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Energy and Climate Change

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Fast Facts About
Climate Change

The greenhouse effect is the process through which heat is trapped near the Earth's surface by gases known as greenhouse gases (GHGs). GHGs absorb infrared radiation from the Sun and Earth in the form of heat, warming the Earth’s surface. GHGs occur naturally in our atmosphere and are important for regulating the Earth’s temperature. Important greenhouse gases are carbon dioxide, methane, nitrous oxide, and hydrofluorocarbons. 

Rising GHG levels due to carbon-intensive human activities since pre-industrial times have resulted in an increase in the Earth’s surface temperature, which is known as global warming. Global warming is causing climate change and resulting in harmful impacts on humans and our environment.

Carbon dioxide (CO2) has had the greatest impact on climate change – its atmospheric levels have increased by 40% since the pre-industrial peak. Methane is also a powerful greenhouse gas because it has 80 times the warming power of CO2 over the first 20 years after it reaches the atmosphere. (Visit our Natural Gas page for more information on methane.)

Climate change is an urgent problem. We have the tools and solutions to tackle climate change, but implementation remains a huge challenge due to lack of social will, the high cost of scaling solutions, lack of robust government policy, and the vested interests of fossil fuel companies and fossil fuel exporting countries.

Tracking Climate Change

Average Global Surface Temperature Increase

1.1°C  / 2.0°F (2011-2020)
1.35 °C / 2.43 °F (2023)
above pre-industrial levels (1850-1900)

2023 was the warmest year since global records began in 1850, and the 10 warmest years in the historical record have all occurred in the past decade (2014-2023).

January 2024 was the warmest January on record.

Scientists agree that warming above 2°C will cause severe and catastrophic effects to Earth’s ability to sustain human life and that of other species.

Read this MIT Climate article for more information.

Watch this 30-second NASA animation of global temperature anomalies from 1880 to 2021.

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“It is unequivocal that human influence has warmed the atmosphere, ocean and land.” - Intergovernmental Panel on Climate Change (IPCC), 2023

Global Sources and Sinks of GHG Emissions

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Key Impacts of Climate Change

There are numerous negative environmental impacts of climate change, many of which affect human health and morbidity. These include an increase in the number and duration of droughts, heatwaves, winter storms, and wildfires, as well as sea level rise, more frequent and more intense hurricanes, and biodiversity loss.

Global Mean Sea Level Rise

6 - 10 in / 15 - 25 cm
over the past 100 years

4.2 in / 10.7 cm
over the past 20 years

And the rate of global mean sea level rise is increasing:

  • 1.32mm/year (1901-1971)
  • 1.87mm/year (1971-2006)
  • 3.69mm/year (2006-2018)

Even these seemingly modest levels of increase can make coastal areas uninhabitable for humans and have been shown to cause greater flooding and worsen the impact of hurricanes.

Ocean Acidification

Today’s surface ocean waters are 30% more acidic than pre-industrial ocean waters.

Ocean acidification is a result of CO2 dissolving in the ocean and forming carbonic acid.

The increased acidity can dissolve the calcium carbonate shells or skeletons of marine life like corals, clams, and mussels, which are often at the bottom of the food chain. This means that ocean acidification can impact many marine species.

More Frequent and More Severe Wildfires

In California, land area burned due to wildfires increased by 320% between 1996 and 2021.

In Canada, the average area burned during a wildfire has doubled since 1970. The total area burned in the 2023 Canadian wildfire season, 45.5 million acres, was 6 times the 10 year average.

In Australia, an estimated 480 million animals died, including 15% of the koala population, in the 2019/2020 bushfires.

Additional wildfire impacts:

  • Air pollution - wildfire smoke contains harmful pollutants that cause cardiovascular and respiratory illness, asthma attacks, and premature death in humans
  • GHG emissions - wildfires release large quantities of carbon dioxide while burning, continue to release carbon dioxide as burned forests decompose, and reduce the land sink by destroying forests
  • Economic - the annual cost of wildfires in the US ranges from $394 billion to $893 billion, including costs from property damage, direct and indirect deaths and injuries, health impacts from wildfire smoke, income loss, and other factors

Increased Risks of Extinction

According to the IPCC, “about one-third of all plant and animal species are at high risk of extinction by 2070 if climate change continues at its current rate.”

