Lab 3: Residence Time Distribution and System Circulation

What method of waste disposal is best for the climate?

All waste disposal methods release greenhouse gases, and it’s hard to make apples-to-apples comparisons. But there’s only one solution that doesn’t contribute to climate change at all: not making waste in the first place.

Has there been climate change before?

The Earth’s climate is always changing, but human-caused climate change today is unlike any other period in our planet’s history

Could Snowpiercer actually happen?

Not accidentally—there would need to be deliberate efforts over many generations to get an ice-covered Earth. But geoengineering to reduce the risks of climate change does pose other risks that are much more probable than the ones shown in Snowpiercer

I know that if we stop burning fossil fuels, it will reduce carbon emissions. But are there other benefits as well?

Reducing fossil fuel use is not just a long-term investment to slow climate change—it also protects human health and environmental ecosystems, saving lives almost immediately.

How do greenhosue gases trap heat in the atmosphere?

Greenhouse gas molecules in the atmosphere absorb light, preventing some of it from escaping the Earth. This heats up the atmosphere and raises the planet’s average temperature.

How efficient is carbon capture and storage?

Most carbon capture technologies aim to stop at least 90% of the CO₂ in smokestacks from reaching the atmosphere. But as the technology approaches 100% efficiency, it gets more expensive and takes more energy to capture additional CO₂.

Why aren’t we looking at more hydropower?

Hydropower is already a major source of power globally—it’s the largest source of renewable electricity and one of the fastest growing—but there are limited places to build hydropower, and large dams carry a number of social and environmental concerns.

How are countries held accountable under the Paris Agreement?

The short answer is that there is no hard enforcement in the Paris Agreement. But all the members regularly meet, share progress, and renew their pledges of climate action, encouraging every country to step up its commitments.

Why have I heard that eating meat is bad for the climate?

Meat directly produces greenhouse gas emissions and requires more land and other resources than plant-based foods.

Is there a place in the atmosphere where carbon dioxide is concentrated, and if so, can we remove it?

Carbon dioxide mixes evenly through the atmosphere. But the atmosphere as a whole is densest near the ground, so a cubic foot of air at ground level will contain more carbon dioxide molecules than a cubic foot of air high up in the sky.