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Great difficulty in characterizing the spatial pattern and scale of regional surface urban heat islands (RSUHIs) over urban agglomerations is mainly attributed to the RSUHI extent exceeding urban boundaries and strong variations in the background climate state and land cover. A new method that successfully addresses these problems by applying the spatial similarity of the land surface temperature (LST) annual cycle in urban agglomerations is proposed to characterize the RSUHI spatial pattern and scale in the Yangtze River Delta of China. This method has good adaptability to complex terrain and climate variations and simultaneously identifies the RSUHI spatial pattern and scale. The RSUHI spatial extent averaged 3.7 × 104 km2 in 2003–2020, which is 1.5–2.0 times the urban extent, and had a fluctuating but increasing tendency. Rapid urbanization and the spatial pattern‐shifting LST anomalies were mainly responsible for the fluctuating RSUHI extent during 2003–2020. Plain Language Summary: In contrast with a single city, urban agglomerations can create regional urban heat islands and threaten environmental sustainability, biodiversity, and resource and energy consumption on a regional scale. Accurately quantifying the spatiotemporal variations of regional urban heat islands is of practical importance to urban planning and environmental management in terms of shaping rational urban clusters, mitigating heat‐related health risks and improving human comfort in urban agglomerations. We propose a new method that reasonably identifies the urban–rural cliff of the land surface temperature in urban agglomerations using a spatial similarity algorithm, and we simultaneously identify the spatial pattern and scale of regional urban heat islands in the Yangtze River Delta of China. The proposed method has great potential in mitigating heat‐related health risks and improving urban design owing to its good adaptability to complex terrain, land cover and climate variations. Key Points: Rapid urbanization leads to strong differences in the annual cycle of the land surface temperature (LST) between urban and nonurban areasA new method based on the similarity of annual cycles of the LST is proposed to quantify regional heat island effectsThis method adapts well to complex terrain, land‐cover changes and climate variations and has great potential in urban planning [ABSTRACT FROM AUTHOR]

The Ross Sea has the world's largest marine protected area. Modified Circumpolar Deep Water (MCDW) has significant effects on physical and biological processes in the Ross Sea. Totally 13 penguin ornithogenic sediment profiles were collected from Inexpressible Island, Ross Sea, and the Cd/P ratios were used as a proxy of MCDW intrusion, enabling to reconstruct the variability of MCDW intrusion into the Ross Sea during the past 6,000 years. During the intervals of ∼0.7–1.6 and ∼2.8–6.0 kyr BP, enhanced MCDW intrusion increased the heat supply which warmed the surface water and reduced the coastal sea ice concentration. By contrast, reduced MCDW intrusion during ∼1.6–2.8 kyr BP caused a decrease in the penguin population via restricting food supply and/or increasing sea ice concentration. Thus, changes in MCDW were responsible for driving millennial changes in sea ice and penguin population in the Ross Sea. Plain Language Summary: Modified Circumpolar Deep Water (MCDW) has important impacts on physical and biological processes in the Ross Sea. Although high‐resolution spatiotemporal records of MCDW intrusion into the modern Ross Sea have been obtained using various methods, the intrusion of this water mass into the Ross Sea during the Holocene has not previously been reconstructed. Here, we use measurements of the Cd/P ratio in ornithogenic sediments to reconstruct the variability of the intrusion of the MCDW into the Ross Sea during the past 6,000 years. MCDW intrusion was enhanced during the intervals of ∼0.7–1.6 and ∼2.8–6.0 kyr BP, when the resulting increased heat supply warmed the surface water and reduced the concentration of coastal sea ice. By contrast, when MCDW intrusion was reduced during ∼1.6–2.8 kyr BP, the resulting restriction of the food supply and/or increased coastal sea ice concentration caused a decrease in the penguin population. Our results demonstrate that the Cd/P ratio can be used as a proxy of MCDW intrusion and that changes in the intrusion of the MCDW were responsible for driving millennial‐scale changes in sea ice and the penguin population in the Ross Sea. Key Points: Cd/P profiles from ornithogenic sediments can be used as a proxy of Modified Circumpolar Deep Water (MCDW) intrusionReconstruction of MCDW intrusion in the Ross Sea during the past 6,000 yearsMCDW intrusion drives millennial changes in sea ice concentration and penguin population in the Ross Sea [ABSTRACT FROM AUTHOR]

