The video discusses the early discoveries of greenhouse gases and their impact on climate change, focusing on the work of scientists like Arrhenius, Tyndall, and Callendar. Arrhenius's calculations in the 19th century linked CO2 emissions to global warming, while Tyndall's experiments highlighted the role of gases in the atmosphere. Callendar's 20th-century research further connected rising CO2 levels to temperature increases, despite initial skepticism.

What was Arrhenius' conclusion about the role of greenhouse gases in Earth's climate?

• They are only produced by natural sources.

• They could cause a rise in world temperatures.

• They have no significant impact on climate.

• They are responsible for cooling the Earth.

How did John Tyndall contribute to the understanding of Earth's heat budget?

• He discovered that sunlight is the main factor.

• He proved that oxygen is the most absorptive gas.

• He found that water vapor and CO2 control the heat budget.

• He showed that nitrogen has no effect on heat absorption.

What did John Tyndall's experiments reveal about trace gases?

• They only affect the atmosphere during the day.

• They are less important than major gases like oxygen.

• They form a barrier that affects the atmosphere more than sunlight.

• They have no effect on Earth's atmosphere.

What was Guy Stewart Callendar's significant contribution to climate science?

• He proved that climate change is a natural cycle.

• He linked rising temperatures to increased CO2 levels.

• He showed that CO2 levels have no impact on climate.

• He discovered the greenhouse effect.

How was Callendar's work initially received by the scientific community?

• It was immediately accepted and praised.

• It was met with skepticism and criticism.

• It was ignored and forgotten.

• It was considered a breakthrough in physics.