Category: Blog Posts

by Hannah Back

1.5°C Lifestyles

In the previous post, I discussed where carbon dioxide (the primary greenhouse gas causing climate change) is coming from. We learned that 85% of US emissions come from households.

Is there anything we can do to reduce our fossil fuel use, on a household level?

Greener lifestyles could be key in fighting climate change.

Some climate scientists believe we can save immense amounts of carbon through “behavioral mitigation”, by just making lifestyle changes¹. There is an idea of a “1.5 degree lifestyle”, which is a hypothetical lifestyle that is compatible with limiting warming to 1.5 degrees Celsius (the estimated level of warming that will limit critical effects)².

Reducing our consumption could help us avoid the worst of global warming. Consumers would have to make different choices, and government policies could help support those lifestyle changes (including promoting things like public transit)³.

How much do we have to change?

Let’s look at the numbers. Each American household causes about 21.2 tonnes (t) of carbon dioxide emissions per year.

That breaks down into different categories of consumption: Transportation, residential shelter, food, and good/services⁴.

These larger categories are broken down further. For example, most of “transportation emissions” are driven by car’s tailpipe emissions (driving directly releases greenhouse gases as fuel is burned). In our homes, a large amount of the carbon emissions is from heating and cooling. For food related emissions, beef and dairy have a large impact. 

One scientist estimated the “carbon savings” from different lifestyle changes. He quantified the impact from different levels of lifestyle change, from “minimal”, to “moderate” and “ambitious” changes⁴.

He found that even “minimal changes” could have a huge impact! Minimal changes included driving and flying less, raising or lowering thermostat, switching to LED lights, reducing hot water use and spending less money on products that cost carbon to manufacture and transport.

Reducing household electrical use can save 1.2 tonnes of CO2e per year.

In the “minimal changes”, one change people would have to make is reducing beef intake by 50%, which may be hard for some to swallow. Beef has a particularly high carbon impact because of the land use and feed required to raise cattle.

Driving and flying less can save 1.4 tonnes of CO2e per year.

However, there are other ways to make changes! If someone has difficulty cutting back in one area, they could look at other categories that may be easier for them to reduce. For example, living in a college town, I can cut back my driving to nearly zero because of great public transportation. Others may struggle with lack of transit available.

Some people may be more agreeable to adjusting their thermostat and reducing energy use in the home, or even installing solar panels with the help of federal incentives. Some people may have considered eating less meat before, and to them, this could be an easy change. Some people find it easier to reduce spending. People should look at different areas of their lifestyle and consider what changes they would be most willing to enact.

With small changes, you can save almost 5 tonnes of CO2e per year.

If people are willing to make “moderate” changes, their CO2e impact can be reduced to almost half⁴.

Towards Greener Lifestyles

First, we should work to educate on the impact of lifestyle choices. Then, people can be empowered to choose what changes work best for them and their family. People’s choices also tend to impact those around them.

Of course, some people may find it difficult to make changes, or unwilling to do so. Despite this, our own choices still matter. Once carbon dioxide is released, it cannot be captured. The best answer we have is to prevent more emissions in the first place.

Every bit counts towards keeping us “in the green” on the carbon budget⁵ – a budget calculated by scientists to measure how much carbon can still be released while avoiding the most severe effects. Current estimates show only about 100 gigatonnes for an 83% chance of staying under 1.5 degrees Celsius of warming⁶. So, every bit of carbon we release takes away from this budget.

In conclusion, household consumption drives emissions, which drives climate change. The only way to stop climate change is by stopping emissions. Therefore, the choices you and I make in our daily lives are crucial in the battle against climate change. 

Don’t let perfect be the enemy of the good—Make what changes you can and encourage those around you!

References

[1] R. Koide, M. Lettenmeier, L. Akenji, V. Toivio, A. Amellina, A. Khodke, A. Watabe, S. Kojima, Lifestyle carbon footprints and changes in lifestyles to limit global warming to 1.5 °C, and ways forward for related research, Sustain Sci 16 (2021) 2087–2099. https://doi.org/10.1007/s11625-021-01018-6.

