Geografiska Annaler Series A-Physical Geography最新文献_第9页

Recent climate-induced shape changes of the ice summit of Kebnekaise, Northern Sweden 最近气候引起的瑞典北部Kebnekaise冰顶的形状变化

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-11-19 DOI: 10.1080/04353676.2018.1542130

P. Holmlund, E. S. Holmlund

{"title":"Recent climate-induced shape changes of the ice summit of Kebnekaise, Northern Sweden","authors":"P. Holmlund, E. S. Holmlund","doi":"10.1080/04353676.2018.1542130","DOIUrl":"https://doi.org/10.1080/04353676.2018.1542130","url":null,"abstract":"ABSTRACT The ice summit of Kebnekaise is slowly melting down as a consequence of climate change. In August 2018 this peak, which for a long time has been the highest in Sweden, reached an elevation a few decimetres lower than the nearby situated northern summit in solid rock. It has become a symbol of the fragility of nature. Its areal extent and shape have varied over time and its height has ranged within approximately 15 m during the twentieth century. Since the turn of the century, the ice summit has decreased to a new lower and smaller level but the changes are not uniform, and they show a complex relation between weather parameters and the shape and size of the summit. Layers in the ice include climate information of past changes. But what changes are we able to determine by examining gradually exposed dust layers, or by coring the summit. In this paper, we are analysing the late changes in shape and volume of the ice summit and we place the results into a paleo climate discussion. We have used photogrammetric methods to map the geometry of the summit at different dates when data has been available. We have also done a multiple regression to analyse the relation between the summit elevation and the net mass balance of the nearby located Storglaciären. The correlation is good from mid 1970s until now but weak prior to that. It is herein explained by former uncertainties of the geographic position of the summit.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"152 1","pages":"68 - 78"},"PeriodicalIF":1.5,"publicationDate":"2018-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78600260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A comparison of modelled ice thickness and volume across the entire Antarctic Peninsula region 整个南极半岛地区模拟冰的厚度和体积的比较

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-10-31 DOI: 10.1080/04353676.2018.1539830

J. Carrivick, B. Davies, W. James, M. McMillan, N. Glasser

{"title":"A comparison of modelled ice thickness and volume across the entire Antarctic Peninsula region","authors":"J. Carrivick, B. Davies, W. James, M. McMillan, N. Glasser","doi":"10.1080/04353676.2018.1539830","DOIUrl":"https://doi.org/10.1080/04353676.2018.1539830","url":null,"abstract":"ABSTRACT Understanding Antarctic Peninsula glacier evolution requires distributed ice thickness and subglacial topography. To date, 80% of the Antarctic Peninsula mainland ice volume has only been determined at low-resolution (1 km post spacing) and the distributed ice thickness of glaciers on surrounding islands has never been quantified. In this study we applied a perfect plasticity model, selected for its simplicity, low data requirements and minimal parameterisation, to estimate glacier thickness, subglacial topography and ice volume for the entire Antarctic Peninsula region. We compared the output of this simple model to that of a more sophisticated but spatially-restricted model and also to the spatially-coarse but more extensive Bedmap2 dataset. The simple model produced mean differences of 1.4 m (std. dev. 243 m) in comparison with the more sophisticated approach for the mountainous parts of the Peninsula. It produced similar volumes for tidewater glaciers but gave unrealistic ice thickness around grounding lines. Ice thickness across low gradient plateau surfaces are mis-represented by a perfect plasticity model and thus for the southern part of the Peninsula only regional ice volume can be approximated by our model. Overall, with consideration of ice situated below sea level, model results suggest that Trinity Peninsula, Graham Land, the part of Palmer Land north of 74°S and all glaciers on islands contain an ice mass of ∼200 300 Gt, with sea level equivalent of 553 mm (± 11.6 mm). Of this total 8% is from glaciers on islands, 70% of which is from Alexander Island.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"35 1","pages":"45 - 67"},"PeriodicalIF":1.5,"publicationDate":"2018-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79394350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Unravelling the recent dynamics of headwaters based on a combined dendrogeomorphic approach (a case study from the Sudetes Mts., Czech Republic) 基于树木地貌组合方法揭示水源近期动态变化(以捷克苏台德山脉为例)

