Cities are characterized by an urban overheating which, combined to more frequent and intense heatwaves caused by climate change, expose the city dwellers to an increasing human thermal stress. Street trees may partially mitigate overheating by means of cast shadows and transpiration, two processes which may depend on their morphological and physiological characteristics. At the same time, periods of severe water shortage are multiplying and the ability of street trees to thrive and maintain significant cooling benefits under heat and drought conditions is crucial. In order to improve the understanding of the factors influencing tree climatic benefits, a methodology based on the monitoring of the interactions along the soil-tree atmospherecontinuum in two complementary experimental facilities was developed. On the one hand, a 1/5 scale canyon street, partially planted with young potted drip-irrigated ornamental apple trees (Malus Coccinella® ‘Courtarou’) located in Angers, France was monitored to quantify the effect of street trees experiencing different water supplies on the microclimate. On the other hand, an in-situ monitoring of the microclimate inside and outside the canopy for 36 mature street trees from 9 different tree species located in 5 sites in Paris, France, was performed. On the basis of a detailed cross-analysis of these two experimental facilities, an integrated assessment of the street trees climatic benefits was proposed to explore the sources of variability of the climatic benefits provided by trees and help stakeholders understand the relationship between drought resistance and human thermal stress mitigation for different tree species.