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Compound climate events can significantly impact vegetation productivity, yet the direct and lagged vegetation productivity responses to seasonal compound warm-dry and cold-dry events remain unclear. Using observationally-constrained and process-based model data, we analyze vegetation productivity responses to the compound conditions of precipitation and temperature in spring and summer. Our results show the regional asymmetries in direct and lagged effects of compound warm-dry events. In high-latitudes (>50°N), compound warm-dry events raise productivity. In contrast, in mid-latitudes (23.5-50°N/S), compound warm-dry events reduce productivity and compound warm-dry springs can cause and amplify summer droughts, thereby reducing summer productivity. Moreover, compound cold-dry events impose directly and indirectly adverse synergistic effects on productivity in mid-to-high latitudes and their effects exceed individual cold and dry impacts. Our results highlight that a multivariate perspective is necessary to appropriately investigate the impacts of climate extremes on vegetation productivity as precipitation and temperature often covary.

With the global climate change and the rapid expansion of urban land use, urban storms and floods have occurred frequently. The state has gradually attached importance to the unified construction of low-impact development facilities (LID) and underground integrated pipe corridors (GL), which makes sponge city both beautiful and practical. In order to study the urban hydrological response of the combination between LID and underground integrated pip corridors (LID_GL), the Yangmei River Basin, a pilot area of ​​Guangzhou's integrated pipe corridors, was taken as an example to evaluate and compare the hydrological response of traditional development, GL, LID, GL_LID scenarios. The results show that:(1) The traditional development scenario is verified by the measured rainfall of “2018.06.08”. The simulation results are consistent with the areas where are liable to waterlogging under the actual circumstance, which proves that the SWMM model is suitable for the hydrological response evaluation of LID_GL scenario in the Yangmei River Basin. (2) The SUSTAIN model can realize the optimized layout of LID, but the simulation accuracy needs to be improved. On the contrary, the SWMM model cannot realize the LID optimized layout, but the simulation accuracy of urban hydrological response is high. To Combine their advantages, the LID optimized layout schemes calculated by SUSTAIN model are input into SWMM model for hydrological simulation. The results show that this method can avoid the situation that the evaluation results are irrational due to improper layout of LID. (3) The overflow reduction in the LID_GL scenario is best, which can exceed 60% under high-return-period rainfall conditions. Its peak outlet flow is lower than GL scenario and the peak appearance time is also delayed. The above research results can provide reference and theoretical support for the unified construction of LID and underground integrated pip corridors (LID_GL) in the future.