ISSN / EISSN : 0936-577X / 1616-1572
Published by: Inter-Research Science Center (10.3354)
Total articles ≅ 1,732
Latest articles in this journal
Climate Research, Volume 84, pp 197-214; https://doi.org/10.3354/cr01657
Atmospheric rivers (ARs) are filamentary channels of high water vapor flux that transfer moisture horizontally through the atmosphere at low levels. ARs are often responsible for large annual rainfall totals as well as high-intensity storms due to orographic forcing. ARs are important features when predicting hazardous events such as flooding and are vital components of many regional water budgets. This is especially true for drought-prone areas such as southern California (SCA), which experiences relatively few storms per season, many from AR events. Here, we use a Lagrangian model to create backward air parcel trajectories of 159 AR events that made landfall on the US west coast from December 2004 to December 2015. Trajectories are used to examine the lifecycles and movements of these ARs and to differentiate ARs that made landfall in different regions. Prior to landfall, SCA ARs share similarities to but also have distinct differences from other ARs. At 1000 m above mean sea level (MSL), SCA AR trajectories travel shorter distances over the same 72 h time frame than trajectories for ARs that made landfall farther north. Additionally, along-trajectory measurements for SCA ARs tend to be warmer and have higher specific humidity values. This applies to both the 1000 and 2000 m MSL levels. These results imply that SCA ARs move slower and have the potential to produce higher intensity storms at landfall. An analysis of a case study event of an extreme AR that made landfall in SCA on 17 February 2017 confirms these results.
Climate Research, Volume 84, pp 181-195; https://doi.org/10.3354/cr01669
One way to estimate solar resources required by the solar industry is via regional climate models (RCMs), which provide a comprehensive and physically based state-of-the-art description of the atmosphere and its interactions with the Earth’s surface. Here we describe the first application of RCM simulations with Regional Climate Model Version 4 (RegCM4) for radiation fluxes over the South West Indian Ocean (SWIO). We analyzed the performance of RegCM4 on radiation fluxes, especially its radiative schemes presentation, which could provide basic information for surface solar radiation temporal-spatial variability analysis with RegCM4 over SWIO region. We used ERA-Interim reanalysis data for the period 2000-2005 to drive RegCM4 to simulate the radiation budget and associated parameters such as cloud cover, precipitation and surface temperature, over Southern Africa and the SWIO with a horizontal resolution of 50 km. The 2 existing available radiation schemes were tested and evaluated: (1) the default radiation scheme of the NCAR Community Climate Model Version 3 (CCM); and (2) the recently implemented Rapid Radiation Transfer Model (RRTM). To analyze the behavior of the radiation schemes and their impact on the surface climate, model outputs were validated against available satellite and reanalysis data. A comparison of the seasonal radiation budget as simulated by RegCM4-CCM and RegCM4-RRTM at the surface and at the top of the atmosphere showed good qualitative agreement. RegCM4 with the RRTM scheme generally better simulates the radiation budget and cloud cover over the whole domain with regard to the reference data than RegCM4 with the CCM scheme; RRTM could therefore be chosen as the radiative scheme in subsequent studies of surface solar radiation by RegCM4.
Climate Research, Volume 84, pp 145-158; https://doi.org/10.3354/cr01661
The impacts of climate change on industrial water demand (IWD) directly affect IWD management. In this study, we propose a framework for evaluating different impacts of climate change on IWD by sector, considering both direct and indirect effects. Data from 34 industrial sectors in Hebei Province, China, showed that the impacts of climate change varied by sector, and IWD in 22 of the 34 sectors was affected, ranging from -15.11 to 37.36% under the average rates of change in precipitation and temperature. The corresponding volumetric change of IWD was between -31.148 and 141.890 million m3, considering the difference in the water demand scale between sectors. The overall impact of climate change on IWD gradually decreased from more than 12.8% to approximately 4.1% from 2007 to 2016 due to the substantial improvement of water use efficiency. The indirect effects caused by the total industrial output value offset about 60-50% of the direct growth impacts. By contrast, the increase in IWD caused by the rise in temperature accounted for nearly 90% of the change, whereas only approximately 10% was caused by the decrease in precipitation. In general, an industrial sector may be directly and indirectly affected by temperature and precipitation, and the different impacts may offset each other. This study provides evidence and explanations for the heterogeneity of climate change impacts, and the research results can provide information for regional industrial water resource managers to adapt to climate change.
