Résumé
The Early–Middle Pleistocene Transition (EMPT, ~1.4–0.4 Ma) marks a major shift in the Earth's climate system, with glacial–interglacial cycles evolving from ~40,000-year obliquity-paced intervals to longer, asymmetric ~100,000-year cycles. This transition occurred without major changes in orbital forcing, implying that internal climate mechanisms played a key role. However, these mechanisms remain poorly understood, especially in the understudied Eastern Mediterranean region. Here we reconstruct environmental and climate changes across the EMPT from the Acıgöl Basin in southwestern Türkiye (1.3–0.5 Ma). Vegetation dynamics, lake-level changes, and climate variability were investigated using a multi-proxy (pollen, NPPs) and multi-method approach combining the Modern Analogue Technique (MAT), Weighted Averaging Partial Least Squares regression (WA-PLS), Random Forest (RF), Boosted Regression Trees (BRT), and Climatic Amplitude Method (CAM).The pollen record reveals a persistent dominance of steppe vegetation, alternating between Amaranthaceae–Artemisia assemblages and grass-rich steppes with limited forest expansion during more humid phases. Relict taxa are rare and decline markedly during the EMPT, indicating that Southwestern Anatolia was less favourable for moisture-demanding species than other Mediterranean regions. Alternating abundances of Botryococcus and Chrysophyceae suggest fluctuations in lake level and trophic status under predominantly oligotrophic conditions. Pollen-based climate reconstructions indicate a general aridification trend, especially between 1.1 and 0.8 Ma, with more humid interglacials and drier glacials. These patterns align with other Eastern Mediterranean records and reflect both high-latitude ice-sheet dynamics and low-latitude forcing. Wavelet analysis reveals a dominant 41-ka obliquity cyclicity around 1.1 Ma.