Climate change increases the likelihood of extinction for at least 10,967 threatened species.

Climate Refugees from Natural Disasters

31.8 million
internal climate refugees* in 2022

of all refugees are climate refugees

Natural disaster related displacements in 2022 were 41% higher than the annual average over the past 10 years.

Heat Related Deaths

of heat related deaths are due to climate change

Heat wave frequency in the US has increased from 2 per year in the 1960s to 6 per year in the 2010s and 2020s.

60,000 people died in Europe in 2022 due to extreme heat.

Flooding and Habitable Land Loss

of the global population lives in low-lying coastal areas (<10 m above sea level), which are most susceptible to the impacts of a rising sea level

*Internal climate refugees are displaced within their country

Countries Particularly Vulnerable to Climate Change Impacts

Impacts of climate change are not equitably distributed. The countries that are or will be hardest hit by climate change are the ones that have contributed the least to it and have fewer resources to combat it.

Food Scarcity

Sub-saharan Africa, South Asia, Southeast Asia

Food scarcity can be caused by increased drought, water scarcity, and natural disasters.

Rising temperatures can also make growing crops more expensive, driving more people into poverty and food insecurity.


% of land area burned (2012-2022 average)

Sierra Leone 31% 🇸🇱
Angola 29% 🇦🇴
Zambia 29% 🇿🇲
Guinea 28% 🇬🇳
Central African Republic 28% 🇨🇫
Mozambique 24% 🇲🇿
Ghana 20% 🇬🇭

Geographies With Emerging Wildfire Risk

Siberia and the Arctic*, the Amazon (and other rainforests)

Sea Level Rise

Small island nations like Tuvalu, the Maldives, and the Marshall Islands are most at risk of impacts from sea level rise, including becoming uninhabitable.

These nations also have some of the smallest contributions to GHG emissions.

Heat Waves

Afghanistan, Central American nations like Guatemala, Honduras, Nicaragua

Their vulnerability includes not only their risk of heat waves, but also their inability to prepare and respond to them.

*Fires in these regions can melt permafrost, releasing significant amounts of trapped CO2 and methane into the atmosphere

Global Warming Potentials (GWP)

GWP is a measure of how much heat a GHG can trap in the atmosphere over specific time intervals, typically 20 and 100 years. GWP takes into account both the heat trapping ability of GHGs and their lifetime, which is the length of time they stay in the atmosphere.

 Lifetime (years)20 year GWP100 year GWP
Carbon Dioxide, CO2100-1,00011
Methane, CH4128127
Nitrous Oxide, N2O109273273
Hydrofluorocarbon, HFC-134a144,1441,526

Human GHG Emissions

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GHG Emissions by Country

GHG emissions measurements by country can vary based on where/to whom emissions are assigned. For example, if a good is produced in China for a customer in the US, the emissions could be assigned to either country. Production-based measurements assign emissions to the producing country. Consumption-based emissions measurements are adjusted for trade and more accurately reflect the consumption and lifestyle choices of a country’s citizens. Most emissions data, including the data below, is presented as production-based. Consumption-based data is more difficult to calculate accurately.

Highest Annual GHG Emissions

China 26% 🇨🇳
US 11% 🇺🇸
India 7% 🇮🇳
of global annual GHG emissions

Per Capita GHG Emissions for the Top Three GHG Emitters (tCO2e*/person)

US 16.0 🇺🇸
China 8.7 🇨🇳
India 2.3 🇮🇳

Highest Cumulative GHG Emissions

US 24% 🇺🇸
EU 17% 🇪🇺
China 15% 🇨🇳
of cumulative GHG emissions

*tons of CO2 equivalent

US GHG Emissions

Highest Annual GHG Emissions

Texas 14%
California 6%
of annual US GHG emissions

Highest Cumulative GHG Emissions

Texas 12%
California 6%
Pennsylvania 4%
Ohio 4%
of cumulative US GHG emissions

Factors Contributing to Lack of Social Will to Act on Climate Change in the US

Lack of Belief

Only 58% of US adults believe in human-caused climate change

Misinformation Campaigns From the Oil and Gas Industries

Millions of dollars have been spent on ads attacking renewable energy sources and promoting natural gas

As of 2022, more than 2 dozen US cities, counties, and states are suing oil and gas companies over their role in the increasing hazards of climate change.