The impact of climate and weather on penguin ecology has attracted much research attention. To reconstruct the history of the penguin population, penguin carcasses on the surface and three ornithogenic sediment profiles were collected in a ditch area beneath abandoned penguin subcolonies on a high terrace to the northwest of the modern colony in Seaview Bay, on Inexpressible Island, East Antarctica. A rapid increase in penguin‐derived element contents in the sediment profiles at ~1700 Common Era (CE) indicates an increase in the penguin population of research area at the end of the Little Ice Age. However, surficial carcasses, geochemical characteristics of the sediment profiles, and field evidence indicate the subsequent abandonment of these penguin subcolonies. A period of intensified streamflow activity resulting from meltwater is a possible explanation for the colony abandonment. The dating results of the carcasses and sediment profiles constrain this event to around the late nineteenth century. The meltwater streams can be attributed to the interaction between enhanced moist air mass transport to the coastline of Victoria Land, rising temperatures, and the sloping topography. Comparisons with other regional records suggest that this type of event is common across East Antarctica and has significant impacts on penguin ecology. Key Points: Reconstruction of penguin population changes in an area of abandoned subcolonies in Inexpressible Island (to the northwest of Seaview Bay), during the last three centuriesPenguin population in the research area increased during the late Little Ice AgePenguin subcolonies in the research area were abandoned in the late nineteenth century [ABSTRACT FROM AUTHOR]

Analysis of ground‐based and remotely retrieved precipitation data reveals that heavy Meiyu precipitation events (HMPEs) produce a relatively independent rain belt over eastern China. A rotating calipers algorithm is applied to quantify the spatial scales of HMPEs. We find that HMPEs have regular spatial scales with an average length, width, and extent of about 1,400 km, 500 km, and 40.00 × 104 km2, respectively, through a comprehensive assessment of different types of HMPE, illustrating that HMPEs have a size similar to that of the subsynoptic‐scale Meiyu front (1,500–2,000 km). Convective activities along the Meiyu front zone and the upper westerly jet stream strongly affect the position and orientation of rain belts of HMPEs. The Meiyu front zone, strong vertical motions, and large transport of warm moisture have a comparable spatial scale to the HMPE rain belts over eastern China. Plain Language Summary: Many studies have revealed that extreme precipitation events of short or long duration have highly varying spatial scales from several hundred kilometers to several thousand kilometers, increasing the difficult of identifying the most flood‐related precipitation events and corresponding important atmospheric processes. We used a rotating calipers algorithm to quantify the length, width, position, and orientation of rain belts and found that flood‐related heavy Meiyu precipitation events with strong intensity, long duration, and large area have regular climatological spatial scales. Our results will benefit flood‐risk management and decision making for the Yangtze River Basin in China. Key Points: Flood‐related heavy Meiyu precipitation events have robust climatological spatial scales over eastern ChinaAn upper westerly jet stream and lower Meiyu front steer the position and orientation of rain belts of heavy Meiyu precipitation eventsConvective activities along the Meiyu front zone have a comparable spatial scale to the rain belt of heavy Meiyu precipitation events [ABSTRACT FROM AUTHOR]

Many flooding-tolerant species are clonal plants; however, the effects of physiological integration on plant responses to flooding have received limited attention. We hypothesise that flooding can trigger changes in metabolism of carbohydrates and ROS (reactive oxygen species) in clonal plants, and that physiological integration can ameliorate the adverse effects of stress, subsequently restoring the growth of flooded ramets. In the present study, we conducted a factorial experiment combining flooding to apical ramets and stolon severing (preventing physiological integration) between apical and basal ramets of Cynodon dactylon, which is a stoloniferous perennial grass with considerable flooding tolerance. Flooding-induced responses including decreased root biomass, accumulation of soluble sugar and starch, as well as increased activity of superoxide dismutase ( SOD) and ascorbate peroxidase ( APX) in apical ramets. Physiological integration relieved growth inhibition, carbohydrate accumulation and induction of antioxidant enzyme activity in stressed ramets, as expected, without any observable cost in unstressed ramets. We speculate that relief of flooding stress in clonal plants may rely on oxidising power and electron acceptors transferred between ramets through physiological integration. [ABSTRACT FROM AUTHOR]