surface and atmosphere by the sun drives convection within the atmosphere and oceans, producing winds and ocean currents.
Global climate is determined by energy transfer from the sun at and near the earth's surface. This energy transfer is influenced by dynamic processes such as cloud cover and the earth's rotation, and static conditions such as the position of mountain ranges and oceans.
The origin and evolution of the Earth system
Geologic time can be estimated by observing rock sequences and using fossils to correlate the sequences at various locations. Current methods include using the known decay rates of radioactive isotopes present in rocks to measure the time since the rock was formed.
Interactions among the solid earth, the oceans, the atmosphere, and organisms have resulted in the ongoing evolution of the earth system. We can observe some changes such as earthquakes and volcanic eruptions on a human time scale, but many processes such as mountain building and plate movements take place over hundreds of millions of years.
Weather and climate.
Benchmarks of Science Literacy:
Project 2061: Benchmarks for Science Literacy.
Chapter 4b:
By the end of the 12th grade, students should know that
Transfer of thermal energy between the atmosphere and the land or oceans produces temperature gradients in the atmosphere and the oceans. Regions at different temperatures rise or sink or mix, resulting in winds and ocean currents. These winds and ocean currents, which are also affected by the earth's rotation and the shape of the land, carry thermal energy from warm to cool areas. 4B/H2*
Because the earth turns daily on an axis that is tilted relative to the plane of the earth's yearly orbit around the sun, sunlight falls more intensely on different parts of the earth during the year. The difference in intensity of sunlight and the resulting warming of the earth's surface produces the seasonal variations in temperature. 4B/H3** (BSL)
Greenhouse gases in the atmosphere, such as carbon dioxide and water vapor, are transparent to much of the incoming sunlight but not to the infrared light from the warmed surface of the earth. When greenhouse gases increase, more thermal energy is trapped in the atmosphere, and the temperature of the earth increases the light energy radiated into space until it again equals the light energy absorbed from the sun. 4B/H4** (SFAA)
Climatic conditions result from latitude, altitude, and from the position of mountain ranges, oceans, and lakes. Dynamic processes such as cloud formation, ocean currents, and atmospheric circulation patterns influence climates as well. 4B/H5** (NSES)
The earth's climates have changed in the past, are currently changing, and are expected to change in the future, primarily due to changes in the amount of light reaching places on the earth and the composition of the atmosphere. The burning of fossil fuels in the last century has increased the amount of greenhouse gases in the atmosphere, which has contributed to Earth's warming. 4B/H6** (SFAA)
Chapter 11a:
By the end of the 12th grade, students should know that
Even in some very simple systems, it may not always be possible to predict accurately the result of changing some part or connection. 11A/H4
Systems may be so closely related that there is no way to draw boundaries that separate all parts of one from all parts of the other. 11A/H5** (SFAA)
Chapter 11c:
By the end of the 12th grade, students should know that
If a system in equilibrium is disturbed, it may return to a very similar state of equilibrium, or it may undergo a radical change until the system achieves a new state of equilibrium with very different conditions, or it may fail to achieve any type of equilibrium. 11C/H1*
The present arises from the conditions of the past and, in turn, affects what is possible in the future. 11C/H6*
Trends that follow a pattern that can be described mathematically can be used to estimate how long a process has been going on. 11C/H8** (SFAA)
It is not always easy to recognize meaningful patterns of change in a set of data. Data that appear to be completely irregular may be shown by statistical analysis to have underlying trends or cycles. On the other hand, trends or cycles that appear in data may sometimes be shown by statistical analysis to be easily explainable as being attributable only to randomness or coincidence. 11C/H9** (SFAA)
Common Core Standards:
V. Geography. B. Maps.
The student will use and create maps and globes to locate people, places, and things.
V. Geography. C. Physical Features and Processes
The student will identify physical characteristics of places and use this knowledge to define regions, their relationships among regions, and their patterns of change.
V. Geography. D. Interconnections
The student will demonstrate how various regional frameworks are used to analyze the variation in physical environment.
Misconceptions
Frasier, A.B. (n.d.). Bad Meteorology.
- The reason clouds form when air cools is that cold air cannot hold as much water vapor as warm air.
- The greenhouse effect is caused when gasses in the atmosphere behave as a blanket and trap radiation which is then reradiated to the earth.
