greenhouse gas emissions have been increasing for the last 50 years

greenhouse gas emissions have been causing climate change

greenhouse gas emissions have been decreasing for the last 50 years

greenhouse gas emissions have been staying the same for the last 50 years

Earth's climate is gradually warming.

Global warming is caused by humans.

Tectonic activity is causing movement of ice.

Global warming only affects the ice caps, not the rest of the planet.

The graph shows how the length of the growing season in the United States has INCREASED over the past century compared with the long-term average.

The graph shows how the length of the growing season in the United States has DECREASED over the past century compared with the long-term average.

The graph shows how the length of the growing season in the United States has STAYED THE SAME over the past century compared with the long-term average.

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all of these

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Ice coverage in the arctic varies depending on the time of year.

Ice coverage in the arctic has been steadily declining since the 1970s.

The absolute maximum of ice coverage occurred in the 1980s and the absolute minimum of ice coverage occurred in 2020.

First leaf date is occurring earlier in the year in most of the United States, but later in the year in the south eastern United States.

The first day of spring comes sooner in the southern United States and later in the rest of the United States.

First leaf date is occurring earlier every year due to climate change.

The first day of spring comes later in the southern United States and earlier in the rest of the United States.

It is unlikely that the Sun has caused the observed global temperature warming trend over the past half-century.

It is probable that the Sun has caused the observed global temperature warming trend over the past half-century.

It is unlikely that humans caused the observed global temperature warming trend over the past half-century.

It is probable that humans caused the observed global temperature warming trend over the past half-century.

to show that global temperatures are rising at an unprecedented rate

to illustrate how industrial activities impact global temperature

The long term average of the growing season is 0 days.

The length of growing season in 2020 is longer than in 1950.

The length of the growing season in 1980 was close to average.

This data did not include all 50 states because Alaska and Hawaii were geographic outliers.

carbon dioxide

methane

chlorofluorocarbons

nitrous oxide

northern United States

south eastern United States

central United States

the West Coast