Preliminary Report; Abrupt temperature changes cause minor impacts on swimming and feeding performance in the sheepshead minnow (Cyprinodon variegatus)

Abrupt temperature changes and warming hiatuses have a great impact on socioeconomic systems; however, their mechanisms remain unclear. In this study, the quantitative mechanisms of the responses of abrupt seasonal temperature changes and warming hiatuses in China to their influencing factors were analysed using the monthly mean temperature (Tav), mean minimum temperature (Tnav), and mean maximum temperature (Txav) from 622 meteorological stations in China covering 1951–2018, the CMIP6 model data, and data at large spatial scales, including Atlantic multidecadal oscillation (AMO) data. The results showed that the contributions of the influencing factors to the abrupt changes in Tav, Tnav, and Txav showed large spatial variability and peaked in the spring and summer and bottomed out in the autumn. The Pacific decadal oscillation (PDO) greatly impacted the abrupt temperature changes in Northeast China and North China at a contribution rate of approximately 12%, strongly influenced the abrupt temperature changes south of the Yangtze River, and markedly influenced the abrupt temperature changes in Northwest China. The AMO had a large impact on temperature in most regions of China in all seasons except for the summer. The MEI mainly affected the abrupt seasonal temperature changes in the region between 25° N and 35° N. The Arctic oscillation (AO) substantially impacted the warming hiatuses in Northeast China in the winter at a contribution rate of approximately 12%. These influencing factors contributed less to warming hiatuses than to abrupt temperature changes. Among the regional influencing factors, AP and WS greatly impacted warming hiatuses, more so than abrupt temperature changes, while relative humidity (RH) and solar radiation (SR) contributed little to warming hiatuses.

The global climate shows an obvious warming trend, and the impact on water resources is increasing. Abrupt temperature change and warming hiatus are two important states of temperature change. The quantitative impacts of temperature change and warming hiatus on surface runoff remain unclear. Based on the measured runoff data from 60 representative hydrological stations in China from 1956 to 2016 and the Water Balance Model developed by the Research Center for Climate Change (RCCC-WBC), this paper analyzes the quantitative impacts of abrupt temperature change and warming hiatus on surface runoff. The results showed that the effects of three types of abrupt temperature changes on runoff in different basins in China are significantly different. The effects of abrupt temperature changes and warming stagnation on runoff in northern China are greater than those in southern China, and the effects of abrupt temperature changes and warming stagnation on runoff in the upper, middle, and lower reaches of the same basin are also different. Before the abrupt change in temperature, the influence of temperature on the surface runoff was less than 9%, and the influence of temperature on the runoff in some southern areas was weaker, only affecting less than 3% of the runoff. When the temperature changes abruptly, the influence of air temperature on the surface runoff in a small part of the arid region is up to 30%. The abrupt change in mean maximum temperature has both positive and negative driving effects on runoff in China, and the negative driving effect is concentrated in the areas with abrupt warming, affecting about 8% of the runoff on average. The average influence of abrupt mean temperature change on runoff in China is about 10%, and the area with a large influence on runoff change is concentrated in the area north of 40° N. The abrupt change in temperature in the middle and lower reaches of the Yellow River Basin has a great influence on the runoff change, up to 13%. The maximum impact of abrupt mean minimum temperature on runoff is concentrated in Northeast China, ranging from 9% to 12%. During the period of temperature stagnation, air temperature and runoff showed an obvious reverse trend. During this period, the average negative influence of drastic changes in air temperature on runoff was about 15%, but precipitation and runoff still maintained a good consistency, which may be due to the effect of other influencing factors which offset the negative driving effect of air temperature.