- The water in a sink (or toilet) rotates one way as it drains in the northern hemisphere and the other way in the southern hemisphere. Called the Coriolis Effect, it is caused by the rotation of the earth.
- Raindrops are shaped like teardrops.
Henriques, L. (2000). Children's misconceptions about the weather: A review of the literature. Paper presented at the annual meeting of the National Association of Research in Science Teaching, New Orleans, LA, April 29, 2000.
- Water only gets evaporated from the ocean or lakes.
- Rain falls out of the sky when the clouds evaporate.
- Clouds are [like] sponges that hold water.
- Humid air is oppressive and heavy; humid air is more dense than dry air.
Others:
- The ozone hole is [significantly] related to the global warming issue.
Vignette
Mr. H's high school students are learning about global climate. To start off the lesson, Mr. H plays a video clip about how NASA uses instruments and models to determine the temperature of the Earth. After the students view the video clip, they think-pair-share with a partner about one thing they learned about global climate from the NASA video. After a few minutes of conferring with fellow students, Mr. H calls on a few student pairs to share with the class. Mr. H uses the sharing session to begin a large-class discussion about a few hot issues related to global climate, global warming, and human-induced changes in greenhouse gas concentrations; he uses the opportunity to correct some common misconceptions and to introduce global climate as a result of a number of natural cycles, events, and feedbacks.
Over the next few days, Mr. H follows the four-question strategy as a way to further engage students and enable them to explore the global climate change idea in more detail. He asks (first question): "What materials are readily available for conducting investigations on global climate?" Students discuss it and develop an investigation. They use digital temperature probes to study the temperature with height above several surfaces: pavement, grass, and sand. They graph data and compare the surfaces. Mr. H follows up the activity by engaging students in a discussion about human influences on land cover (e.g., building cities, deforestation, snow removal, etc.) and how these may affect the incident radiation on the Earth and contribute to local, regional, and global climate changes. Mr. H then progresses to another (second) question: How does global warming act? The students busy themselves with researching global warming, greenhouse effect, and greenhouse gases. As a class, they list out all of the greenhouse gases the students have identified and discuss the greenhouse effect as it relates to global warming. Mr. H verifies and expands on the science related to shortwave energy conversion to IR by the solid Earth, and its absorption and re-emission by greenhouse gas; which leads to consideration of the entire Earth's energy balance (and time lags in energy inputs and outputs). Mr. H informs students that through using the next two questions, they will have an opportunity to create an investigation to test a hypothesis (or hypotheses). He distributes a sheet to each small group of students with the remaining two questions from the four-question strategy: How can we change the set of global warming materials to affect the action?, and How can we measure or describe the response of global warming to the change? After deliberating for some time, the students come up with several great ideas! One group decides to add carbon dioxide gas to two enclosed containers with different surfaces (e.g., black asphalt and white sand), and measure temperature differences (with thermometers) after specific periods of time. Mr. H challenges the students by inquiring how they will obtain carbon dioxide gas?
Several days later, when students have completed all of their group investigations, Mr. H introduces students to the idea of the "heat island effect" and asks students to consider how the town in which they live affects the local climate. Students use the data they collected earlier (about temperature and different surface cover) to examine Google Earth images of their town and to make projections about the city temperature today relative to the possible temperature of the area before it was settled.
Resources
Instructional suggestions/options:
There is a plethora of information, data, animations, and more, available about climate change given the media coverage of the topic today. To start a lesson on this standard (9.3.2.2), watch the video clip from NASA (provided at the beginning of the Essentials section). This could be used to open up a discussion about climate change as it is described in the media today, while leading to the consideration of what determines global climate on the Earth and also discussing the natural cycles involved in influencing global climate (e.g., solar sunspot activity, Milankovitch Cycles, greenhouse gas concentrations, land cover and distribution across the Earth's surface, etc.). A number of lesson and activity options are presented below, and the more hands-on engagement students can have related to this standard, the better.
Cothron, J.H. (1993). Students and research. Dubuque IA: Kendall/Hunt Publishing.
Four-Question Strategy (see Vignette):Use the four question strategy to generate experimental ideas and to demonstrate the variety of options available for student investigations.
Selected activities :
The following activities may be used to address Benchmark 9.3.2.2.1:
PALS. (2002). RadiationSim.
