Palaeoclimatic data refers to the information that provides evidence about Earth’s past climates before the advent of modern instrumental records. Since systematic meteorological measurements extend back only about one and a half centuries, scientists rely on natural and indirect archives to reconstruct long-term climate variations. These sources are crucial for understanding the mechanisms of climate change, distinguishing natural variability from anthropogenic influences, and predicting future climatic trends. Palaeoclimatic data are derived from a variety of natural archives and proxy indicators that preserve information about atmospheric conditions, temperature, precipitation, ice cover, and ocean circulation. Each source has its own strengths, limitations, and temporal or spatial coverage, and collectively they provide a comprehensive picture of Earth’s climatic history. One of the most important sources of palaeoclimatic data is ice cores. Extracted from ice sheets in Greenland, Antarctica, and mountain glaciers, these cores contain layers of compacted snow and ice that accumulate year after year. The trapped air bubbles within the ice serve as time capsules, preserving samples of the ancient atmosphere. By analyzing the concentrations of greenhouse gases such as carbon dioxide, methane, and nitrous oxide, scientists can reconstruct past atmospheric composition. Additionally, isotopic ratios of oxygen and hydrogen in the ice layers provide information about past temperatures. Ice cores can extend back hundreds of thousands of years, with the longest records reaching nearly 800,000 years, thus offering invaluable insights into glacial-interglacial cycles and abrupt climate changes. Tree rings, or dendroclimatology, provide another well-established source of palaeoclimatic data. Trees in temperate and subarctic regions often produce annual growth rings whose thickness varies according to environmental conditions such as temperature and precipitation. By carefully measuring the width, density, and isotopic composition of tree rings, scientists can infer past climate variability on annual to decadal scales. Cross-dating among different trees in a region allows for the extension of chronologies back thousands of years. Tree ring records are particularly valuable for studying droughts, seasonal temperature fluctuations, and regional climate variability, although they are limited to terrestrial environments where long-lived trees are present. Marine and lake sediments are equally significant archives of past climate. As sediments accumulate over time on ocean floors and in lake basins, they trap microfossils, pollen, minerals, and organic matter that reflect the prevailing environmental conditions. In marine sediments, the shells of microscopic organisms such as foraminifera and diatoms preserve oxygen isotope ratios that serve as indicators of past ocean temperatures and ice volume. The chemical composition of these sediments also reveals changes in ocean circulation, nutrient availability, and biological productivity. Similarly, lake sediments can preserve pollen grains, charcoal fragments, and varves—annual sediment layers—that provide insights into regional vegetation, fire history, and hydrological changes. These records can extend back millions of years