Abrupt temperature changes and warming (cooling) hiatuses have an impact on the ecological environment. Currently, research findings for the spatial variability in the years of abrupt temperature changes and warming (cooling) hiatuses covering a variety of climate zones, as well as the variation trends before and after these years, are lacking. In the present study, based on the seasonal (monthly) average minimum temperatures, average temperatures, and average maximum temperature data from 622 Chinese meteorological stations during 1951–2018, the spatial variability in the years of abrupt seasonal changes and warming (cooling) hiatuses for these three temperature types in China, as well as the variation trends before and after these years, were analyzed using the Mann-Kendall test. The results are as follows. For most stations in China, the abrupt changes in the three temperature types during each season began to occur over a wide range in the late 1980s and early 1990s, and abrupt changes did not occur at a few stations concentrated south of 30° N. After an abrupt change occurred, the average minimum temperatures and average temperatures both showed significant upward trends, while the average maximum temperatures showed significant downward trends in some regions of southern China. After five to 15 years of temperature increases (decreases) following the abrupt changes, warming (cooling) hiatuses occurred in some areas of China, with the hiatus years occurring between 1989 and 2013. These hiatuses mainly occurred in 1998 and 2007, and in terms of proximity, the stations without warming (cooling) hiatuses were concentrated south of 40° N. After nine to 17 years of warming (cooling) hiatuses, the hiatuses ended at some stations between 2013 and 2017, after which the temperatures again increased rapidly. The periods of warming (cooling) hiatuses were longer in northern China than in southern China. Currently, there are some stations where the hiatuses have not ended, suggesting that the hiatus period is apparently longer than 17 years. The years of abrupt change, no abrupt change, hiatus, no hiatus, end of hiatus, and no end of hiatus, as well as their variation trends before and after these years, have shown strong spatial variability. The results of this study have enriched the research findings on climate change.

Abrupt and gradual temperature changes influence on the climatic suitability of Northwestern Alpine grapevine-growing regions for the invasive grape leafhopper Scaphoideus titanus Ball (Hemiptera, Cicadellidae)

The abrupt temperature change (ATC) and warming hiatus (WH) phenomena impact global resources and the environment. However, information on the spatial and temporal variability in the ATC and WH over large regions, long time scales and densely distributed stations is lacking. In the study, based on average minimum, average and average maximum temperatures data from 1951 to 2016 from 622 meteorological stations in China, the spatial and temporal variability in the timing of the ATC and WH events and the characteristics before and after these events were revealed by using the Mann–Kendall test. In most areas of China, an ATC occurred in the three temperature parameters, and the onset of the changes occurred later at lower latitudes. The ATC in the average minimum temperature occurred earlier than that in the average temperature, and the ATC in the average maximum temperature occurred the latest. After the ATC, a WH occurred at most of the stations that experienced an increase in temperature, whereas a cooling hiatus (CH) did not occur at stations that experienced a decrease in temperature. The regions with decreasing temperatures were concentrated in the hilly and plain areas of southern China and in subtropical and tropical monsoon climate zones. The WH of the average temperature occurred earlier than that of the average maximum temperature, which occurred earlier than that of the average minimum temperature. Overall, the WH began later from east to west and was mainly concentrated in approximately 1998 and 2007. Both the ATC and the WH in the Qinghai–Tibet Plateau area showed hysteresis. The ATC to WH period was between three and 27 years, and the earlier the ATC was, the longer was the period. Before the ATC, all three temperature parameters increased slightly. The average minimum temperature rose faster than the average temperature, and the average maximum temperature rose the slowest. Furthermore, the variation became more dramatic from southeast to northwest. After the ATC, the temperatures in most areas increased rapidly, and the rate of temperature increase increased with decreasing latitude. The average maximum temperature decreased in the area east of 100° E and south of 30° N. In this area, the rates of temperature increase for the average minimum and average temperatures were on a par with the rate of decrease in the absolute average maximum temperature, with the rates being three to five times greater than those before the ATC, but without dramatic variations. After the ATC, a CH did not occur at the stations where the temperature had decreased, whereas a WH occurred after a certain period of time at most of the stations where the temperature had increased. Moreover, such occurrences differed with latitude. A comparison of the temperature after the WH with that both before and after the ATC but before the WH revealed that the temperature did not vary dramatically. Eight to 10 years after the WH, the temperatures at a small number of stations in northern China rose again; however, due to the short length of the time series, it is impossible to determine whether the WH had truly ended. The results of the study enrich the findings of climate change research and provide a reference for addressing resource and environmental issues.