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-10-27 DOI: 10.1080/04353676.2018.1539333

R. Tichavský

{"title":"Unravelling the recent dynamics of headwaters based on a combined dendrogeomorphic approach (a case study from the Sudetes Mts., Czech Republic)","authors":"R. Tichavský","doi":"10.1080/04353676.2018.1539333","DOIUrl":"https://doi.org/10.1080/04353676.2018.1539333","url":null,"abstract":"ABSTRACT Headwater catchments are frequently prone to debris flows/floods. Dendrogeomorphic methods allow for the accurate dating of the frequencies and spatial patterns of these events. Nevertheless, a combined approach based on the sampling of increment cores from tree stems and the extraction of cross-sections of scarred roots has been rarely used together at one site to determine the headwater dynamics. Such sampling strategy was performed in the Rudohorský potok catchment (the Hrubý Jeseník Mountains, Eastern Sudetes, Czech Republic) to compile the debris flow/flood chronology and to describe the detailed spatial patterns in the studied sub-catchments. In total, 44 events of increased hydrogeomorphic activity during the last 110 years were identified based on the analysis of 860 growth disturbances from 322 trees and 85 roots. The largest events (debris flows) occurred in 1921, 1951, 1965, 1975, 1991, 1997, 2001 and 2010. Higher dynamics of hydrogeomorphic processes were investigated in the sub-catchment affected by deep-seated rockslides. The inclusion of root analyses facilitated the completion of the event chronology mainly during the last 20 years. With respect to the decreasing sensitivity of tree stems with increasing age to the recording of geomorphic disturbances, the root analysis helped to better illustrate the spatial imprint of recent debris flow events (especially the most recent one in 2010).","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"53 1","pages":"16 - 33"},"PeriodicalIF":1.5,"publicationDate":"2018-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87383445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Rock glaciers in central Patagonia 巴塔哥尼亚中部的岩石冰川

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-10-22 DOI: 10.1080/04353676.2018.1525683

H. Selley, S. Harrison, N. Glasser, Olaf Wündrich, D. Colson, A. Hubbard

引用次数: 10

Thanks 谢谢

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-10-02 DOI: 10.1080/04353676.2018.1533161

Weidong Zhang

引用次数: 0

Revisiting glaciological measurements on Haupapa/Tasman Glacier, New Zealand, in a contemporary context 在当代背景下重新审视新西兰Haupapa/Tasman冰川的冰川学测量

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-10-02 DOI: 10.1080/04353676.2018.1522958

H. Purdie, B. Anderson, A. Mackintosh, W. Lawson

{"title":"Revisiting glaciological measurements on Haupapa/Tasman Glacier, New Zealand, in a contemporary context","authors":"H. Purdie, B. Anderson, A. Mackintosh, W. Lawson","doi":"10.1080/04353676.2018.1522958","DOIUrl":"https://doi.org/10.1080/04353676.2018.1522958","url":null,"abstract":"ABSTRACT Compilation of fragmented glaciological data, spanning more than a century at Haupapa/Tasman Glacier, provides new insight on how this glacier is changing over time. Despite consistency in high accumulation on the glacier, dramatic surface thinning and up-glacier expansion of supraglacial debris highlights that the glacier is currently in disequilibrium with climate. However, pauses in the rate of debris emergence indicate that despite ongoing terminus retreat at the proglacial lake, a subtle response to climate is still detectable mid-glacier. Analysis of surface velocity data at key locations reveals no trend over time at the Malte Brun site in the upper ablation area, but recent deceleration was recorded near the Ball Glacier confluence, located 5 km up-glacier from the current terminus. Near-terminus acceleration during a period of rapid lake expansion, followed by more recent deceleration, demonstrates that at this time, ice thinning at Haupapa/Tasman Glacier is likely being driven by negative surface mass balance as opposed to dynamic thinning associated with proglacial lake enlargement.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"17 1","pages":"351 - 369"},"PeriodicalIF":1.5,"publicationDate":"2018-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82543413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

