4.1 The evidence for climate change

• • Evidence from fossil records show that global temperatures have fluctuated over the last 5 million years

  • Analysis of ocean sediment and Antarctic snow shows fluctuations between glacial (colder) and inter-glacial (warmer) periods.

  • Recorded Temperature Changes: Increase in recorded global temperatures, especially after the mid-1970s.

Melting Ice and Glaciers:

• • Decrease in the extent of Arctic sea ice.

  • Glaciers are disappearing

Rising Sea Levels:

• • Melting glaciers contribute to freshwater increase.

  • Thermal expansion causing sea levels to rise.

  • Low-lying areas facing flood risks.

Seasonal Shifts:

• • Changes in tree flowering and bird migration patterns.

  • Earlier bird nesting observed compared to the 1970s.

Misconception 1: Weather just happens without any real pattern or reason.

Reality: There's a system called global atmospheric circulation that helps us predict weather because it shapes where and how air moves around Earth.

Misconception 2: Climate change is a recent phenomenon.

Reality: Climate has been changing over millions of years, but recent human activities have significantly accelerated this process.