Answer:
B. Convection
D. Conduction
Explanation:
Conduction and convection are the two most prominent processes that helps transfer energy outward to the earth's crust.
- Energy within the core is a function of the radioactive decay and frictional heating.
- Also, heat that accreted during the formation of the earth is a significant source of internal energy.
- The heat is conducted away by the process of convection. This is possible due to temperature differences between different parts of the earth
- Conduction is made made possible due to the metallic bodies in the core and other part of the inner earth.
Answer: The level of CO2 has risen.
Explanation:
From the table shown, we can see that the quantity of CO₂ in the atmosphere has steadily risen since the year 1960 going from 317 CO₂PPM in that year to 390 CO₂PPM in 2010.
This is a cause for alarm because with so much carbon dioxide in the atmosphere, there will be an even greater greenhouse effect that will contribute to global warming.
Scientists have been observing Earth for a long time. They use NASA satellites and other instruments to collect many types of information about Earth's land, atmosphere, ocean and ice. This information tells us that Earth's climate is getting warmer.
Extra:
Extra greenhouse gases in our atmosphere are the main reason that Earth is getting warmer. Greenhouse gases, such as carbon dioxide (CO2) and methane, trap the Sun's heat in Earth's atmosphere.
It's normal for there to be some greenhouse gases in our atmosphere. They help keep Earth warm enough to live on. But too many greenhouse gases can cause too much warming.
The burning of fossil fuels like coal and oil increase the amount of CO2 in our air. This happens because the burning process combines carbon with oxygen in the air to make CO2.
It's important that we monitor CO2 levels, because too much CO2 can cause too much warming on Earth. Several NASA missions have instruments that study CO2 in the atmosphere.
A heat pump is a device that puts out heat. It involves pumping a lever over and over to get energy so it can work.