These simulations were created at Iowa State University to support learning in a large-lecture introductory meteorology class. There are several simulations listed from which to choose, and instructors are encouraged to generate an activity based on one (or more), or allow students to explore them and adjust parameters. They include simulations related to air moving over a mountain and radiation budget relative to different surface coverage.
UCAR. (n.d.) Activity 5: Atmospheric processes: Radiation. ( 9.3.2.2.1)
The activity is a hands-on way to learn about radiation. The activity is tied to the standards and includes teacher guide pages. A specific activity related to surface cover and temperature is housed at the site.
UCAR. (n.d.) Activity 6: Atmospheric processes: Conduction. (9.3.2.2.1)
The activity is a hands-on way to learn about conduction. The activity is tied to the standards and includes teacher guide pages. A specific activity related to heat conduction via several different materials (e.g., copper, aluminum, glass, etc.), and timed to see how long until a wax candle takes to melt when in contact with the opposite end of a rod subjected to heat; best suited as a teacher demonstration.
UCAR. (n.d.) Activity 7: Atmospheric processes: Convection. (9.3.2.2.1)
The activity is a hands-on way to learn about convection. The activity is tied to the standards and includes teacher guide pages. A two-part investigation involving several activities related to observing the movements of a liquid subjected to uneven heating.
Suitable for classroom use with students.
Radiation Budget Activities (geared for grades 5-8, but adaptable for 9-12)
Atmospheric Science Data Center. (2007). Radiation budget lesson plans and activities.
NASA.
A list of hands-on activities, quizzes, and other materials (e.g., games) for teaching students about albedo, radiation budget, and the characteristics of light. (9.3.2.2.1)
Windows to the Universe: (9.3.2.2.1)
NESTA. (2011). Windows to the universe: Earth's radiation budget.
An informational page about the balance of Earth's radiation budget (for the teacher or students).
NOAA. (2009). Surface ocean currents.
An informational page about how the Coriolis force leads to the development of ocean currents (for teachers and/or students).(9.3.2.2.1)
The following activities may be used to address Benchmark 9.3.2.2.2
Taber et al. (2010). Climate history from deep-sea sediments. Earth Exploration Toolbook chapter.
A hands-on activity uniting an online dataset, easily obtainable software analysis tool, and step-by-step directions related to understanding how climate history may be understood from deep-sea sediment studies. The activity may be used to enhance teacher understanding, or may be used with a classroom of students (requires access to computers).
Pfirman, S. (2007). Lab: Vostok ice core.
A hands-on activity designed to assist students in understanding the climate data obtained from the Vostok ice core samples. The activity provides a data set that can be opened in MS Excel and leads students to an understanding of how atmospheric information may be studied from ice cores. (9.3.2.2.2)
SERC. (2011). Exploring paleoclimatology in the classroom using Vostok ice core data.
Another Vostok ice core activity from a reputable source. Students examine data and make interpretations. Included at the site is an activity that provides a data set that can be opened in MS Excel and leads students to manipulate the data in order to understand how atmospheric information may be studied from ice cores. (9.3.2.2.2)
D'Andrea, B. (2011). Why paleoclimate? [video clip]. Exploratorium.
Shake things up in class by showing this video clip in class -- great discussion of ice cover changes over the past 30 years. (9.3.2.2.2)
University of Arizona. (2006). Global climate change: A series of 7 lectures exploring world and ourselves.
A series of video clips about global climate change. Perhaps most suitable for the teacher to view and learn more about the science related to climate change. (9.3.2.2.2)
NASA Global Climate Change web page [lessons, activities, video clips].
A link to NASA's climate change page: includes links to resources and activities.
Essentially a reservoir of educational activities related to climate change. (9.3.2.2.2)
NOAA. (2007). What is paleoclimatology?
Learn more about paleoclimatology and how scientists study climates of the past. Primarily a resource page.(9.3.2.2.2)
Bruckner, M. (2008). Paleoclimatology: How can we infer past climates? Science Education Resource Center, Carleton.
Another informational page about paleoclimatology and how scientists use proxy data to study the climate of Earth's past. (9.3.2.2.2)
Additional resources or links
Ahrens, C.D. (2012). Essentials of meteorology (6th ed.). Brooks Cole.
A great textbook for reviewing meteorology/climate concepts (for teachers), or a useful resource for students completing research reports/projects.
Moran, J.M. (2009). Weather studies: Introduction to atmospheric science (4th ed.). Boston, MA: American Meteorological Association.