Climate Change Can Be Difficult to Understand and Communicate

Only 46% of US adults believe global warming will harm them personally

Climate change has short term costs, but long term impacts.

How Do We Solve Climate Change?

Top 6 Cost-Effective Solutions to Climate Change by Mitigation Potential

Solar photovoltaics
Wind energy
Energy efficiency and electrification in buildings
Decarbonized industrial processes
Vehicle electrification

How Companies and Organizations Categorize GHG Emissions

Scope 1, 2, and 3 emissions categories provide standardized ways for companies and organizations to account for and report their greenhouse gas emissions. The categories are based on the level of control that entities have over their emissions.

Scope 1

Direct emissions from sources controlled or owned by an organization

Includes emissions from:

  • Company vehicles
  • Fuel combustion
  • Fugitive emissions (from facility appliances or processes)

Scope 2

Indirect emissions associated with the purchase of electricity, steam, heat, or cooling; emissions do not physically occur at facilities owned or controlled by the reporting organization

Includes emissions from:

  • Electricity
  • Heat
  • Steam

Scope 3

Indirect emissions that an organization causes in its value chain (upstream and downstream of the organization’s activities); includes all emission sources not included in Scope 1 and 2

Includes emissions from:

  • Purchased goods and services
  • Business travel
  • Waste disposal
  • Transportation and distribution
  • Consumer's use of sold products

Solution Drivers

  • Cost-competitive solutions are ready to scale today
  • Policy support at international, national, and local levels (e.g., GHG reduction targets, clean electricity targets, carbon pricing mechanisms, building and vehicle electrification mandates)
  • Private sector engagement from large corporates, investors
  • Continued innovation and cost declines in hard-to-abate sectors (industry, air and ocean travel) and for engineered carbon capture technology

Solution Barriers

  • Need more ambitious policy from governments at all levels to accelerate scaling of solutions, including effective carbon pricing
  • Need more investment capital to accelerate scaling of solutions
  • Lack of social will: 
    • Divergence between public opinion and the science (e.g, only 58% of US adults believe in human-caused climate change)
    • Influence of incumbent fossil fuel interests
    • Competing priorities (energy prices and geopolitics)
    • Lack of international climate agreement
    • Lack of individual empowerment

Updated March 2024

Our 10-Minute Take On
Climate Change

If you're short on time, start by watching this video of key highlights from our lecture on Energy and Climate Change.

Kirsten Stasio

Presented by: Kirsten Stasio, Adjunct Lecturer, Civil and Environmental Engineering, Stanford University; CEO, Nevada Clean Energy Fund (NCEF)
Recorded: Nov 15, 2022  Duration: 12 minutes

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Before You Watch Our Lecture on
Energy and Climate Change

We assign videos and readings to our Stanford students as pre-work for each lecture to help contextualize the lecture content. We strongly encourage you to review the readings and videos below before watching our lecture on Energy and Climate Change

Our Lecture on
Energy and Climate Change

This is our Stanford University Understand Energy course lecture on climate change. We strongly encourage you to watch the full lecture to understand the significant role that energy plays in climate change and to be able to put this complex topic into context. For a complete learning experience, we also encourage you to watch / read the videos and readings we assign to our students before watching the lecture.

Kirsten Stasio

Presented by: Kirsten Stasio, Adjunct Lecturer, Civil and Environmental Engineering, Stanford University; CEO, Nevada Clean Energy Fund (NCEF)
Recorded on: September 29, 2023   Duration: 55 minutes

Table of Contents

(Clicking on a timestamp will take you to YouTube.)
00:00 Introduction 
04:20 What is the Science Behind Climate Change? 
21:08 How Do We Garner the Social Will to Act on Climate Change? 
34:12 How Do We Solve Climate Change?

Lecture slides available upon request.

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Additional Resources About
Climate Change

Stanford University Professors

Fast Facts Sources

More details available on request.
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