Question

The partial pressure of carbon dioxide varies with seasons. Would you expect the partial pressure in the Northern Hemisphere to be higher in the summer or winter? Explain.

Short answer

The partial pressure of carbon dioxide in the Northern Hemisphere would be expected to be higher in winter since there's less photosynthetic activity to absorb CO2, while the emission of CO2 by burning of fossil fuels continues steadily throughout the year.

Step-by-step solution

Understanding the concept of partial pressure

Partial pressure is the pressure that an individual gas would be exerting if it were alone occupying the whole volume. Since the question involves analysis of carbon dioxide's partial pressure, it's important to understand that the partial pressure of a gas is directly proportional to its concentration.

Understanding the influence of climate changes and seasonal variations

In the Northern Hemisphere, the primary source of carbon dioxide is the burning of fossil fuels, whilst plants absorb CO2 from the atmosphere during photosynthesis which occurs prevalently in the summer months.

Determining the variation of CO2 with seasons

Since photosynthesis rates drop in winter due to less sunlight and most organisms remain inactive or die, leading to less absorption of CO2. On the other hand, burning of fossil fuels remains relatively consistent, this means that more CO2 remains in the atmosphere, hence, the partial pressure of CO2 becomes higher in winter.