A great textbook for reviewing meteorology/climate concepts (for teachers) and published by the American Meteorological Association. Also, a useful resource for students completing research reports/projects.
Intergovernmental Panel on Climate Change (IPCC).
Get all of the latest facts and information about the climate change issue from the IPCC (the foremost authority on the subject). A great resource for teachers to research the issue or for students completing research reports/projects.
Environmental Protection Agency. (2010). Ozone hole science: The facts behind the phaseout.
A number of misconceptions persist about the ozone hole. This is a great page published by the EPA about the ozone hole. Suitable for teachers researching the topic or students researching for papers/projects.
Hoffman, P.F., & Schrag, D.P. (1999, January). Snowball earth. Scientific American.
The Earth has experienced many glacial periods, and perhaps, completely froze over at one time or another. Explore this interesting idea with your students.
Ruddiman, W.F. (2008). Earth's climate: Past and future (2nd ed.). W.H. Freeman.
A great textbook for reviewing climate concepts (for teachers), or a useful resource for students completing research reports/projects.
Earth System Research Laboratory. (2011). United States Interactive Climate Pages. NOAA.
Explore climate data for specific cities and the nation in general at this site.
Maps, timeseries, and climatological factors (e.g., temperature, precipitation, etc.) may be examined. Teachers may use the site for explaining climate-related concepts, tying to local cities, or providing to students as a resource for further research.
Vocabulary:
- Insolation = a compilation of the words incoming solar radiation, referring to energy received by the Earth from the Sun
- Energy transfer = how energy moves from one place to another; three possible ways: radiation, conduction, or convection
- Radiation = transfer of radiant energy; travels through a vacuum as well as a medium
- Conduction = transfer of heat energy via direct contact between objects
- Convection = transfer of heat energy via the movement of fluids; cooler fluids contract becoming more dense and sink, while warmer fluids expand becoming less dense and rise
- Electromagnetic spectrum = all wavelengths of light including but not limited to) radio, microwave, infrared, visible, UV, X-rays, gamma rays
- Absorption = in this context, referring to the taking in of energy by an object; one of three ways that energy/light may interact with matter: absorption + reflection + transmission = 100%
- Reflection = in this context, referring to how incident energy/light is scattered off of an object
- Scattering = referring to how incident energy/light may be absorbed and re-emitted (or reflected) from an object
- Transmission = in this context, referring to how energy/light passes through an object
- Global warming = a general increase in the average global temperature of the planet (primarily related to changes in the Greenhouse effect)
- Greenhouse gas = any one of several gases present in Earth's atmosphere that strongly absorbs and re-emits infrared energy radiated by the Earth; contributes to the Greenhouse effect
Global climate animations are used as teaching tools in climatology and global environmental change courses to visualize the seasonal variations of, and interactions among a set of climate variables that describe the surface water and energy balances, temperature, and atmospheric circulation. (Benchmark 9.3.2.2.1)
At this Web site, explore scientific data relating to the atmosphere, the oceans, the areas covered by ice and snow, and the living organisms in all these domains. You'll also get a sense of how scientists study natural phenomena-how researchers gather evidence, test theories, and come to conclusions. (Benchmark 9.3.2.2.2)
This online simulator allows students to explore issues surrounding photochemical smog. By changing inputs, outputs can be examined; helps students to better understand smog and ties to chemistry.
Digital Library for Earth System Education:
A vast collection of resources for Earth Systems Science. Research by topic, grade level, and other to locate activities and informational resources. An excellent (and continually growing) reservoir.
A collection of carbon dioxide concentration to temperature graphs (going back 800,000 years). A resource for teachers to obtain information and graphs to be shared in classes.
UCAR.
Introductory information about the atmosphere and energy balance of the planet. Includes images, animations, and a list of activities for understanding atmospheric science.
Discovery News. (2011). [video clip] Earth: Signs of Climate Change in Alaska. Discovery Communications, LLC.
A video clip that discusses some early signs of global climate change in the delicate ecosystems of Alaska. Perfect for extending student interest into this topic.
Physical Science Connections:
Project 2061: Benchmarks for Science Literacy.