Detection of abrupt change is a key issue for understanding the facts and trends of climate change, but it is also a difficult task in practice. The Mann-Kendall (MK) test is commonly used for treating the issue, while the results are usually affected by the correlation and seasonal characters and sample size of series. This paper proposes a discrete wavelet entropy-aided approach for abrupt change detection, with the temperature analyses in the Haihe River Basin (HRB) as an example. The results show some obviously abrupt temperature changes in the study area in the 1960s–1990s. The MK test results do not reflect those abrupt temperature changes after the 1980s. Comparatively, the proposed approach can detect all main abrupt temperature changes in HRB, so it is more effective than the MK test. Differing from the MK test which only considers series’ value order or the conventional entropy which mainly considers series’ statistical random characters, the proposed approach is to describe the complexity and disorderliness of series using wavelet entropy theories, and it can fairly consider series’ composition and characteristics under different scales, so the results can more accurately reflect not only the abrupt changes, but also the complexity variation of a series over time. However, since it is based on the entropy theories, the series analyzed must have big sample size enough and the sampling rates being smaller than the concerned scale for the accurate computation of entropy values.

Abrupt change of temperature and precipitation extremes in the arid region of Northwest China

PDF HTML阅读 XML下载 导出引用 引用提醒 长白山北坡不同海拔红松径向生长-气候因子关系对气温突变的响应 DOI: 10.5846/stxb201706171104 作者: 作者单位: 北京师范大学地理科学学部,北京师范大学地理科学学部 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（41630750） Response of the relationship between radial growth and climatic factors to abrupt change of temperature along an altitudinal gradient on the northern slope of Changbai Mountain, Northeast China Author: Affiliation: Department of Geographical Sciences, Beijing Normal University,Department of Geographical Sciences,Beijing Normal University Fund Project: The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:树木径向生长受复杂环境的影响。为预测气候变化背景下未来红松（Pinus koraiensis）径向生长动态变化，在长白山北坡采集3个海拔梯度（745、1134、1280 m）红松树轮样芯，运用树木年轮学研究方法，分析不同海拔红松径向生长-气候因子关系对气温突变的响应差异。结果表明：（1）通过对采样点附近气象站气温数据的M-K检验发现，年均温在1987年发生显著突变；（2）低海拔红松径向生长主要受当年生长季6-7月降水的影响，中、高海拔红松径向生长主要受当年7月平均最低气温的影响；（3）气温突变以后，低海拔红松径向生长-气候因子关系较为稳定，中海拔红松径向生长对前一年11月降水量的响应关系发生显著改变，高海拔红松径向生长对当年5月降水量的响应关系发生显著改变。因此，气温突变背景下，低海拔红松树轮年表更适用于区域气候重建等研究。同时随着气温持续升高，低海拔红松径向生长可能呈现下降趋势，中、高海拔红松径向生长可能呈现先增加后下降的趋势。 Abstract:The radial growth of trees is affected by complex environment. To predict the radial growth dynamics of Pinus koraiensis in the context of climate change, tree ring cores of P. koraiensis were collected from sampling sites at different elevations (745 m a.s.l., 1134 m a.s.l., and 1280 m a.s.l.) on the northern slope of Changbai Mountain. Using a dendrochronological method, we investigated the variability in the responses of radial growth to climatic factors and the temporal stability of the responses at different elevations. The results from the Mann-Kendall test showed that an abrupt change in annual mean temperature occurred in 1987. Tree growth at the low elevation was mainly influenced by the precipitation that occurred in June and July, whereas tree growth at the middle and high elevations was mainly affected by the mean minimum temperature of July. After the abrupt change in temperature, the growth-climate relationship was relatively stable at the low elevation; however, the response of radial growth to precipitation during November of the previous year at the middle elevation and to precipitation that occurred in May at the high elevation changed significantly. Therefore, in the context of an abrupt change in temperature, the chronology of P. koraiensis at low elevations is more suitable for the study of regional climate reconstruction. However, when the temperature continued to rise, the radial growth of P. koraiensis showed a downward trend at the low elevation, whereas at the middle and high elevations, tree growth first increased and then decreased. 参考文献 相似文献 引证文献

