Question 1

Scientists have developed a number of geo-engineering approaches to limit incoming solar radiation, which would then cool the planet. One of the ideas is to launch enormous orbiting mirrors or reflective shields to limit the amount of incoming solar radiation. Is this a reasonable idea? Other than costs associated with building and launching such a device, can you think of any other inherent risks or issues with such an undertaking?

Accepted Answer

While the idea of launching enormous orbiting mirrors or reflective shields to limit incoming solar radiation may seem like a potential solution to cool the planet, there are several inherent risks and issues associated with such an undertaking.

Firstly, the environmental and ecological impacts of manipulating incoming solar radiation on a large scale are not fully understood. It is possible that altering the amount of solar radiation reaching the Earth could have unintended consequences on weather patterns, ecosystems, and agriculture.

Additionally, the deployment and maintenance of such a large-scale geo-engineering project would require significant resources and international cooperation. The costs associated with building and launching the necessary devices would be substantial, and there would likely be political and logistical challenges in coordinating such a global effort.

Furthermore, there are potential ethical concerns surrounding the idea of deliberately manipulating the Earth's climate. The long-term effects of such geo-engineering approaches are uncertain, and there is a risk of creating further environmental imbalances or exacerbating existing climate issues.

In conclusion, while geo-engineering approaches such as launching orbiting mirrors or reflective shields may offer a potential solution to limit incoming solar radiation and cool the planet, the inherent risks and issues associated with such an undertaking must be carefully considered before pursuing such a solution. It is essential to thoroughly evaluate the potential environmental, economic, and ethical implications before implementing large-scale geo-engineering projects.

Question 2

How is the concept of the ecological footprint related to that of carrying capacity?

Accepted Answer

The concept of the ecological footprint is related to the concept of carrying capacity in that both concepts are measures of the impact of human activity on the environment. The ecological footprint measures the amount of biologically productive land and water area required to produce the resources a population consumes and to absorb its waste, while the concept of carrying capacity refers to the maximum population size that an environment can sustain indefinitely.

The ecological footprint helps to illustrate the demands that human populations place on the Earth's resources, while carrying capacity helps to determine the Earth's ability to support those demands. By comparing the ecological footprint of a population to the carrying capacity of the environment, we can assess whether the population is living within the means of the environment or exceeding its capacity to support them.

In this way, the ecological footprint and carrying capacity are closely related as they both provide valuable information about the sustainability of human activity and its impact on the environment. By understanding and considering these concepts, we can work towards living within the Earth's means and ensuring the long-term health of our planet.

Question 3

By 1914, at the beginning of World War I, the abundance of Bowhead whales decreased from 50,000 to about __________ .

Accepted Answer

3,000

Question 4

One way to quantify the human impact on Earth systems and to explore interactions among population, lifestyle, technology, and the environment is the ___________ equation.

Accepted Answer

The answer of One way to quantify the human impact...

Question 5

One way for decision makers to deal with risk is to rely on the ____________ principle, the concept that if the potential consequences of an event are unacceptably severe, those in authority have a responsibility to take action.

Accepted Answer

The answer of One way for decision makers to deal...

Question 6

____________is the expansion of desert conditions into previously productive land areas.

Accepted Answer

The answer of ____________is the expansion of desert conditions into...

Question 7

Mining, road construction, and other earth-moving activities contribute dramatically to exposure and ultimately erosion of ___________ .

Accepted Answer

The answer of Mining, road construction, and other earth-moving activities...

Question 8

As the __________ has grown and become more industrialized, people have altered the natural flow of rivers and released ever-larger amounts of waste.

Accepted Answer

The answer of As the __________ has grown and become...

Question 9

Surface water reservoirs in industrial areas are susceptible to ___________ pollution -- the release of heat or heated water (which is harmful to aquatic organisms and ecosystems).

Accepted Answer

The answer of Surface water reservoirs in industrial areas are...

Question 10

An algal __________ can occur when an aquatic system is overloaded with nutrients.

Accepted Answer

The answer of An algal __________ can occur when an...

Question 11

As __________rise into the upper atmosphere, ultraviolet radiation breaks them down, releasing chlorine in the form of chlorine monoxide.

Accepted Answer

The answer of As __________rise into the upper atmosphere, ultraviolet...

Question 12

At present, forests are experiencing the greatest impacts from clear-cut logging and other forms of land clearing.

Accepted Answer

The answer of At present, forests are experiencing the greatest...

Question 13

The United Nations Food and Agriculture Organization reports that __________ percent of the world's fish stocks are now fully exploited, overexploited, or depleted.

Accepted Answer

The answer of The United Nations Food and Agriculture Organization...

Question 14

The __________ effect results from the absorption of outgoing heat from Earth's surface by radiatively active gases in the atmosphere, such as carbon dioxide, methane, and water vapor.

Accepted Answer

The answer of The __________ effect results from the absorption...

Question 15

A __________ atmosphere will lead to increased evaporation from oceans, lakes, and streams.

Accepted Answer

The answer of A __________ atmosphere will lead to increased...

Question 16

___________ gas absorbs infrared radiation 25 times more efficiently that carbon dioxide.

Accepted Answer

The answer of ___________ gas absorbs infrared radiation 25 times...

Question 17

___________ have been successful in simulating the general character of present-day climates and have greatly improved weather forecasting.

Accepted Answer

The answer of ___________ have been successful in simulating the...

Question 18

The burning of fossil fuels and the clearing of forested land cause __________ to move from the geosphere and the biosphere to the atmosphere.

Accepted Answer

The answer of The burning of fossil fuels and the...

Question 19

Scientists estimate that in the past 200 years the rate of species __________ has soared to thousands per decade.

Accepted Answer

The answer of Scientists estimate that in the past 200...

Question 20

__________ reefs are formed by colonies of tiny animals which coexist in a symbiotic relationship with photosynthetic algae.

Accepted Answer

The answer of __________ reefs are formed by colonies of...

Quiz 19: The Changing Earth System