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<p>Shortwave cloud radiative effects (SWCREs), defined as the difference of the shortwave radiative flux between all-sky and clear-sky conditions at the surface, have been reported to play an important role in influencing the Earth's energy budget and temperature extremes. In this study, we employed a set of global climate models to examine the SWCRE responses to <span class="inline-formula">CO₂</span>, black carbon (BC) aerosols, and sulfate aerosols in boreal summer over the Northern Hemisphere. We found that <span class="inline-formula">CO₂</span> causes positive SWCRE changes over most of the NH, and BC causes similar positive responses over North America, Europe, and eastern China but negative SWCRE over India and tropical Africa. When normalized by effective radiative forcing, the SWCRE from BC is roughly 3–5 times larger than that from <span class="inline-formula">CO₂</span>. SWCRE change is mainly due to cloud cover changes resulting from changes in relative humidity (RH) and, to a lesser extent, changes in cloud liquid water, circulation, dynamics, and stability. The SWCRE response to sulfate aerosols, however, is negligible compared to that for <span class="inline-formula">CO₂</span> and BC because part of the radiation scattered by clouds under all-sky conditions will also be scattered by aerosols under clear-sky conditions. Using a multilinear regression model, it is found that mean daily maximum temperature (<span class="inline-formula"><i>T</i>_max</span>) increases by 0.15 and 0.13&thinsp;<span class="inline-formula">K</span> per watt per square meter (<span class="inline-formula">W m⁻²</span>) increase in local SWCRE under the <span class="inline-formula">CO₂</span> and BC experiment, respectively. When domain-averaged, the contribution of SWCRE change to summer mean <span class="inline-formula"><i>T</i>_max</span> changes was 10&thinsp;%–30&thinsp;% under <span class="inline-formula">CO₂</span> forcing and 30&thinsp;%–50&thinsp;% under BC forcing, varying by region, which can have important implications for extreme climatic events and socioeconomic activities.</p>