<p>Since forests harbor much of the Earth’s biodiversity, the variation in forest diversity with climate change has received increasing worldwide attention in recent decades. Although extensive studies have been conducted on this, reaching a general conclusion is difficult. This may be attributed to the inconsistencies in diversity indices, sampling scales, recording approaches, environmental conditions, and vegetation types across the study sites. We used identical method to evaluate the responses of global forest biodiversity to climate change. Twenty-five forest protected areas were selected, each containing a thousand plots of 8100 m². Spectral diversity indices were extracted from Landsat satellite images to predict the likely responses of forest species diversity to 42 climatic scenarios using 12 parametric and non-parametric statistical models. Operating with various climate changes, mostly increased temperature and less precipitation, most projected climatic scenarios demonstrated a general trend of increase in spectral alpha diversity regardless of forest type. Moreover, considerable biotic homogenization was predicted for the next few decades, with an intensive increase from low to high latitudes. Detecting plant diversity change under climate warming for various global ecosystems from remotely sensed data is a large advancement in applied ecology. The results of the present study suggest that forest protected areas can intimately change due to climate change. Therefore, urgent strategies need to be developed to ensure the survival of endemic species under predicted climatic scenarios. The species may potentially require human assistance to adjust to their distribution ranges.</p>