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Atmosphere, Climate, Energy, Hydrosphere, Weather



"Sunshine has returned to the capital following four days of dense fog in which London transport was brought to a standstill.

The atrocious conditions led to widespread disruption of rail, road and air services and affected shipping on the River Thames…

The fog, which began on 5 December, also affected other areas of the south-east, with icy roads causing several road accidents. Ambulance men and firemen had to walk ahead of their vehicles to reach those in need. " BBC report December 9, 1952

In the days and weeks following what came to be known as the Great Smog of 1952, at least 4000 people -- mostly elderly, very young, or those with respiratory disease -- died as a result of breathing in the fog. Other estimates tie as many as 12,000 deaths to the smog.

It had been very cold that early December and coal furnaces in London were belching out vast amounts of soot, tar particles, and sulfur dioxide. The concentration of sulfur dioxide, in the lower atmosphere, is estimated to have reached as much as seven times normal levels. When cold air, calm winds and high humidity conspired to create a dense fog, the sulfur dioxide trapped in the low-lying fog reacted with water vapor to produce sulfuric acid. The London fog had become a toxic smog - acid rain. Although sulfate-based smogs continue such as the 2006 smog that occurred in the Northeast U.S., Earth Observatory clean air acts and increasing emission controls in many developed countries have resulted in a great decrease in sulfate emissions.

Sulfur dioxide comes from both anthropogenic (related to human activities) and natural sources. Burning coal and other fossil fuels is the largest source of sulfur dioxide from human activities. Volcanoes and forest fires are the major natural contributors. Although sulfur dioxide is of interest as a pollutant, our primary emphasis here is to explore its role in climate change. Once in the atmosphere, sulfur dioxide can easily form sulfate ions, negatively charged particles made of up of sulfur and oxygen atoms. Because of their negative charge, sulfate ions readily combine with water vapor in the atmosphere to form small droplets of sulfuric acid (H2SO4).

When a volcano erupts huge amounts of sulfur dioxide are spewed into the stratosphere and converted to sulfates. Unlike sulfates formed at lower altitudes, which are removed from the atmosphere in just a few weeks through settling and precipitation, these aerosols (mainly tiny droplets of sulfuric acid) stay in the atmosphere for about two years. They reflect incoming solar radiation back into space,absorb both incoming solar radiation and outgoing infrared radiation thereby reducing the amount of energy reaching the lower atmosphere and Earth's surface. The net effect is a cooling of the lower atmosphere and Earth's surface.

Volcanic eruptions are thought to have considerable impact on global climate. Following the eruption of Mount Pinatubo in 1991, a cooling trend that lasted through 1993 was attributed to the sulfuric acid aerosols that persisted in the stratosphere. Similar cooling followed the 1883 eruption of Krakatoa and the "Year without a summer" followed the eruption of Tambora in 1815. The potential cooling effect of stratospheric sulfates is of great interest to scientists exploring possible geoengineering methods for climate intervention.

Many scientists believe the continuous emission of sulfates in the past offset the effects of increasing greenhouse gases, masking their warming effect. Today, with uneven concentrations of sulfates around the world, the effects on climate change are very complex. Rapidly developing countries like China and India are emitting increased amounts of sulfates, while western countries have greatly decreased their output. With increased sulfate production from these rapidly developing countries future worldwide concentration trends are uncertain.



Basic: Volcanic eruptions can inject large amounts of sulfates into the stratosphere, increasing the albedo of the Earth system. Your group's ESS analysis will provide policy makers information on the possible impact of several major volcanoes erupting over a five-year period.

One method that has been proposed to counter the effects of global warming is a geoengineering approach. By periodically injecting sulfates into the stratosphere, an effect -- much like that resulting from strong volcanic eruptions -- should occur. Your group has been approached by an environmental organization looking for a solution to global warming. They have requested an Earth System Science (ESS) analysis of this potential solution to global warming. If your analysis supports this approach, they are going to present a plan to the United Nations for implementation.

Note: Sulfur Dioxide data from NASA's OMI Aura is found here.
To learn how to use Giovanni see the provided demonstration. (This is a large file to download, but the demo provides a good look at some of Giovanni's capabilities.)