Climate Research, Volume 84, pp 159-179; https://doi.org/10.3354/cr01664
Large-scale moisture fluxes and backward air mass trajectories and frequencies were investigated to explain the mechanisms of synoptic-scale seasonal variability of air masses in the Mediterranean basin. For this aim, reanalysis data were used to calculate variations in moisture flux with respect to temperature and stability according to the 8 standard pressure levels between 1000 and 300 hPa. Investigating air mass characteristics changing with pressure levels provided new information in terms of air mass climatology for the Mediterranean basin. Results show that due to the influence of westerly flows, the Atlantic is the main source of moisture higher than 700 hPa. Turbulent transport of moisture from the Mediterranean Sea is the source of moisture close to the surface, which corresponds to levels lower than 700 hPa. According to the trajectory analysis, the continental Arctic (cA) air mass can reach the Mediterranean basin and provide very wet conditions over the Mediterranean basin during winter. In addition, during very dry conditions in summer, all air mass currents originate from surface pressure levels between 1000 and 850 hPa. These relatively warm and dominant air masses cause cloud-free conditions with very low precipitation over the Mediterranean basin. This study showed that air masses should be analyzed not only according to their source and path but also according to pressure levels. Therefore, more studies are needed investigating the contemporary air mass climatology of a specific region.
Climate Research; https://doi.org/10.3354/cr01653
Ecosystems are currently experiencing rapid changes. Decision-makers need to anticipate future changes or challenges that will emerge in order to implement both short-term actions and long-term strategies for reducing undesirable impacts. Strategic foresight has been proposed to help resolve these challenges for better planning and decision-making in an uncertain future. This structured process scrutinizes the options in an uncertain future. By exploring multiple possible futures, this process can offer insights into the nature of potential changes, and thereby to better anticipate future changes and their impacts. This process is performed in close partnership with multiple actors in order to collect broader perspectives about potential futures. Through a large research initiative, we applied the strategic foresight protocol to a set of different case studies, allowing us as academic ecologists to reflect on the circumstances that may be influential for the success of this approach. Here, we present what worked and what did not, along with our perception of the underlying reasons. We highlight that the success of such an endeavour depends on the willingness of the people involved, and that building social capital among all participants involved directly from the start is essential for building the trust needed to ensure an effective functioning among social groups with different interests and values.
Climate Research, Volume 84, pp 113-131; https://doi.org/10.3354/cr01662
Summer Arctic cyclones occur frequently in the Arctic Ocean and play an important role in sea ice variability. We used a reanalysis dataset and sea ice concentration data to identify and track summer great Arctic cyclones and to quantitatively analyse the contribution of cyclones to variations in sea ice concentration and area. We further explored the process of how cyclones influence sea ice via sea surface temperature, radiation, sea ice motion and ice deformation. The results indicate that cyclones accelerate decreases in sea ice concentration and area. The higher the values of the sea ice concentration index (ratio of maximum variation in sea ice concentration change rate to the minimum value of sea ice concentration change rate caused by the cyclone) and sea ice area responsivity (ratio of sea ice area change caused by cyclones to total sea ice area change) are, the greater is the contribution of cyclones to sea ice reduction. Over time, sea ice concentration decreases, and the impacts of cyclones on sea ice concentration are enhanced. During summer great cyclones, a strong low-pressure system and wind stress lead to increases in sea ice motion, ice divergence and changes in sea surface temperature and net radiation, promoting decreases in sea ice concentration and area. This study aids in the prediction of short-term sea ice change, and is beneficial to the development of coupled atmosphere-ocean-ice models.
Climate Research, Volume 84, pp 133-144; https://doi.org/10.3354/cr01663
The El Niño-Southern Oscillation (ENSO) in the preceding winter (December-January-February) is one of the key factors affecting subsequent East Asian summer (June-July-August) rainfall (EASR). However, current models face great challenges in reproducing ENSO’s impact on the EASR. This study attempts to reveal the factors that determine whether a model in phase 6 of the Coupled Model Intercomparison Project (CMIP6) can successfully reproduce this relationship by analyzing the outputs of historical climate simulation in 20 CMIP6 models. The results show that most of the models that overestimated ENSO interannual variability reproduced significant ENSO-EASR relationships, whereas all models that underestimated ENSO variability failed to reproduce this relationship. Further analyses show that models with stronger ENSO variability tended to simulate more realistic physical processes linking ENSO and EASR, i.e. the connections between ENSO and the tropical Indian Ocean (TIO) sea surface temperature (SST), between TIO SST and the Philippine Sea convection (PSC), and between PSC and EASR. Moreover, among the models that overestimated ENSO variability, only those that successfully captured significant TIO SST-PSC connections reproduced the observed ENSO-EASR relationship, although all these models captured ENSO-TIO SST and PSC-EASR teleconnections well. Therefore, simulating stronger ENSO interannual variability is the first necessary precondition for a CMIP6 model to capture the delayed effect of ENSO on EASR; reproducing a realistic TIO SST-PSC teleconnection is the second necessary precondition. This study will help models to improve their skills in simulation and prediction of EASR.