Chapter 4D- Structure of matter
By the end of the 12th grade, students should know that
The configuration of atoms in a molecule determines the molecule's properties. Shapes are particularly important in how large molecules interact with others. 4D/H8
Chapter 4E - Energy Transformations
As energy spreads out, whether by conduction, convection, or radiation, the total amount of energy stays the same. However, since it is spread out, less can be done with it. 4E/H3*
If no energy is transferred into or out of a system, the total energy of all the different forms in the system will not change, no matter what gradual or violent changes actually occur within the system. 4E/H10** (SFAA)
NSES Standards:
NSES Content Standard B Physical Science (grades 9-12)
Conservation of Energy and the Increase in Disorder
Everything tends to become less organized and less orderly over time. Thus, in all energy transfers, the overall effect is that the energy is spread out uniformly. Examples are the transfer of energy from hotter to cooler objects by conduction, radiation, or convection and the warming of our surroundings when we burn fuels.
Content Standard C Life Science (grades 9-12)
Matter, Energy, and Organization in Living Systems
The energy for life primarily derives from the sun. Plants capture energy by absorbing light and using it to form strong (covalent) chemical bonds between the atoms of carbon-containing (organic) molecules. These molecules can be used to assemble larger molecules with biological activity (including proteins, DNA, sugars, and fats). In addition, the energy stored in bonds between the atoms (chemical energy) can be used as sources of energy for life processes.
Other:
Radiation budget calculations tie to mathematics.
Length of geologic time ties to mathematics.
Earth as a system; how the biological element (e.g., adaptation, niches, mass extinctions, etc.) interacts with environmental characteristics of global climate change ties to Life Sciences.
The environmental chemistry related to the mechanisms of global climate change ties to Physical Sciences (chemistry).
Assessment
Students:
Bennett, J., Donahue, M., Schneider, N., & Voit, M. (2007). The cosmic perspective (4th ed.). San Francisco, CA: Pearson. [Chapter 10, p. 324; question 14; Answer from the associated "Instructor Guide" by same authors.]
1. Identify and describe four primary factors that can lead to long-term climate change on the Earth. [question modified]
Four primary factors are: solar brightening (the sun is getting brighter as it ages); the tilt of Earth's axis (currently 23.5 degrees, but varies, and affects the heating of particular regions of the planet); albedo (the overall reflectivity of the planet, dependent upon surface cover, cloud cover, presence of atmospheric dust, etc.); and abundance of greenhouse gases (increasing concentrations increases temperature). [answer modified from source]
Ahrens, C.D. (2008). Essentials of meteorology: An invitation to the atmosphere (5th ed.). Belmont, CA: Brooks/Cole. [Chapter 14, p. 412; Questions for Review 1, 14, 17, and Questions for Thought Exploration 1 respectively; answers from the associated "Instructor's Manual."]
2. What methods do scientists use to determine climate conditions that have occurred in the past?
The study of the geological evidence left behind by advancing and retreating glaciers; collection of fossil pollen of tundra plants; core samples taken from ocean floor sediments and Greenland and Antarctica ice; the study of annual growth rings of trees; documents concerning droughts, floods, and crop yields; the study of oxygen-isotope ratios of corals; borehole temperature profiles.
3. Describe some of the natural radiative forcing agents and their effect on climate.
Water vapor, via the water vapor-greenhouse effect feedback; solar irradiance changes; volcanic eruptions rich in sulfur.
4. Explain how the ocean's conveyor belt circulation works. How does the conveyor belt appear to influence the climate of northern Europe? [modified]
The conveyor-like circulation begins in the north Atlantic near Greenland and Iceland, where salty surface water is cooled through contact with cold Arctic air masses. The cold, dense water sinks and flows southward through the deep Atlantic Ocean, around Africa, and into the Indian and Pacific Oceans. In the North Atlantic, the sinking of cold water draws warm water northward from lower latitudes. As this water flows northward, evaporation increases the water's salinity (dissolved salt content) and density. When this salty, dense water reaches the far regions of the North Atlantic, it gradually sinks to great depths. This warm part of the conveyor delivers an incredible amount of tropical heat to the northern Atlantic. During the winter, this heat is transferred to the overlying atmosphere, and evaporation moistens the air. Strong westerly winds then carry this warmth and moisture into northern and western Europe, where it causes winters to be much warmer and wetter than one would normally expect for this latitude.
5. Ice cores extracted from Greenland and Antarctica have yielded valuable information on climate changes during the past few hundred thousand years. What do you feel might be some of the limitations in using ice core information to evaluate past climate changes?