Date: 5/31/2011

Scenario Images:

Massive Air Pollution Event Highlights Sulfur Dioxide Trends in China
Visible imagery showing smog over Eastern China. NASA satellites revealed high concentrations of sulfur dioxide in the smog (

Sulfur Dioxide from Okmok VolcanoPosted July 25, 2008
Sulfur dioxide plume from Okmok volcano (Courtesy: NASA Earth Observatory) Click here for more information and larger view.

The Great London Smog of 1952
Picture taken during the Great London Smog of 1952 - coal burning resulted in much sulfur dioxide being input into the atmosphere
(Courtesy: Encyclopedia of Earth)



Atmospheric Aerosols: What Are They, and Why Are They So Important? (Cycle A)
Describes aerosols from volcanoes and the tropospheric cooling that occurred subsequent to the eruption of Mt. Pinatubo


Climactic Effects of the 1815 Eruption of Tambora (Cycle A)
The Tambora eruption in 1815 resulted in a temperature drop of 1 to 2.5 degrees Celsius in New England and the British Isles


Earth Observatory - Sulfur dioxide emissions, Bulgaria (Cycle A)
Describes sulfur dioxide emissions from a power plant in Bulgaria. See also this link for other sulfur dioxide emissions captured by NASA AIRS.


Impact of volcanic gases on climate, the environment, and people (Cycle A)
Describes the various gases emitted from volcanoes and their consequences.


Massive Air Pollution Event Highlights Sulfur Dioxide Trends in China (Cycle A)
Describes air pollution with sulfur dioxide as a component over China.


Quantifying tropospheric volcanic emissions with AIRS (comprehensive) (Cycle A)
In late October 2002, [NASA's] AIRS detected lower tropospheric sulfur dioxide and ash emitted by an eruption of Mt. Etna (Italy), in plumes which could be
tracked over 1000 km from the volcano into north Africa.


Windows to the universe - Sulfur dioxide and sulfur trioxide (Cycle A)
Describes how sulfur dioxide is oxidized to sulfur trioxide then reacts with water to form sulfuric acid.


Do clouds clean or clutter the air with sulfates? (Cycle B)
Describes the role of clouds in sulfate production and removal.


Global Warming and Climate Change - the science (Cycle B)
Discusses how the balancing effect of sulfates on greenhouse gases may be diminishing because of emission-control efforts.


Long range transport and fate of a stratospheric volcanic cloud (comprehensive) (Cycle B)
Author(s): Prata, A.J., Carn, S.A., Stohl, A., Kermann, J.
Periodical: Atmospheric Chemistry And Physics
Pub. Year: 2007
"Volcanic eruptions emit gases, ash particles and
hydrometeors into the atmosphere, occasionally reaching
heights of 20 km or more, to reside in the stratospheric over-
world where they affect the radiative balance of the atmo-
sphere and the Earth's climate."


Monitoring volcanoes from space (Cycle B)
Describes how NASA satellites monitor volcanoes from space.


Research News: Scientist Nadine Unger Discusses Which Sectors of the Economy Impact the Climate (Cycle B)
From NASA/GISS. Interview addresses how different economic sectors may affect climate. It looks at the role of sulfates in masking warming.


Sulfate aerosols and global warming (Cycle B)
Discusses the complex relationship between greenhouse gases and sulfates


Sulfur dioxide (Cycle B)
This EPA web site details the hazards of sulfur dioxide and its sources of emissions.


Sulfur Dioxide cuts may allow Increased Global Warming (Cycle B)
Describes the work of Michael Schlesinger on the production of sulfates in the atmosphere.


Volcanic Emissions and Global Cooling (Cycle B)
"This site provides information about the effects of carbon dioxide and sulfur dioxide volcanic emissions on global climate. Helpful diagrams depict the chemical processes involved in atmospheric cooling and historical examples are cited. The 1991 eruption of Mt. Pinatubo in used as a case study. The site also provides links to references cited and additional resources." See also the Enviropedia Site from the UK on the contribution of volcanic activity on climate.


For List of Classroom Lessons and Activities (Cycle C)
The Digital Library for Earth System Education is a valued resource for teaching about Earth as a system. This link is directly to sulfur dioxide materials.


