A polar vortex is an area of a. high-pressure wind b. low-pressure wind c. high-temperature wind
The polar vortexes a. appear only during the winter b. appear every seven years c. are always there
When the polar winds weaken, temperate regions will likely experience a. warmer winters b. warmer summers c. colder winters
Discussion/essay questions
Has your region experienced any effects of climate change? What are leaders doing about it? Do you think they should be doing more? Why or why not?
Transcript
A polar vortex is an area of low-pressure wind that circulates at the Earth’s poles. The winds of a polar vortex are very high in the atmosphere, and they contain some of the Earth’s coldest air. The northern and southern vortexes are always there, but changes in the winds can affect temperatures around the world. When the winds weaken, they affect lower belts of air called polar jet streams. If a polar vortex is not strong enough to hold the winds in place, the jet stream can grow wide and irregular. Unusually cold winters can happen when jet streams spread cold polar air to more temperate regions. It is possible that climate change will affect the polar vortex by weakening the polar winds over time. This could change the way that many regions experience seasons and create new extreme weather patterns, both hot and cold.
The corona is a. 300 times cooler than the surface of the Sun b. 300 times hotter than the surface of the Sun c. 300 times cooler than the surface of the Earth
On Earth, coronal mass ejections can cause a. severe storms b. extremely high temperatures c. damage to the power grid
The corona is only visible during a. a CME b. a solar flare c. a total solar eclipse
Discussion/essay questions
In 1859, a CME caused telegraph stations around the world to burn out. Because we depend so much on technology, a CME of the same size today would cause major damage. What do you think the world would be like without any modern technology?
Transcript
The outer atmosphere of the Sun is called the corona. It is a thin layer of charged gas that extends for millions of kilometres. It is actually about 300 times hotter than the Sun’s surface, which is an ongoing puzzle for scientists. The corona is a chaotic environment, and it sometimes releases large amounts of magnetic matter into space. This is called a coronal mass ejection, or CME. Scientists monitor CMEs because they can damage the power grid on Earth. Most of the time, the corona is impossible to see with the naked eye. The surface of the Sun is so bright that it completely outshines the light from the outer layers. However, the corona can be seen briefly during a total solar eclipse, when the Moon obscures the Sun from view.
El NiƱo is caused by a. human activity b. hurricanes c. weakened winds
During El NiƱo events, warmer winters occur a. in the north b. in the south c. globally
La NiƱa is the name for a. changes in air pressure in El NiƱo years b. a strong type of hurricane over the Atlantic c. the reverse effect to El NiƱo
Discussion/essay questions
El NiƱo is a natural phenomenon unrelated to global climate change. However, some scientists predict that El NiƱo events may become more extreme as temperatures continue to rise. Have you experienced weather changes where you live? What do they look like?
Transcript
El NiƱo is part of a natural weather pattern that begins in the Pacific Ocean. It happens when the west-travelling winds across the ocean grow weaker, causing surface waters to warm up in the east. This can affect ecosystems, storms, and temperatures around the world. During El NiƱo years, many northern places experience warmer winters. South American fishermen named the effect “El NiƱo,” or “the little boy,” after Jesus Christ, because they often observed changes in water temperature before Christmas. El NiƱo also has a reverse effect, called La NiƱa, which causes colder winters in the north and stronger hurricanes over the Atlantic. The full name that scientists use for the phenomenon is El NiƱo/Southern Oscillation, or ENSO. The Southern Oscillation is the change in air pressure connected to El NiƱo and La NiƱa. El NiƱo and La NiƱa events happen every two to seven years on average.
The ozone layer absorbs a. visible light b. ultraviolet radiation c. debris from space
Ozone is made up of a. bonded oxygen atoms b. bonded oxygen and chlorine atoms c. bonded oxygen and carbon atoms
The “hole” in the ozone layer is above a. Australia b. North America c. Antarctica
Discussion/essay questions
The quick action taken in 1987 prevented a global disaster. Do you think the world will be able to prevent climate change the same way?
Transcript
The ozone layer is a layer of gas in the Earthās atmosphere that absorbs ultraviolet radiation from the Sun. The molecules that make up ozone gas are made of three bonded oxygen atoms. Ozone forms when photons break up molecules of oxygen gas. The ozone layer protects humans and animals from the harmful effects of UV radiation, including cancers. However, in the 1980s, scientists discovered a dangerously thin area in the ozone layer above Antarctica. This is commonly known as the āozone holeā. Artificial emissions of chlorine gases had destroyed many of the ozone molecules in the atmosphere. In 1987, a global agreement known as the Montreal Protocol banned the use of certain chemicals in order to protect the ozone layer. Since then, the ozone hole has been shrinking.
Can you see auroras where you live? Would you ever travel to see them?
Transcript
Auroras are bright lights that appear in the sky over the North and South Poles. They are commonly known as northern and southern lights. Auroras occur when particles of plasma shoot out of the sun and collide with gases in the Earthās atmosphere. Different types of gas can create different colours of light. Oxygen creates green light, while nitrogen creates violet light. Auroras on other planets often have different colours because of the different gases that are common in their atmospheres. On gas giants like Jupiter and Saturn, auroras are ultraviolet. Although auroras are nice to look at, they can also be dangerous. The solar particles can cause damage to technology on Earth. Scientists hope to learn more about auroras so that they can prevent possible problems in the future.
Human fossil fuel use is a big issue. Carbon dioxide levels are getting higher, and climate change is going to affect the world in many ways. Are there any changes you’ve made in your life to help the environment? Are there changes you’d like to make in the future?
Transcript
Carbon dating is a process that scientists use to find out the age of a fossil. All living things consume forms of carbon throughout their lives. A rare type of carbon called carbon-14 is radioactive, which means that it decays over time. Living things usually absorb carbon-14 through natural carbon dioxide in the atmosphere. Since every radioactive substance decays at a specific rate, scientists can use a substanceās half-life to find out how long it has existed. Carbon-14 has a half-life of 5700 years. Scientists can estimate an age for any fossil that has enough carbon-14 left to measure. However, carbon dating may become more difficult as humans continue to use fossil fuels. Oil and coal put more stable carbon dioxide into the atmosphere, which affects the amount of carbon-14 that living things absorb. If a plant or an animal does not contain enough carbon-14 to measure, then finding its age will be much harder.