Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title><jats:p>Globally, clouds are known to warm the climate system in the thermal infrared because they typically emit thermal radiation to space at effective temperatures lower than the combined cloud‐free atmosphere and surface. However, here we show that ∼40% of low‐level clouds over sea ice tend to cool the Arctic system at TOA and contribute to a radiative cooling of the Arctic winter climate by −2.3 Wm<jats:sup>−2</jats:sup>, or a ∼16% reduction over the infrared warming effect of all clouds during winter. Based on satellite observations, low‐level clouds residing in surface‐based temperature inversions emit more longwave radiation to space than would occur in cloudless skies. While these clouds are known to significantly warm the surface, they cool the Arctic climate system overall. Our results imply that accurately representing the cloud radiative effects unique to the Arctic could help to constrain the regional energy budget.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Slow slip events (SSEs) are important for the slip budget along a megathrust fault. Although the recurrence of weeks‐long short‐term SSEs (S‐SSEs) in southcentral Alaska has been suggested, a large amount of noise prevented us from detecting discrete events. We applied a systematic detection method to Global Navigation Satellite System data and detected 31 S‐SSEs during the 14‐year analysis period. The events mainly occurred at a depth from 35 to 45 km at a down‐dip extension of the 1964 Alaska earthquake, and the active clusters correlated with the region of the subducting Yakutat microplate. A large cumulative slip of S‐SSEs indicated a significant contribution to stress transfer along the plate interface, and its source area spatially coincided with that of the long‐term SSEs and the afterslip of the 1964 earthquake. Large and recurrent S‐SSEs are key phenomena for understanding interplate slip kinematics in this region.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Groundwater springs in permafrost regions provide pathways for solutes and dissolved gases to escape from sub‐permafrost groundwater systems, which otherwise are completely isolated from the surface environment and atmosphere. Yet, fundamental questions as to the mechanisms driving groundwater flow to the surface remain unsolved. In this study, basal permafrost aggradation is explored as a mechanism for generating groundwater flow and driving groundwater spring systems. We employ process‐based numerical modeling to test the hypothesis of permafrost‐aggradation‐driven spring systems in a range of environmental settings. The model results show that permafrost aggradation can generate spring flow on a multi‐millennial timescale and with discharge rates up to a couple of liters per second. Permafrost aggradation deserves attention as a groundwater flow driving mechanism in areas of recent glacio‐isostatic uplift and glacial retreat.</jats:p>

<jats:title>Abstract</jats:title><jats:p>In August 2022, the Tohoku region of Japan suffered three major heavy rainfall events, while one was related to an anticyclone, and the others were induced by a “Baiu‐like” stationary front. By using the Lagrangian backward trajectories, we found the moisture sources of the three events varied much due to the rapidly changing atmospheric conditions. In general, moisture from the Sea of Japan contributed the most in all events, while the western Pacific also played a certain role. Surprisingly, moisture from tropical storms and the East China Sea did not contribute much due to the along‐transport precipitation. But, based on forward‐traced trajectories, we confirmed that tropical storms did enhance moisture transport from subtropical regions via their southerly wind. Overall, this study highlights the role of the moisture gains nearby and the outer flows of tropical storms during heavy rainfalls in a northern region.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Compound drought‐heatwave (CDHW) events threaten ecosystem productivity and are often characterized by low soil moisture (SM) and high vapor pressure deficit (VPD). However, the relative roles of SM and VPD in constraining forest productivity during CDHWs remain controversial. In the summer of 2022, China experienced a record‐breaking CDHW event (DH2022). Here, we applied satellite remote‐sensing data and meteorological data, and machine‐learning techniques to quantify the individual contributions of SM and VPD to forest productivity variations and investigate their interactions during the development of DH2022. The results reveal that SM, rather than VPD, dominates the forest productivity decline during DH2022. We identified a possible critical tipping point of SM below which forest productivity would quickly decline with the decreasing SM. Furthermore, we illuminated the evolution of SM, VPD, evapotranspiration, forest productivity, and their interactions throughout DH2022. Our findings broaden the understanding of forest response to extreme CDHWs at the ecosystem scale.</jats:p>

<jats:title>Abstract</jats:title><jats:p>A decline of anthropogenic aerosol (AA) emission is expected worldwide over the coming decades. But the climate effects of aerosol removal and greenhouse gases (GHG) emission at regional scale are poorly distinguished and constrained. Taking the Tibetan Plateau (TP) as an instance, analyses of the state‐of‐the‐art climate models participating in the Detection and Attribution Model Intercomparison Project imply that while the observed warming from 1961 to 2020 is predominantly attributed to GHG emission, the future temperature rise will be influenced by the combined effects of persistent increase in GHG concentration and reduction of AA emission. Here, we develop a new constraint method considering the changed contribution of AA forcing. Constrained by detected individual external forcings, the joint contributions of GHG (1.74°C) and AA forcings (0.10°C) will lead to a warming around 1.85°C over the TP during mid‐century (2041–2060) relative to 1995–2014 under SSP2‐4.5 scenario, which is 0.44°C cooler than the raw projection.</jats:p>

