The Brazilian Amazon provides important hydrological cycle functions, including precipitation regimes that bring water tothe people and environment and are critical to moisture recycling and transport, and represents an important variable forclimate models to simulate accurately. This paper evaluates the performance of 13 Coupled Model Intercomparison Projectphase 6 (CMIP6) models. This is done by discussing results from spatial pattern mapping, Taylor diagram analysis and Taylorskill score, annual climatology comparison, and Empirical Orthogonal Function (EOF) analysis. Precipitation analysis shows1) This region displays a more uniform spatial distribution of precipitation with higher rainfall in the north-northwest anddrier conditions in the south. Models tend to underestimate northern values or overestimate the central to northwest averages.2) Southern Amazon has a more defined dry season (June, July, and August) and wet season (December, January, andFebruary) and models are able to simulate this well. Northern Amazon dry season tends to occur in August, September, andOctober and the wet season occurs in March, April, and May, and models are not able to capture the climatology as well.Models tend to produce too much rainfall at the start of the wet season and tend to either over- or under-estimate the dryseason, although ensemble means typically display the overall pattern more precisely. 3) EOF analysis of models are able tocapture the dominant mode of variability, which was the annual cycle or SAMS. 4) When all evaluation metrics are taken intoaccount the models that perform best are CESM2, MIROC6, MRIESM20, SAM0UNICON, and the ensemble mean. Thispaper supports research in determining the most up to date CMIP6 model performance of precipitation regime for 1981-2014for the Brazilian Amazon. Results will aid in understanding future projections of precipitation for the selected subset ofglobal climate models and allow scientists to construct reliable model ensembles, as precipitation plays a role in many sectorsof the economy, including the ecosystem, agriculture, energy, and water security.

Southern California has seen a resurgence of winegrowing regions in the past few decades, however the future of winegrape climatic suitability in the area has not been exhaustively explored. This study evaluated the future climate suitability for the cultivation of winegrape and potential global warming impacts on southern California’s winegrowing regions through a series of high-resolution surface air temperature and precipitation projections obtained with the WRF-SSIB regional climate model. Results reveal that by mid-21st-century the surface air temperature will increase by approximately 1.2 °C, while average precipitation will decrease by as much as 11% in the southern winegrowing areas under the Intergovernmental Panel on Climate Change high greenhouse-gas emissions scenario. Evaluation of bioclimatic suitability indices indicate increases in heat accumulation for all major winegrowing areas; including an increase of about 10% in growing-degree day, while morning low temperatures in September may experience increases of approximately 11% in the future, thus impacting negatively the ripening stage of grapevines and leading to changes in wine composition and quality. Additionally, the extent of areas classified under the cool to warm climate suitability categories could decrease by nearly 42% in the study area by 2050. Conditions in southern California are already warm and dry for viticulture and continuing heat accumulation increase, along with rainfall reduction, could potentially place additional stress to winegrape crop in the area, including advanced phenological timing and moisture deficit stress that could lead to decreases in yield. The projected decline in viticulture suitability highlights the need for adaptive capacity within this sector to mitigate the impacts of global warming. Possible mitigating strategies include planting hotter climate grape varieties, moving vineyards to regions that are more suitable in the future, and adopting dry-farming techniques.