Based on the reanalysis data from the National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP–NCAR) and solar radio irradiance (SRI) at 10.7 cm wavelength obtained from the National Oceanic and Atmospheric Administration’s Space Weather Prediction center, the abrupt temperature change in the mid-1970s and its possible association with solar irradiance variability have been investigated. The results show that a discontinuous abrupt change in the mid-1970s in the NCEP–NCAR reanalysis was observed in the tropical lower and middle stratospheric temperature. The shift in temperature and its timing agrees well with the climate regime shift discovered in the radiosonde observations (HadAT), European Centre for Medium-Range Weather Forecasts Re-Analysis (ERA-40), and many previous studies and manifests a statistically significant change at the 95% confidence level. A corresponding change of the SRI was identified in the mid 1970s although the statistical t test value is not very high. The running correlation with a 21-year moving time window exhibits a strong positive correlation between the solar cycle and atmospheric temperature in the tropical stratosphere during the period of 1948–2007. However, the positive correlation was broken at the time of the mid-1970s abrupt change and two peak positive correlation points were observed in 1972 and 1982, respectively.

Estimation of groundwater velocity in localized fracture zones from well temperature profiles

The mechanism of the abrupt temperature change‐climate warming hiatus is not clear, and understanding the response relationships between it and the influencing factors is significant to the study the mechanism. Based on the annual average temperature (Tave), annual average minimum temperature (Tmin), and annual average maximum temperature (Tmax) of 622 meteorological stations in China from 1951 to 2018, the response relationships between the three temperatures and the influencing factors were analyzed. The results showed that In the periods before, during, and after an abrupt temperature change, For the abrupt changes in the three temperatures, the regions significantly influenced by the solar radiation (SR), AMO, multivariate El Niño southern oscillation (ENSO) index (MEI), and Pacific Decadal Oscillation (PDO) accounted for more than 80% of China, and for the abrupt changes in Tmin, the regions with significant influences covered the whole of China. The regions significantly influenced by the AO accounted for more than 60% of China, and the regions significantly influenced by the remaining factors accounted for more than 30% of China. The AO mainly influenced the abrupt temperature change in the northern regions, the AGG and CO2 mainly influenced all the regions except for Northeast China, and the influencing scopes of the atmospheric pressure (AP) were relatively small and not concentrated. In summary, when some conditions continued for a period and a tendency rate or value was reached, abrupt temperature change occurred, and the conditions were as follows: the AGG continued to increase, the PDO was in a positive phase, the AMO and SR continued to rise, the MEI changed abruptly, and the AP in each zone continued to decline/increase and experienced the subsequent trend change. In the periods before, during, and after the climate warming hiatus, few influencing factors had a significant correlation with the temperatures. The MEI and PDO influenced more than 80% of the regions that experienced the climate warming hiatus, and other factors influenced less than 60% of these regions. In the 1990s, especially after 1998, the increase in the AGG slowed, the PDO declined or was in a negative phase, the MEI and SR decreased, and the AP in each zone continued to decline/increase and experienced the subsequent trend change; when those conditions continued for a period and a tendency rate or value was reached, the climate warming hiatus occurred. The abrupt temperature change‐climate warming hiatus was the result of the joint action of multiple influencing factors.

Abstract. In the Northern Hemisphere, the last 16.5 kyr was characterized by abrupt temperature transitions during stadials, interstadials, and the onset of the Holocene. These changes are closely linked to large-scale variations in the extent of continental ice sheets, greenhouse gas concentrations, and ocean circulation. Speleothems and their fluid inclusions serve as valuable proxies, offering high-resolution chronologies and quantitative records of past temperature changes for understanding global and regional climate mechanisms in the past. Here, we present a record based on five speleothems from two caves on the northeastern Iberian Peninsula (Ostolo and Mendukilo caves). Using hydrogen isotopic composition of fluid inclusions and rainfall samples, we developed a δ2H/T transfer function in order to reconstruct regional temperatures over the past 16.5 kyr (Ostolo–Mendukilo Fluid Inclusion Temperature record, OM-FIT). Our novel findings reveal abrupt temperature changes in SW Europe during the last deglaciation and Early Holocene, at millennial and centennial scales, anchored by a precise chronology. At the onset of Greenland Interstadial 1, the OM-FIT record shows an increase of 6.7 ± 2.8 °C relative to the cold conditions of the preceding Greenland Stadial 2.1a. During the early phase of Greenland Stadial 1, OM-FIT records a temperature decline of 6.1 ± 2.8 °C. The end of this cold phase and the onset of the Holocene are marked by a rapid warming of about 5 °C, reaching a maximum at 11.66 ± 0.03 kyr BP. The OM-FIT record also exhibits abrupt events during the Holocene (e.g., the 8.2 kyr event), which are also reflected in the δ18O values of the calcite. These abrupt temperature changes during the last deglaciation and the Holocene correspond to variations seen in paleotemperature records across Europe and in Greenland ice cores. This clearly and quantitatively illustrates the influence of changes in the Atlantic Meridional Overturning Circulation, driven by subarctic freshening, on the climate of southern Europe.

