Basics
Climate Change refers to any significant change in weather (temperature, precipitation, etc.) over an extended period of time.
Global Warming refers to the recent and ongoing rise in the average temperature around the world near Earth’s surface.
Earth’s climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7000 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives. However, the current warming trend is of particular significance because most of it is very likely human-induced and proceeding at a rate that is unprecedented in the past 1300 years. — NASA
Global Warming is caused mostly by increasing concentrations of carbon dioxide and other gases in the atmosphere. These “greenhouse gases” trap energy in the atmosphere and cause it to warm. Over the past half-century, human activities, particularly the burning of fossil fuels to produce energy, have, in turn, produced greenhouse gases. Other human activities (deforestation, industrial processes, agricultural practices) have also emitted greenhouse gases into the atmosphere. The resultant global warming is causing climate patterns to change. — Environmental Protection Agency
Climate Change is an enormous subject, encompassing social studies, science, and many other areas.
As per climate.nasa.gov, what follows is a brief outline highlighting some of the issues associated with climate change.
Carbon Dioxide (CO2)
Carbon dioxide levels are at their highest in 650,000 years. As noted above, the burning of fossil fuels (oil, gas, coal) has been the main cause of ↑CO2. Deforestation (e.g. cutting down trees in the Indonesian and Brazilian rainforests) worsens the problem, because plants naturally remove CO2 from the atmosphere through the carbon sequestration process of photosynthesis.
Ocean acidification (which harms marine life through oceanic carbon sequestration) is also related to the increase in atmospheric CO2.
Acid rain (highly acidic precipitation harming vegetation, surface water, and soil) and smog (urban air pollution) are related to the increased production of such other greenhouse gases as sulfur dioxide and nitrogen oxide.
Temperature
Global temperatures have increased approximately 2.0 °F (1.0 ºC) over the last 150 years.
As Earth has become trapped in its own greenhouse gases, other phenomena attributed to global warming include drought, wildfires, melting arctic ice, melting land ice, and rising sea levels.
Polar Ice
Ice in both the North and South Poles has been melting.
Land Ice
Land ice, in the form of sheets, glaciers, and snow cover, has been diminishing.
Sea Level
Global sea level has risen steadily over the past hundred years. Certainly, the melting of polar and land ice has contributed to this rise. The ocean itself has warmed over time, too.
Practice – Questions
1. The above graph from the National Oceanic & Atmospheric Administration shows the trend in carbon dioxide (CO2) levels over the ocean over time. The black line represents average CO2 levels and the red line represents monthly CO2 levels. Based on the black line graph, how did average CO2 levels change (in parts per million) from the beginning of 2010 to the beginning of 2015?
A. from 397 to 399
B. from 377 to 399
C. from 400 to 399
D. from 387 to 399
2. What might account for the periodic upward rises in the red line graph?
A. Increased CO2 from increased solar panel emissions.
B. Decreased CO2 from increased solar panel emissions.
C. Increased CO2 from increased winter power plant emissions.
D. Decreased CO2 from increased winter power plant emissions.
3. The above graph from NASA shows the trend in global temperature over time. Based on the graph, in which year was the 5-year mean temperature the lowest?
A. 2010
B. 1880
C. 2000
D. 1910
4. Based on the graph, what theoretically could have accounted for the temporary spike in 5-year mean temperature around 1942?
A. Increased consumer purchases of silk stockings.
B. Decreased sales of war bonds.
C. Increased worldwide armament factory CO2 emissions during World War II.
D. Decreased worldwide armament factory CO2 emissions during World War II.
5. The above graph from NASA shows the trend in arctic sea ice coverage over time. Based on the graph, in what year was artic sea ice at its most expansive?
A. 1996
B. 2012
C. 2004
D. 2000
6, Based on the graph, in what year was arctic sea ice at its least expansive?
A. 1996
B. 2012
C. 2004
D. 2000
7. The above side-by-side histograms from NASA show trends in deforestation in Indonesia and Brazil. Based on the histograms, in which country has deforestation increased?
A. Lilliput
B. Oz
C. Brazil
D. Indonesia
8. Based on the histograms, in which country has deforestation decreased?
A. Lilliput
B. Oz
C. Brazil
D. Indonesia
9. The above graph from NASA shows the trend in coastal sea level over time. Based on the graph, how did the coast sea level change (in mm) from the beginning of 1870 to the beginning of 1970?
A. from 2 to 175
B. from 50 to 175
C. from -2 to 175
D. from -50 to 175
10. Based on the graph, which of the following years would have been best for an astronaut orbiting in a space capsule to return to Earth by plopping into the sea?
A. 1950
B. 1952
C. 1961
D. 1951
Practice – Answers
1. D. from 387 to 399
2. C. Increased CO2 from increased winter power plant emissions.
3. D. 1910
4. C. Increased worldwide armament factory CO2 emissions during World War II.
5. A. 1996
6. B. 2012
7. D. Indonesia
8. C. Brazil
9. C. from -2 to 175
10. C. 1961