Ilmastokäyrä

Ilmastokäyrä, often translated as "climate curve" or "climate spiral," is a visual representation of Earth's climate history, specifically focusing on temperature fluctuations over geological timescales. The most famous example is the "hockey stick graph," which depicted a relatively stable climate for centuries followed by a sharp increase in global temperatures in the 20th century, resembling the shape of a hockey stick.

These graphical representations are constructed using proxy data, which are indirect measures of past climate conditions. Examples of proxy data include ice cores, tree rings, sediment layers, and coral reefs. Scientists analyze these proxies to reconstruct past temperatures, atmospheric composition, and other climate variables. The resolution of these reconstructions varies depending on the proxy and the time period being studied.

The concept of the ilmastokäyrä has been instrumental in communicating scientific findings about climate change to the public and policymakers. It highlights long-term trends and allows for the comparison of current conditions with those of the distant past. While the specific shapes and details of different ilmastokäyrät can vary based on the data sources and methodologies used, the general scientific consensus supports the interpretation that recent warming is unprecedented in recent geological history. Ongoing research continues to refine these reconstructions and improve our understanding of past and future climate.