WHO WE ARE
Are humans causing or contributing to global warming?
Yes, by increasing the abundance of greenhouse gases in the atmosphere, human activities are amplifying Earth’s natural greenhouse effect. Virtually all climate scientists agree that this increase in heat-trapping gases is the main reason for the 1.8°F (1.0°C) rise in global average temperature since the late nineteenth century. Carbon dioxide, methane, nitrous oxide, ozone, and various chlorofluorocarbons are all human-emitted heat-trapping gases. Among these, carbon dioxide is of greatest concern to scientists because it exerts a larger overall warming influence than the other gases combined.
At present, humans are putting an estimated 9.5 billion metric tons of carbon into the atmosphere each year by burning fossil fuels, and another 1.5 billion through deforestation and other land cover changes. Of this human-produced carbon, forests and other vegetation absorb around 3.2 billion metric tons per year, while the ocean absorbs about 2.5 billion metric tons per year. A net 5 billion metric tons of human-produced carbon remain in the atmosphere each year, raising the global average carbon dioxide concentrations by about 2.3 parts per million per year. Since 1750, humans have increased the abundance of carbon dioxide in the atmosphere by nearly 50 percent
WHAT WE DO
We know that climate change is happening – but there are plenty of things individuals can do to help mitigate it. Here’s your the most effective strategies.
How harmful are my flying habits?
Planes run on fossil fuels, and we haven’t figured out a scaleable alternative. Although some early efforts to use solar panels to fly around the world have had success, we are still decades away from commercial flights running on solar energy.
A normal transatlantic round-trip flight can release around 1.6 tonnes of CO2, according to Nicholas’s study – almost as much as the average yearly emissions of one person in India. This also highlights the inequality of climate change: while everyone will be affected, only a minority of humans fly and even fewer people take planes often.
There are groups of scientists and members of the public who have decided to give up flying or who fly less. Virtual meetings, holidaying in local destinations or using trains instead of planes all are ways to cut down.
Wondering how much your travel contributes to climate change? Measure your carbon emissions in this calculator by researchers at the University of California, Berkeley.
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Other than that, what’s the best daily action I can take?.
One 2017 study co-authored by Lund University’s Nicholas ranked 148 individual actions on climate change according to their impact. Going car-free was the number-one most effective action an individual could take (except not having kids – but more on that on that later). Cars are more polluting compared to other means of transportation like walking, biking or using public transport.
In industrialised countries such as European nations, getting rid of your car can reduce 2.5 tonnes of CO2 – about one-fourth of the average yearly emissions (9.2 tonnes) contributed by each person in developed countries of the Organisation for Economic Co-operation and Development (OECD).
“We should choose more efficient vehicles and, whenever possible, switch directly to electric vehicles,” says Maria Virginia Vilarino, co-author of the mitigation chapter in the IPCC’s latest report.
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