[2] IPCC, 2018: Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [V. Masson-Delmotte, P. Zhai, H. O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J. B. R. Matthews, Y. Chen, X. Zhou, M. I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, T. Waterfield (eds.)]. In Press.

[3] G. Dubois, B. Sovacool, C. Aall, M. Nilsson, C. Barbier, A. Herrmann, S. Bruyère, C. Andersson, B. Skold, F. Nadaud, F. Dorner, K.R. Moberg, J.P. Ceron, H. Fischer, D. Amelung, M. Baltruszewicz, J. Fischer, F. Benevise, V.R. Louis, R. Sauerborn, It starts at home? Climate policies targeting household consumption and behavioral decisions are key to low-carbon futures, Energy Research & Social Science 52 (2019) 144–158. https://doi.org/10.1016/j.erss.2019.02.001.

[4] S.E. Eikenberry, A fair share: doing the math on individual consumption and global warming, 2018.

[5] Carbon budget, Wikipedia (2024). https://en.wikipedia.org/w/index.php?title=Carbon_budget&oldid=1216099389.

[6] climatechangetracker.org, Current Remaining Carbon Budget and Trajectory: Insights, Data, Charts. 2024. https://climatechangetracker.org/igcc/current-remaining-carbon-budget-and-trajectory-till-exhaustion.

by Hannah Back

In the first post of the series, I wrote about a common feeling of pessimism surrounding climate change, particularly in young people. I discussed some reasons why this occurring and put forth an alternative way of thinking that some scientists suggested. They said we should think about climate change in this way:

“Climate change is within our control and not inevitable, but changes must be comprehensive.”

If comprehensive changes must happen, what is our role in this? In this post, I’ll discuss how each of us contribute to climate change, and what we can do about it.

The driving force of climate change is carbon dioxide (CO2) emissions, which stay in the atmosphere for thousands of years and cause long lasting warming. Other greenhouse gases (GHGs) also contribute to warming. To see what we can do to limit climate change, we have to see how much we’re all contributing to CO2 emissions. In this post, I’ll mostly talk about CO2 and CO2-equivalent (CO2e) emissions. CO2e is just a convenient way scientists measure all greenhouse gases together.

We often hear about “making green choices” or discussion of person’s “carbon footprint”, but I always wondered how much of an impact a single person can really have.

So, let’s find out!

What (or who) is causing climate change?

A common statistic online says the following: Out of all the corporations in the world, about 100 are responsible for 71% of fossil fuel emissions¹.  These 100 companies are oil and gas industry related:

The top five companies contributing to global warming are all fossil fuel companies¹.

Is climate change fully in their hands, or is there anything we can do?

While these companies do hold responsibility for climate change because they sell fossil fuel products, they are still governed by supply and demand. They produce and sell these fossil fuels depending on how much their customers—gas stations, factories, power plants, and other transportation-related industries—will buy². If there were no purchasers, they would not make money.

An example of how this works can be seen from the Covid-19 pandemic. When Covid lockdowns hit in 2020, global industry came to a halt. There was a huge drop in demand for fossil fuels, and the price of oil fell³. Oil and gas companies lost billions of dollars in 2020.

In 2020, every oil company lost money⁴.

Emissions also fell because of the pandemic – people didn’t need to drive to work, businesses were closed, and industrial activity in general stopped. As a result, in 2020, the US (and other countries) emitted a lot less CO2e. In 2019, we emitted 18.5 tonnes (t) CO2e per person. In 2020 emissions went down to 16.7t—a drop of 1.8t⁴. That’s about a 600 million tonne CO2e drop across the entire US during 2020!

That’s 11% drop in American emissions compared to the previous year⁵.

Lessons Learned from the Pandemic

When demand for oil and gas drops, it’s because we are using less fossil fuels. And when we use less fossil fuels, less emissions are released.