<jats:title>Abstract</jats:title><jats:p>A more accurate representation of ice‐phase processes in numerical models necessitates an enhanced understanding of ice‐particle microphysics and their respective formation conditions. Prior in situ measurements have noted distinctive ice‐particle shape characteristics associated with different cloud systems and geographical locations. The recent advancement in ice‐particle backscattering theories enables a more comprehensive exploration of the geographical distribution and seasonal dependence of ice‐particle shape categories than ever before. This exploration is being undertaken for the first time using space‐borne lidar measurements. Distinct geographical preferences were observed for five different ice‐particle categories. Bullets/rosettes were the most common, followed by Voronois, which were especially prevalent in high‐level tropical clouds, and 2D columns, which were commonly found in mid‐ and low‐level clouds. Droxtals were primarily observed in high‐level subtropical regions. The global distribution of ice‐particle types provides valuable insights into the physical processes related to ice cloud particle shape formation, cloud duration, and radiative impacts.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Taking advantage of the Polar Amplification Model Intercomparison Project simulations and using a Lagrangian objective feature tracking algorithm, we determine the response of extratropical cyclones to sea‐ice loss and consequent weakening of the equator‐to‐pole near‐surface temperature gradient. The wintertime storm tracks are found to shift equatorward in the North Atlantic and over Europe, and eastward in the North Pacific. In both regions, cyclones become weaker and slower, particularly on the poleward flank of the storm tracks. On average, there are fewer individual cyclones in the extratropics each winter, they last longer, are weaker, and travel more slowly. These changes are greatest over the Arctic, but still statistically significant in midlatitudes despite being small compared to internal variability. Inter‐model spread in cyclone responses are not strongly correlated with that in Arctic warming or Arctic amplification. Little change in summertime cyclones is found.</jats:p>

<jats:title>Abstract</jats:title><jats:p>We derive the ALOS‐2 coseismic interferograms, pixel‐offsets and Sentinel‐2 sub‐pixel offsets of the 2023 <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.8 and <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.7 Kahramanmaras, Turkey earthquake sequence. Offset maps show that the sequence ruptured ∼300 km along the East Anatolian Fault (EAF) and ∼180 km along the secondary Cardak and Dogansehir faults. We infer the coseismic slip distribution and interseismic fault motion by inverting the co‐ and inter‐seismic observations. Inversion results show that the coseismic slip (∼8.0 m) and interseismic strike‐slip rate (∼4.6 mm/yr) on the main rupture of the <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.8 event are basically consistent with the ∼8.4 m and ∼3.9 mm/yr of the <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.7 event. Most coseismic slips of the <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.8 and <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.7 events occur within 10 and 12 km at depth, respectively, in keeping with the interseismic locking depth of 10.4 ± 3.3 km and 11.1 ± 3.1 km. This implies that the coseismic rupture kinematics correlate with the interseismic strain accumulation. Moreover, static stress changes show that the <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.7 event is likely promoted by ∼2 bar stress increase from the <jats:italic>M</jats:italic><jats:sub><jats:italic>w</jats:italic></jats:sub>7.8 event on the central section of its main rupture.</jats:p>

<jats:title>Abstract</jats:title><jats:p>In boreal winter, the El Niño/Southern Oscillation (ENSO)‐induced Pacific‐North American (PNA) teleconnection pattern is farther westward during La Niña relative to that in El Niño, causing discernible distinct climate implications. However, there has been a lack of consensus regarding the underlying mechanism driving this asymmetric structure. This study highlights the contribution of nonlinear kinetic energy advection (nKA) to this asymmetry. The zonally symmetric responses to ENSO, specifically the anomalies in zonal mean zonal flow, generate opposing nKA patterns by advecting anomalous eddy kinetic energy in the North Pacific, which leads to the shift of the PNA teleconnection pattern. In addition to nKA, transient eddy activities responded to changes of baroclinicity help maintain the asymmetry through a feedback effect. These findings underscore the importance of considering extratropical factors, such as nonlinear energy processes and synoptic‐scale transient eddies, in understanding the mechanism responsible for the asymmetric structure of the PNA teleconnection pattern.</jats:p>