It has also suggested that the climate might warm by as much as 10 degrees Fahrenheit over the next years. The sea levels are constantly rising as fresh water marshlands, low-lying cities, and islands have been inundated with seawater.
There have been changes in rainfall patterns, leading to droughts and fires in some areas, and flooding in other areas. The more greenhouse gases concentrate in the atmosphere, the more heat gets locked up in the molecules. Scientists have known about the greenhouse effect since , when Joseph Fourier calculated that the Earth would be much colder if it had no atmosphere. This natural greenhouse effect is what keeps the Earth's climate livable. Without it, the Earth's surface would be an average of about 60 degrees Fahrenheit 33 degrees Celsius cooler.
In , the Swedish chemist Svante Arrhenius discovered that humans could enhance the greenhouse effect by making carbon dioxide , a greenhouse gas. He kicked off years of climate research that has given us a sophisticated understanding of global warming. Levels of greenhouse gases have gone up and down over the Earth's history, but they had been fairly constant for the past few thousand years.
Global average temperatures had also stayed fairly constant over that time— until the past years. Through the burning of fossil fuels and other activities that have emitted large amounts of greenhouse gases, particularly over the past few decades, humans are now enhancing the greenhouse effect and warming Earth significantly, and in ways that promise many effects , scientists warn.
Human activity isn't the only factor that affects Earth's climate. Volcanic eruptions and variations in solar radiation from sunspots, solar wind, and the Earth's position relative to the sun also play a role. Changes in solar radiation levels as well as minute particles suspended in the atmosphere from volcanic eruptions , for example, have contributed only about two percent to the recent warming effect.
The balance comes from greenhouse gases and other human-caused factors, such as land use change. The short timescale of this recent warming is singular as well.
Volcanic eruptions , for example, emit particles that temporarily cool the Earth's surface. But their effect lasts just a few years. On the other hand, the types of global temperature fluctuations that have contributed to ice ages occur on a cycle of hundreds of thousands of years.
For thousands of years now, emissions of greenhouse gases to the atmosphere have been balanced out by greenhouse gases that are naturally absorbed. As a result, greenhouse gas concentrations and temperatures have been fairly stable, which has allowed human civilization to flourish within a consistent climate.
Now, humans have increased the amount of carbon dioxide in the atmosphere by more than a third since the Industrial Revolution. Changes that have historically taken thousands of years are now happening over the course of decades. Also, a new and more unpredictable climate poses unique challenges to all life. Historically, Earth's climate has regularly shifted between temperatures like those we see today and temperatures cold enough to cover much of North America and Europe with ice.
The difference between average global temperatures today and during those ice ages is only about 9 degrees Fahrenheit 5 degrees Celsius , and the swings have tended to happen slowly, over hundreds of thousands of years. But with concentrations of greenhouse gases rising, Earth's remaining ice sheets such as Greenland and Antarctica are starting to melt too.
That extra water could raise sea levels significantly, and quickly. The rate of loss could speed up if we keep burning fossil fuels at our current pace, some experts say, causing sea levels to rise several meters in the next 50 to years and wreaking havoc on coastal communities worldwide.
A: Each year scientists learn more about the consequences of global warming , and each year we also gain new evidence of its devastating impact on people and the planet. As the heat waves, droughts, and floods associated with climate change become more frequent and more intense, communities suffer and death tolls rise. Global warming is already taking a toll on the United States. Though everyone is affected by climate change, not everyone is affected equally. Indigenous people, people of color, and the economically marginalized are typically hit the hardest.
Inequities built into our housing , health care , and labor systems make these communities more vulnerable to the worst impacts of climate change—even though these same communities have done the least to contribute to it. A: In recent years, China has taken the lead in global-warming pollution , producing about 26 percent of all CO2 emissions. The United States comes in second. And America is still number one, by far, in cumulative emissions over the past years.
As a top contributor to global warming, the United States has an obligation to help propel the world to a cleaner, safer, and more equitable future. Our responsibility matters to other countries, and it should matter to us, too.
But in order to avoid the worsening effects of climate change, we need to do a lot more—together with other countries—to reduce our dependence on fossil fuels and transition to clean energy sources. Despite the lack of cooperation from the Trump administration, local and state governments made great strides during this period through efforts like the American Cities Climate Challenge and ongoing collaborations like the Regional Greenhouse Gas Initiative. Meanwhile, industry and business leaders have been working with the public sector, creating and adopting new clean-energy technologies and increasing energy efficiency in buildings, appliances, and industrial processes.
Today the American automotive industry is finding new ways to produce cars and trucks that are more fuel efficient and is committing itself to putting more and more zero-emission electric vehicles on the road.
Developers, cities, and community advocates are coming together to make sure that new affordable housing is built with efficiency in mind , reducing energy consumption and lowering electric and heating bills for residents.
And renewable energy continues to surge as the costs associated with its production and distribution keep falling.
In renewable energy sources such as wind and solar provided more electricity than coal for the very first time in U. President Biden has made action on global warming a high priority. On his first day in office, he recommitted the United States to the Paris Climate Agreement, sending the world community a strong signal that we were determined to join other nations in cutting our carbon pollution to support the shared goal of preventing the average global temperature from rising more than 1.
Scientists say we must stay below a 2-degree increase to avoid catastrophic climate impacts. And significantly, the president has assembled a climate team of experts and advocates who have been tasked with pursuing action both abroad and at home while furthering the cause of environmental justice and investing in nature-based solutions.
A: No! Wondering how you can be a part of the fight against global warming?
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