Climate Research; https://doi.org/10.3354/cr01656
Achieving sustainable harvesting of natural populations depends on our ability to predict population responses to the combined effects of harvesting and environmental fluctuations while accounting for other internal and external factors that influence population dynamics in time and space. Here, we review recent research showing how spatial patterns and interspecific interactions can influence population responses to harvesting in fluctuating environments. We highlight several pathways through which harvesting can, often inadvertently, influence the dynamics and resilience to environmental fluctuations of both harvested and surrounding non-harvested populations and species. For instance, spatial models have shown that harvesting is expected to influence the spatial synchrony of population fluctuations, both of the harvested species and its competitors, predators and prey, with implications for population extinction risk. Dispersal and interspecific interactions can cause responses to harvesting in areas and species that are not themselves harvested. Harvesting that selectively targets certain groups of individuals, either intentionally or through for example spatially biased harvesting, can amplify environmentally induced population fluctuations by biasing the population structure towards individuals that are more sensitive to environmental variation. On the other hand, harvesting can in some cases buffer populations against the density-dependent effects of harsh climatic conditions, which are probably more common than previously acknowledged. Recent advances in modeling are providing new predictions that are highly relevant under global warming and now need to be tested empirically. We discuss how knowledge of these pathways can be used to increase the sustainability of harvesting.
Climate Research, Volume 84, pp 75-95; https://doi.org/10.3354/cr01655
We investigated the time evolution of heat waves and warm nights over the 7 agro-climatic zones of Tamil Nadu, India, during the period 1951-2016, including the spatiotemporal patterns of concurrent hot day and hot night (CHDHN) episodes and the concurrent warm spells in daytime temperature and drought (CWD) episodes. The research relied upon gridded temperature and rainfall observations from the India Meteorological Department. We used the Heat-Wave Magnitude Index daily to study the warm spells in daytime and nighttime temperature, while the analysis of droughts was based on the Standardized Precipitation Evapotranspiration Index. We observed a considerable increase in the count, intensity and duration of heat waves and warm night episodes across Tamil Nadu between the periods 1951-1983 and 1984-2016. Particularly, the number of heat wave events almost doubled in the second half of the study period. We observed a west-east gradient in the severity of heat waves. The intensity and duration of warm night events increased up to 3-fold in the second half of the study period, especially over central Tamil Nadu. The study recorded a multi-fold increase in the number and frequency of CHDHN episodes and the number of CWD episodes during 1984-2016 compared to the base period 1951-1983. More importantly, the incidence of compound events that coexisted with anomalous phases of sea surface temperatures registered a statistically significant spike in many locations. These changes in temperature-induced extremes pose an exceptional public health threat that can increase morbidity and mortality, disproportionately affecting vulnerable sections of Tamil Nadu’s populace engaged in outdoor work.
Climate Research, Volume 84, pp 59-73; https://doi.org/10.3354/cr01659
Climate change can manifest in many ways, including impacts on the start, end, and duration of the frost-free season. We examined the climatology and variability of the first fall frost day (FFFD), last spring frost day (LSFD), and length of the frost-free season (LFFS) across Iran for the period 1978-2017. Trend analysis revealed that FFFD shifted later by 6.4 d over the study period while LSFD shifted earlier by slightly over 2 wk, and LFFS is now >3 wk longer than it was only 4 decades ago. Since land-use changes around meteorological stations may affect the temperature measured at these stations (especially the magnitudes of nocturnal cooling rates), atmospheric thickness changes, which reflect temperature changes and are independent of station-based measurements, were used as a secondary dataset to investigate minimum temperature trends. The analysis revealed a very strong relationship between frost-related indices and atmospheric thickness. Sequential Mann-Kendall statistical analysis revealed abrupt changes in the applied frost-related indices, minimum temperatures, and atmospheric thicknesses. The first abrupt changes in FFFD and LFFS occurred around 1996, which matched the timing of abrupt changes in atmospheric thickness over Iran. Interestingly, seasonal trend analyses of minimum temperature over the Northern Hemisphere using Era5 reanalysis data indicated consistent regional patterns of warming over the last 4 decades. The results suggest that the increase in LFFS is largely driven by regional-scale warming as opposed to local urbanization and/or land-use changes. Our results document an important and ongoing change of potentially considerable interest to agriculturalists in Iran and elsewhere.