Sample Investigations:


Criteria Pollutants (Cycle A)
Students collect air pollution information and organize them using a concept map.
Difficulty: beginner


The awful eight lesson plan (Cycle A)
Students put on a play about the EPA's six criteria pollutants (including sulfur dioxide) as well as Volatile Organic Compounds (VOCs)and CFCs.
Difficulty: beginner


Understanding global dimming (Cycle A)
Includes an interactive link that describes the role of aerosols including sulfates in offsetting global warming (5-12)
Difficulty: intermediate


What color is your sky? (Cycle A)
Students are asked to make a record of sky color to help them identify pollutants like sulfur dioxide and aerosols including sulfates.
Difficulty: beginner


Air pollution tragedy: A case study (Cycle B)
Students see the importance of various specialties in assessing pollution. (Sulfur dioxide was a main primary pollutant of the Great London Smog of 1952.)
Difficulty: intermediate


Climate Discovery Teacher's guide Lesson 8 (Cycle B)
Although not specifically mentioning sulfur dioxide, this Activity explores the role of aerosols from volcanoes in climate change.
Difficulty: intermediate


Mountain of Ice: Secrets in the Ice (Cycle B)
Students analyze actual ice core data and can examine historical concentrations od sulfates.
Difficulty: intermediate


Comparing sulfur dioxide concentrations (Cycle C)
In this investigation, students can compare the total column sulfur dioxide concentrations for different days.
Go to the NASA Giovanni A-train data web site. Select a date you are interested in then select total column SO2 for lower troposphere and boundary layer (the lowest 2,000 -3,000 feet of the atmosphere). - Then, generate the visualization. Repeat for another day and compare. Seasonal and annual variations in sulfur dioxide can be seen. Concentrations are in Dobson Units (DU).
One DU=0.01 millimeter
Difficulty: advanced


Local level SO2 data from WDGG (Cycle C)
Local level data from WDCGG (World Data Centre for Greenhouse Gases, regional level or local level at ground surface) This website is maintained by the Japan Meteorological Agency.
Follow the directions below to access the WDCGG data.
Log in WDCGG
From the left column choose Data/ Quick Plot
There are many options.
We must choose our parameters, including Gas Type, Data Type, Station Type, and Region. The parameters we will choose are as follows:
• Category: Stationary
• Parameter: SO2
• Country/Territory: Finland
There are several stationary ground stations collecting sulfur dioxide ground measurements
Choose the Ahtari, Finland Station to use data from. (There are no US stations on the list that collect SO2 data)
After this station has been selected, scroll down through the collected data types and select SO2.
From this menu we can see the SO2 data that the Ahtari Station has collected. There should be two columns in the main data sets: A data column and a quick plot column. Using the quick plot column we can view graphs of the SO2 data that has been collected. This data can be viewed as hourly, daily and monthly collection. Data source is the Finnish Meteorological Institute.
Difficulty: advanced