The pandemic hurt oil and gas companies because it dropped the demand for oil and gas. But outside of a surprise force of nature like a pandemic, what can we to reduce our use of fossil fuels?

Can we reduce the amount of fossil fuels we use?

The EPA reports emissions by economic sector– transportation, electricity, industry, commercial/residential, and agriculture. This high-level reporting can make it hard to tell where these emissions are coming from.

Another way of looking at emissions accounting is by household use. Globally, household consumption is responsible for 72% of global GHG emissions⁷. American households are responsible for most US emissions, from things like personal transportation, heating/cooling/residential energy use, and food⁸. Luckily, these things are areas where we have some control.

More than 85% of US emissions are driven by household⁸.

Each US household generates 48-57 tons of CO2e per year. Multiply that by the number households, and you get 85%+ of US emissions.

The US also has a very high impact on climate change compared to other countries. We have a higher carbon footprint than other countries, even ones with a similar quality of life. In fact, American households were responsible for generating over 15% of global GHG emissions in 200¹⁰.

Americans generate more carbon dioxide than other countries with similar qualities of life⁹.

The good news is that as Americans, our lifestyle choices have a large impact on climate change. Relatively small changes we make can have a large impact.

In the next post, we’ll talk about what these changes could look like, and see how much of a difference it might make.

References

[1] T. Riley, Just 100 companies responsible for 71% of global emissions, study says, The Guardian (2017). https://www.theguardian.com/sustainable-business/2017/jul/10/100-fossil-fuel-companies-investors-responsible-71-global-emissions-cdp-study-climate-change.

[2] N. Burclaff, Research Guides: Oil and Gas Industry: A Research Guide: Downstream: Refining and Marketing, (n.d.). https://guides.loc.gov/oil-and-gas-industry/.

[3] H. S Blake;Muri,Steven M. ;Pallotta,Daniel J. ;Rogers,Marie;Weinhagen,Jonathan C. ;Wilson,Jeffrey, PPI and CPI seasonal adjustment during the COVID-19 pandemic : Monthly Labor Review: U.S. Bureau of Labor Statistics, Bureau of Labor Statistics (n.d.). https://www.bls.gov/opub/mlr/2022/article/ppi-and-cpi-seasonal-adjustment-during-the-covid-19-pandemic.htm.

[4] Petroleum in the United States, Wikipedia (2024). https://en.wikipedia.org/w/index.php?title=Petroleum_in_the_United_States&oldid=1219002459.

[5] US EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks, (2017). https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks.

[6] G. Dubois, B. Sovacool, C. Aall, M. Nilsson, C. Barbier, A. Herrmann, S. Bruyère, C. Andersson, B. Skold, F. Nadaud, F. Dorner, K.R. Moberg, J.P. Ceron, H. Fischer, D. Amelung, M. Baltruszewicz, J. Fischer, F. Benevise, V.R. Louis, R. Sauerborn, It starts at home? Climate policies targeting household consumption and behavioral decisions are key to low-carbon futures, Energy Research & Social Science 52 (2019) 144–158. https://doi.org/10.1016/j.erss.2019.02.001.

[7] R. Koide, M. Lettenmeier, L. Akenji, V. Toivio, A. Amellina, A. Khodke, A. Watabe, S. Kojima, Lifestyle carbon footprints and changes in lifestyles to limit global warming to 1.5 °C, and ways forward for related research, Sustain Sci 16 (2021) 2087–2099. https://doi.org/10.1007/s11625-021-01018-6.

[8] S.E. Eikenberry, A fair share: doing the math on individual consumption and global warming, 2018.

[9] These three charts show who is most to blame for climate change, MIT Technology Review (n.d.). https://www.technologyreview.com/2022/11/18/1063443/responsible-climate-change-charts/.

by Josie Mbaye

Find the lesson plans in the Earth Science and Astronomy area.