The dynamo theory states that earths magnetic field is created in the layer known as the core.
The thermosphere is a layer of the earth's atmosphere directly above the mesosphere and below the exosphere. It extends 56 miles to about 621 miles above the earth.
It is in the thermosphere that auroras are seen. An aurora is luminous atmospheric phenomenon appearing as streamers or bands of light sometimes visible in the night sky in northern or southern regions of the earth. It is thought to be caused by charged particles from the sun entering the earth's magnetic field and stimulating molecules in the atmosphere.
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Answer: B. global warming</h3>
As more CO2 (carbon dioxide) is released into the atmosphere, it traps more heat energy from the sun, and slowly warms the average temperature of the earth. This is the simplified version of what global warming is. Carbon dioxide is considered a greenhouse gas.
No Clean Water: We may live on a water planet, but 97.5% of that water is ocean and other undrinkable salt-filled sources. Only 2.5% of the water on this planet is fresh, and of that, 1% is either too polluted to be consumed or entirely unreachable. Much of it remains frozen in the form of polar ice caps. All told, less than 1% of the planet’s freshwater resources are available for consumption.
Lower Life Expectancy: Thanks to medical intervention, human beings can live to be up to 100 years old — as long as they live in developed countries where they have access to that medical care. One study, done by researchers at Harvard, found that the majority of population increases over the next 40 years or so will be in less developed countries.
Climate Change: We’ve been seeing the results of climate change firsthand in the dramatic weather patterns of 2017 — multiple category five hurricanes, dramatic wildfires and floods, and other atypical weather patterns that are threatening both lives and property.
The ability of an animal to maintain a stable internal environment is called homeostasis.