Cold season temperatures in Europe have increased rapidly by about 1.2°C in the late 1980s, followed by relatively modest and regionally flat temperature trends thereafter. The abrupt change affected the entire European continent and coincided regionally with abrupt hydroclimatic changes such as a widespread reduction in snow days in Switzerland. However, the drivers and causes of the event are not well understood. Using a dynamical adjustment method based on statistical learning, we find that the continental-scale late 1980s abrupt winter warming and regional decreases in snow days can be attributed to cold conditions in the mid-1980s followed by a few exceptionally warm seasons. Both are caused by random atmospheric circulation variability superimposed upon a long-term and relatively homogenous warming trend, and do not require an external cause or change of the underlying dynamics of the system. This explanation is consistent with simulations from a 21-member regional climate model ensemble, in which four members display comparable abrupt temperature increases regionally driven by circulation and a long-term externally forced response. Overall, our analysis provides an observation-based interpretation of abrupt temperature change at the continental scale, associated hydroclimatic changes regionally, and its drivers. Furthermore, our method might contribute to improved mechanistic understanding of different observed climate phenomena in many regions of the world that experience high variability.

The mechanisms of abrupt seasonal temperature changes and warming (cooling) hiatuses remain unclear. Clarifying how they respond to various influencing factors is critically important to understanding their mechanisms. In this study, the influencing factors to which the abrupt changes in Tav, Tnav, and Txav were most sensitive followed the order of (AGG and CO2) > SR > WS > AMO > PDO > MEI > AO > AP > RH. Seasonal Tav had the greatest sensitivity to all influencing factors, followed by seasonal Tav and lastly by seasonal Txav. An abrupt temperature change occurred when AGG, AMO, or SR increased continuously to a certain value, when PDO was in a positive phase (warm phase) and increased continuously to a certain value, when MEI changed abruptly, when WS and RH continued to decline for a certain time and reached a certain tendency rate, or when AP continued to decline for a certain time and reached a certain value. During the period before and after the warming (cooling) hiatuses, the temperature at most of the stations only had a significant relationship with a few influencing factors, and the hiatuses in seasonal Tav, Tnav, and Txav were overall most sensitive to changes in WS, followed by changes in RH and lastly by changes in AP. The occurrence of warming (cooling) hiatuses was highly consistent with the variation trend of some influencing factors, which to some extent affected the warming (cooling) hiatuses. Abrupt seasonal temperature changes/warming (cooling) hiatuses are the combined effects of multiple influencing factors.

An abrupt temperature change and a warming hiatus have strongly influenced the global climate. This study focused on these changes in Inner Mongolia, China. This study used the central clustering method, Mann-Kendall mutation test and other methods to explore the abrupt temperature change and warming hiatus in three different temperature zones of the study region based on average annual data series. Among the temperature metrics investigated, average minimum temperature (Tnav) shifted the earliest, followed by average temperature (Tnv) and average maximum temperature (Txav). The latest change was observed in summer (1990s), whereas the earliest was observed in winter (1970s). Before and after the abrupt temperature change, Tnav fluctuated considerably, whereas there was only a slight change in Txav. Before and after the abrupt temperature change, the winter temperature changed more dramatically than the summer temperature. Before the abrupt temperature change, Tnav in the central region (0.322°C/10a) and west region (0.48°C/10a) contributed the most to the increasing temperatures. After the abrupt temperature change, Tnav in winter in the central region (0.519°C/10a) and in autumn in the west region (0.729°C/10a) contributed the most to the temperature increases. Overall, in the years in which temperature shifts occurred early, a warming hiatus also appeared early. The three temperature metrics in spring (1991) in the east region were the first to exhibit a warming hiatus. In the east region, Txav displayed the lowest rate of increase (0.412°C/a) in the period after the abrupt temperature change and before the warming hiatus, and the highest rate of increase after the warming hiatus.