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  1. Home
  2. Climate Solutions 101
  3. Unit 3: Reducing Sources

Unit 3: Reducing Sources

How can we stop harmful emissions in their tracks? Discover fascinating, up-to-date methods for halting emissions before they reach the atmosphere. This unit walks through the five largest sources of greenhouse gases—electricity, food, industry, transportation, and buildings—bringing the path to a safer, low-carbon economy into sharper relief. Learn which sources make up the biggest slices of the global emissions pie. 

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Expert Conversations

Ryan Allard, PhD
Ryan Allard, PhD

Former Fellow for Transportation and Buildings, Project Drawdown

Allard advances solutions to the climate challenge by sharing his broad knowledge of transportation systems and their impact on our climate. His specialties include: sustainable transport, passenger intermodality, intercity transport, competitive issues in transportation, and cooperation among transportation systems. Beyond these topics, Allard has published peer-reviewed research and presented at international conferences on transport solutions to reduce climate change, and on mass transit, high-speed rail, car-driver support technologies, and systems design that encourages socially optimum behavior. Prior to joining Project Drawdown, Allard earned degrees from the Massachusetts Institute of Technology as well as the University of Lisbon in Portugal. Follow him on Twitter and LinkedIn.

Hear more about transportation and emissions sources in Unit 3, which covers the biggest slices of the global emissions pie.

Follow Allard—transportation analyst—on a deep dive into exciting real-world climate solutions. From electric vehicles and trains to innovations in aviation, Allard reimagines a smarter, faster transportation system around the world.

28:29
Marcos Heil Costa, PhD
Marcos Heil Costa, PhD

Full Professor, Federal University of Viçosa

Costa has dedicated his career to geosciences, with a special emphasis on climatology. From the study of large-scale hydrology to micrometeorology, Costa is fascinated by the interactions between Earth’s air, land, and water. He earned his B.A. and M.S. from Brazil’s University Federal of Viçosa, and his doctorate in atmospheric and ocean sciences from the University of Wisconsin-Madison. Today, Costa is a full professor at his alma mater, the Federal University of Viçosa. Visit him online.

Hear more about the sources of greenhouse gas emissions in Unit 3, which brings the path to a safer, low-carbon economy into sharper relief. 

Explore Brazil’s role in implementing climate solutions with Costa, expert climatologist at the Federal University of Viçosa. Join Costa for a wide-ranging discussion focused on tropical deforestation, ethanol production, regenerative agriculture, and more.

25:31
Ryan Allard, PhD
Ryan Allard, PhD

Former Fellow for Transportation and Buildings, Project Drawdown

Allard advances solutions to the climate challenge by sharing his broad knowledge of transportation systems and their impact on our climate. His specialties include: sustainable transport, passenger intermodality, intercity transport, competitive issues in transportation, and cooperation among transportation systems. Beyond these topics, Allard has published peer-reviewed research and presented at international conferences on transport solutions to reduce climate change, and on mass transit, high-speed rail, car-driver support technologies, and systems design that encourages socially optimum behavior. Prior to joining Project Drawdown, Allard earned degrees from the Massachusetts Institute of Technology as well as the University of Lisbon in Portugal. Follow him on Twitter and LinkedIn.

Hear more about transportation and emissions sources in Unit 3, which covers the biggest slices of the global emissions pie.

Follow Allard—transportation analyst—on a deep dive into exciting real-world climate solutions. From electric vehicles and trains to innovations in aviation, Allard reimagines a smarter, faster transportation system around the world.

28:29
Marcos Heil Costa, PhD
Marcos Heil Costa, PhD

Full Professor, Federal University of Viçosa

Costa has dedicated his career to geosciences, with a special emphasis on climatology. From the study of large-scale hydrology to micrometeorology, Costa is fascinated by the interactions between Earth’s air, land, and water. He earned his B.A. and M.S. from Brazil’s University Federal of Viçosa, and his doctorate in atmospheric and ocean sciences from the University of Wisconsin-Madison. Today, Costa is a full professor at his alma mater, the Federal University of Viçosa. Visit him online.

Hear more about the sources of greenhouse gas emissions in Unit 3, which brings the path to a safer, low-carbon economy into sharper relief. 

Explore Brazil’s role in implementing climate solutions with Costa, expert climatologist at the Federal University of Viçosa. Join Costa for a wide-ranging discussion focused on tropical deforestation, ethanol production, regenerative agriculture, and more.

25:31

Key Graphics

Greenhouse Gas Sources
Sources of Greenhouse Gases from the Electricity Sector
Electricity Solutions
Sources of Greenhouse Gases from the Food, Agriculture, and Land Use Sector
Food, Agriculture, and Land Use Solutions
Sources of Greenhouse Gases from the Industry Sector
Industry Solutions
Sources of Greenhouse Gases from the Transportation Sector
Transportation Solutions
Sources of Greenhouse Gases from the Buildings Sector
Buildings Solutions
Other Sources of Greenhouse Gases
Sources of Greenhouse Gases Segmented by Sector
Download All

Learn More

The Drawdown Review

Project Drawdown's 2020 publication is the first major update to the research and analysis of climate solutions since Drawdown, its 2017 best-selling book. See pages 14 – 49 for a deeper dive on reducing the largest sources of emissions across sectors.

Drawdown Solutions: Electricity Overview

Today, electricity production gives rise to 25% of heat-trapping emissions globally. How do the means of generating, transmitting, storing, and using electricity need to evolve?

Drawdown Solutions: Food, Agriculture, & Land Use Overview

Solutions in this sector—which generates 24% of greenhouse gas emissions worldwide—are focused on waste and diets, ecosystem protection, and better agriculture practices.

Drawdown Solutions: Industry Overview

Industry’s hard work certainly propels economic activity but it also creates 21% of all heat-trapping emissions—and some of the hardest to halt. Industry solutions cluster around materials, waste, refrigerants, and energy efficiency.

Drawdown Solutions: Transportation Overview

Transportation is responsible for 14% of global greenhouse gas emissions—read more from Project Drawdown about exciting solutions that address alternatives, fuel efficiency, and electrification.

Drawdown Solutions: Buildings Overview

It’s no surprise that buildings are major drivers of emissions, producing 6% of heat-trapping emissions worldwide. Discover solutions oriented around energy efficiency, energy sources, and refrigerants.

Drawdown Primer: Farming Our Way Out of the Climate Crisis

Hot off the digital press: it’s Project Drawdown’s recent publication focused on changing our modern land use, agriculture practices, and food systems.

How Do We Farm Our Way Out of the Climate Crisis

Looking for more beyond the free Primer above? Read Foley’s Medium piece on Project Drawdown’s exploration of climate solutions across global land use and agriculture.

Beef Rules

Does beef have any place in a healthy climate future? Discover a few basic rules around responsible consumer choices in another piece from Foley’s Medium site.

Next Unit

Unit 4: Supporting Sinks and Improving Society

Climate Solutions 101
Unit 1: Setting the Stage
Unit 2: Stopping Climate Change
Unit 3: Reducing Sources
Unit 4: Supporting Sinks and Improving Society
Unit 5: Putting It All Together
Unit 6: Making It Happen

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