The need for high-resolution paleoclimate research

Comparing recent warming against past temperature changes is crucial for understanding the importance of greenhouse gas emissions for the global climate system. Although tree ring-based temperature and hydroclimate reconstructions form the backbone of high-resolution paleoclimatology, the data used, methods applied, and concepts proposed are far from perfect. Here, we open dialogue on challenges of dendroclimatology and scientific collaboration. We emphasise that temperature signals in tree-ring chronologies are restricted to extra-tropical growing seasons, and that far too little such data exist for the Southern Hemisphere and the Common Era. We notice that the preservation of both, high- and low-frequency information is prone to uncertainties, that investigations of growth-climate relations are hindered by short and spatially inconsistent meteorological measurements, and that geopolitical tension increasingly constrains data accessibility. Finally, we highlight the need for paleoclimate research and funding, with a focus on annually resolved and absolutely dated timeseries for the Holocene.