The chemical concentrations retrieved from the water and air bubbles within ice cores may have undergone a variety post-depositional processes which can complicate their interpretation. These processes include chemical reactions, blowing and drifting, wind pumping (horizontal movement within the snowpack), freezing and thawing, and folding associated with subsurface glacial movement.
Teachers:
Ahrens, C.D. (2008). Essentials of meteorology: An invitation to the atmosphere (5th ed.). Belmont, CA: Brooks/Cole. [Chapter 14, p. 412, Questions for Review 8, 15, and Questions for Thought Exploration 3 respectively; and Chapter 13, p. 380, Questions for Thought Exploration 1; answers from the associated "Instructor's Manual."]
1. Given the analysis of air bubbles trapped in polar ice during the past 160,000 years, were CO2 levels generally higher or lower during colder glacial periods? Were methane levels higher or lower at this time?
Lower [for both].
2. Describe how clouds influence the climate system. Which clouds would tend to promote surface cooling: high clouds or low clouds?
Clouds reflect incoming sunlight back to space, a process that tends to cool the climate, but they also absorb infrared radiation from the earth, which tends to warm it. High clouds promote warming, low clouds promote cooling.
3. Consider the following climate change scenario. Warming global temperatures increase saturation vapor pressures over the ocean. As more water evaporates, increasing quantities of water vapor build up in the troposphere. More clouds form as the water vapor condenses. The clouds increase the albedo, resulting in decreased amounts of solar radiation reaching the earth's surface. Is this scenario plausible? What type(s) of feedback(s) is/are involved?
The effect of an increase in global cloudiness would probably depend upon the type and height of clouds that form. High, thin cirriform clouds would probably promote global warming (positive feedback) by allowing much of the incident sunlight to pass through them. At the same time, these cold clouds would radiate back to earth more infrared radiation than they would emit to space. Low stratified clouds would probably cool the planet (negative feedback) by reflecting much of the incident sunlight back to space. Also, their warm tops would radiate away much of the infrared energy that they receive from the earth.
4. Why do cities east of the Rockies, such as Denver, Colorado, get much more precipitation than cities east of the Sierra Nevada, such as Reno, Nevada?
Cities located east of the Rockies receive moisture from the Gulf of Mexico. The Rockies effectively block Gulf moisture from reaching cities located to the east of the Sierra Nevada Mountains. In addition, the Sierras shield the region east of them from Pacific moisture.
Administrators:
If observing a lesson on this standard what might they expect to see.
Students working with simulations, data, maps, or other activity-based lessons related to energy or climate. The instructor asks students to consider how the town in which they live affects the local climate. Students use the data they collected earlier (about temperature and different surface cover) to examine Google Earth images of their town and to make projections about the city temperature today relative to the possible temperature of the area before it was settled.
Differentiation
Struggling and At-Risk:
Include numerous activities for hands-on exploration (e.g., as discussed in the vignette) and tie into the real-world effects of climate change (i.e., increased diseases, decreased food supply, sea level rise) as they relate to current and future generations.
McGraw-Hill Education. (n.d.). Improving reading skills in science.
McGraw-Hill Education. (n.d.) Finding science in the real world.
McGraw-Hill Education. (n.d.) High stakes science tests: Will your students be ready?
For details, see:
According to Lee & Buxton (2010), a couple of approaches are useful for assisting English Language Learners (ELLs): teach content while fostering language development and draw on the so-called "funds of knowledge", which are students' personal experiences from home or community. For additional details on this see the original NSTA News posting and the official NSTA position statement.
Lee, O., & Buxton, C.A. (2010, April). NSTA Report: Teaching science to English language learners.
NSTA. (2004). Students with disabilities. Official NSTA Position Statement.
McGraw-Hill Education. (n.d.) English language learners in science.
G/T:
Retrieved from Differentiating Science Instruction. McGraw-Hill Education:
Differentiate assessment tools. Assessment does not always have to occur in a standardized format. Consider using alternative assessments, such as:
laboratory practicals
written opinions supported by data
verbal presentations
multimedia projects that target students with different learning preferences
Could be useful to investigate where the effects of global warming would be most noticeable and severe (in say 50 years, based on current projections). This would be a good way to tie into geography and social studies; students could be introduced to the cultures of some of these places (outside of North America).
For details see:
Multicultural science education. Official NSTA Position Statement. Retrieved from this page.