How do we know the CO2 levels hundreds of thousands of years ago?

The most direct evidence comes from tiny bubbles of ancient air trapped in the vast ice sheets of Antarctica. By drilling for ice cores and analyzing the air bubbles, scientists have found that, at no point during at least the past 800,000 years have atmospheric CO2 levels been as high as they are now.

How is the concentration of CO2 determined before records were kept?

One of the non-isotope proxies for CO2 dating back tens of millions of years is the stomatal index record. Stomata are microscopic “mouths” on plant leaves that open and close to let in CO2 but keep H2O from escaping. In a higher CO2 environment, plants grow more stomata per unit area.

How has the CO2 concentration in Earth’s atmosphere changed over the past thousand years?

The concentration of carbon dioxide in Earth’s atmosphere is currently at nearly 412 parts per million (ppm) and rising. This represents a 47 percent increase since the beginning of the Industrial Age, when the concentration was near 280 ppm, and an 11 percent increase since 2000, when it was near 370 ppm.

What is CO2 concentration?

CO2 Concentration CO2 is measured as parts per million (ppm), which is numerically equivalent to micromoles of CO2 per mole of air. The SI unit for CO2 concentration is µmol per mol. CO2 increases to more than 450 ppm because of cars and home heating.

How is CO2 measured in atmosphere?

Carbon Dioxide (CO2) is measured in parts-per-million (ppm) and reported in units of micromol mol-1 (10-6 mol CO2 per mol of dry air). Measurements are directly traceable to the WMO CO2 mole fraction scale.

How did CO2 form in Earth’s atmosphere?

Carbon dioxide (CO2) has been present in the atmosphere since the Earth condensed from a ball of hot gases following its formation from the explosion of a huge star about five billion years ago.

How the concentration of CO2 in the ocean changes with the depth of water?

At a depth of 1000 m, liquid CO2 is about 6\% less dense than seawater. Because liquid CO2 is more compress- ible than seawater, at a depth of 3000 m its density is similar to that of seawater. Thus liquid CO2 would be positively buoyant and rise if it were injected above 3000 m, but it would sink if injected deeper.