Question: How fast does the sun travel around the center of the galaxy?
Correct Answer Although it takes more than 10,000,000 years for the sun to make one circuit of the galaxy, the galaxy is so large that it must travel at almost 150 miles/second to cover the distance in that time.
Correct Answer A brown dwarf is a star-like body that is too light to have enough density in its center to transform hydrogen into helium. It may transform lithium, beryllium, and boron that can be transformed at lower temperatures and densities. The difference between a brown dwarf and a planet is harder to define observationally. Normally, it is considered that a planet is created by the accretion of material around a star that has already formed. A brown dwarf can form independently of another star.
Question: Which phenomenon of global warming in the Pacific Ocean will also likely increase in frequency and severity as long-term global warming continues?
Correct Answer El Nino is the warming of the surface waters of the Pacific Ocean to the north of the Equator. In the past, the appearance of the El Nino has caused unusual weather extremes, especially with respect to precipitation, in many areas around the world.
Question: A global warming trend that disrupts the normal current flows in the North Atlantic will likely result in cooler conditions for which continent?
Correct Answer The nations of western and central Europe experience relatively mild conditions for their latitudes due to the warmth brought in by the Gulf Stream. Any disruption of the Gulf Stream will reduce its temperate influence on western and central Europe, providing an example of regional cooling that will occur in a global warming trend.
Question: Melting ice in the Arctic will have a steady volume of cold freshwater coming into the North Atlantic will disrupt the flow of which well-known ocean current?
Correct Answer The Gulf Stream is a warm ocean current that flows northeastward from the southeastern US coast towards western Europe. The intrusion of cold water from the melting Arctic ice cap may divert this current southward, disrupting its influence on Europe.
Question: Global warming will have an adverse effect on the polar ice caps. What is the most important reason why melting polar ice caps is such a major concern in the long term?
Correct Answer Icebergs certainly pose a risk to shipping concerns, and reduced hunting ranges for polar bears and increased oil exploration are certainly ecological concerns. However, melting polar ice caps can raise the world's ocean level by several feet, inundating many island nations as well as some very heavily populated coastal areas on many continents.
Question: The increase in heat energy being retained by the planet will entail more frequent and stronger atmospheric disturbances. We should therefore see this type of storm become more common and/or more violent:
Correct Answer Hurricanes, willy-willies, and typhoons are the names tropical cyclones are called in different parts of the world. All tropical cyclones are essentially heat engines that take in energy from the ocean's surface and dissipate that energy in the upper levels of the atmosphere. Global warming will generally tend to increase the frequency and/or the severity of tropical cyclones.
Question: Of the following peoples, who are *currently* being affected the most by increasing temperatures?
Correct Answer Again, the clearest sign of long-term warming is being detected in the polar regions. This is especially true in the Arctic, where many indigenous peoples have built a way of life around the challenging frigid conditions. This way of life is now being affected. However, if trends continue, all peoples of the world will be affected by global warming.
Question: Where are some of the clearest, most early signs of a global warming phenomenon being observed?
Correct Answer Temperatures around the Equator remain relatively stable, regardless of the time of year, and conditions there continue to be stable. However, it is at the poles where a long-term warming trend is being observed most clearly. In addition to weather observations, shrinking polar ice caps and anecdotal evidence from indigenous peoples of the Arctic point to unmistakable climate change.