  • Science
    National Science Education Standards - Science Content Standards The science content standards outline what students should know, understand, and be able to do in the natural sciences over the course of K-12 education.
      The understandings and abilities associated with the following concepts and processes need to be developed throughout a student's educational experiences:
      • Systems, order, and organization
      • Evidence, models, and explanation
      • Constancy, change, and measurement
      • Science as Inquiry (Std A)
        • Abilities necessary to do scientific inquiry
        • Understanding about scientific inquiry
      • Physical Science (Std B)
        • Properties of objects and materials
      • Earth and Space Science (Std D)
        • Changes in earth and sky
      • Science and Technology (Std E)
        • Abilities to distinguish between natural objects and objects made by humans
      • Science in Personal and Social Perspectives (Std F)
        • Changes in environments
      • Science as Inquiry (Std A)
        • Abilities necessary to do scientific inquiry
        • Understanding about scientific inquiry
      • Physical Science (Std B)
        • Properties and changes of properties in matter
        • Transfer of energy
      • Earth and Space Science (Std D)
        • Structure of the earth system
      • Science and Technology (Std E)
        • Understanding about science and technology
      • Science in Personal and Social Perspectives (Std F)
        • Natural hazards
        • Risks and benefits
      • History and Nature of Science (Std G)
        • Science as a human endeavor
        • Nature of science
      • Science as Inquiry (Std A)
        • Abilities necessary to do scientific inquiry
        • Understanding about scientific inquiry
      • Physical Science (Std B)
        • Structure and properties of matter
        • Chemical reactions
        • Interactions of energy and matter
      • Life Science (Std C)
        • Matter, energy, and organization in living systems
      • Earth and Space Science (Std D)
        • Energy in the earth system
        • Geochemical cycles
      • Science and Technology (Std E)
        • Understanding about science and technology
      • Science in Personal and Social Perspectives (Std F)
        • Natural resources
        • Environmental quality
        • Natural and human-induced hazards
      • History and Nature of Science (Std G)
        • Nature of scientific knowledge
  • Mathematics
    Principles and Standards for School Mathematics, National Council of Teachers of Mathematics (NCTM), 2000 This set of Standards proposes the mathematics concepts that all students should have the opportunity to learn. Each of these ten Standards applies across all grades, prekindergarten through grade 12. Even though each of these ten Standards applies to all grades, emphases and expectations will vary both within and between the grade bands (K-2, 3-5, 6-8, 9-12). For instance, the emphasis on number is greatest in prekindergarten through grade 2, and by grades 9-12, number receives less instructional attention. Also the total time for mathematical instruction will be divided differently according to particular needs in each grade band - for example, in the middle grades, the majority of instructional time would address algebra and geometry.
      Mathematics instructional programs should include attention to patterns, functions, symbols, and models so that all students—
      • use symbolic forms to represent and analyze mathematical situations and structures;
      • use mathematical models and analyze change in both real and abstract contexts.
      Mathematics instructional programs should include attention to geometry and spatial sense so that all students—
      • use visualization and spatial reasoning to solve problems both within and outside of mathematics.
      Mathematics instructional programs should include attention to data analysis, statistics, and probability so that all students—
      • pose questions and collect, organize, and represent data to answer those questions;
      • interpret data using methods of exploratory data analysis;
      • develop and evaluate inferences, predictions, and arguments that are based on data;
      Mathematics instructional programs should focus on solving problems as part of understanding mathematics so that all students—
      • build new mathematical knowledge through their work with problems;
      • develop a disposition to formulate, represent, abstract, and generalize in situations within and outside mathematics;
      • apply a wide variety of strategies to solve problems and adapt the strategies to new situations;
      • monitor and reflect on their mathematical thinking in solving problems.
      Mathematics instructional programs should use communication to foster understanding of mathematics so that all students—
      • organize and consolidate their mathematical thinking to communicate with others;
      • express mathematical ideas coherently and clearly to peers, teachers, and others;
      • extend their mathematical knowledge by considering the thinking and strategies of others;
      Mathematics instructional programs should emphasize connections to foster understanding of mathematics so that all students—
      • recognize, use, and learn about mathematics in contexts outside of mathematics.
  • Geography
    Geography for Life: National Geography Standards, 1994
      Geography studies the relationships between people, places, and environments by mapping information about them into a spatial context. The geographically informed person knows and understands:
      • How to use maps and other geographic representations, tools and technologies to acquire, process, and report information from a spatial perspective
      • How to analyze the spatial organization of people, places, and environments on Earth’s surface
      Physical processes shape Earth’s surface and interact with plant and animal life to create, sustain, and modify ecosystems. The geographically informed person knows and understands:
      • The physical processes that shape the patterns of Earth’s surface
      People are central to geography in that human activities help shape Earth’s surface, human settlements and structures are part of Earth’s surface, and humans compete for control of Earth’s surface. The geographically informed person knows and understands:
      • The characteristics, distribution, and migration of human populations on Earth’s surface
      • The patterns and networks of economic interdependence on Earth’s surface
      The physical environment is modified by human activities, largely as a consequence of the ways in which human societies value and use Earth’s natural resources, and human activities are also influenced by Earth’s physical features and processes. The geographically informed person knows and understands:
      • How human actions modify the physical environment
      • How physical systems affect human systems
      Knowledge of geography enables people to develop an understanding of the relationships between people, places, and environments over time — that is, of Earth as it was, is, and might be. The geographically informed person knows and understands:
      • How to apply geography to interpret the present and plan for the future
  • Technology
    The International Society for Technology Education From and
      • Students are proficient in the use of technology.
      • Students practice responsible use of technology systems, information, and software.
      • Students use technology tools to enhance learning, increase productivity, and promote creativity.
      • Students use technology to locate, evaluate, and collect information from a variety of sources.
      • Students use technology tools to process data and report results.
      • Students evaluate and select new information resources and technological innovations based on the appropriateness for specific tasks.
      • Students use technology resources for solving problems and making informed decisions.
      • Students employ technology in the development of strategies for solving problems in the real world.
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