The impact of geothermal heat flux on the last Scandinavian ice sheet over W Poland and E Germany 地热通量对波兰西部和德国东部最后斯堪的纳维亚冰盖的影响

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-09-25 DOI: 10.1080/04353676.2018.1524711

Izabela Szuman, Jakub Kalita, M. Ewertowski

{"title":"The impact of geothermal heat flux on the last Scandinavian ice sheet over W Poland and E Germany","authors":"Izabela Szuman, Jakub Kalita, M. Ewertowski","doi":"10.1080/04353676.2018.1524711","DOIUrl":"https://doi.org/10.1080/04353676.2018.1524711","url":null,"abstract":"ABSTRACT Geothermal heat flux (GHF) is heat supplied to the base of the ice sheet. It plays an important role in controlling ice sheet stability and affects basal temperatures, melting, and ice flow velocities. Here, we presume that the high GHF, as high as c. 110 mW m−2 over W Poland and more than 90 mW m−2 over E Germany, might have been one of the factors influencing the last Scandinavian ice sheet behaviour. For the analysed case, a GHF of 80 mW m−2 is more or less at the level of upward heat conduction. The difference in basal temperatures between areas with higher and lower GHF due to ice insulation was about 3–4oC. The minimum heat flow needed to reach the pressure melting point for the SIS beneath the ice streams in central west Poland was about 60 mW m−2. Possible interpretations would be that any excesses of heat participated in the meltwater production (by over 8 mm) that was at least partly stored subglacially due to the low-permeable bed and lack of channelised drainage traces, and maintained a fast ice streaming or enable reaching the pressure melting point or higher temperatures could counteract the freezing present near the ice sheet margin. The fast ice flow over central west Poland is confirmed by sedimentary and geomorphological evidence (e.g. mega-scale glacial lineations).","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"39 1","pages":"388 - 403"},"PeriodicalIF":1.5,"publicationDate":"2018-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80595047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Natural conditions of coarse bedload transport in headwater catchments (Western Tatras, Poland) 水源集水区粗质河床输运的自然条件(西塔特拉，波兰)

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-09-19 DOI: 10.1080/04353676.2018.1522957

E. Płaczkowska, K. Krzemień

{"title":"Natural conditions of coarse bedload transport in headwater catchments (Western Tatras, Poland)","authors":"E. Płaczkowska, K. Krzemień","doi":"10.1080/04353676.2018.1522957","DOIUrl":"https://doi.org/10.1080/04353676.2018.1522957","url":null,"abstract":"ABSTRACT The aim of the study was to examine the magnitude and frequency of bedload transport in 1st–3rd order headwater catchments (with an area <2 km2) in the Western Tatras. The study was carried out in 19 headwater catchments, divided into two groups: (1) alpine catchments, and (2) montane catchments. Bedload transport measurements were carried out at intervals over a period of 40 years using the painted stone method. During large floods observed in the main stream (Q > 5 m3 s−1), usually associated with prolonged rainfall or a combination of both snowmelt and rainfall, it can be expected that bedload will also be activated in its tributaries and headwater sections. Bedload transport may also occur during snowmelts, but this type of flood is of a completely local nature. During small local floods, the role of the local channel structure is quite important. Channel topography can slow down transported bedload, which is particularly visible within alluvial fans. During high-energy events, this effect disappears, and the distance of bedload transport increases downstream. In alpine channels, bedload transport occurs on a much smaller scale than is the case in montane channels and it occurs along the entire channel length. The distance of bedload transport, its size, and the frequency of occurrence of geomorphologically-active floods are smaller in alpine catchments than in montane ones. In alpine channels, the maximum distance of bedload transport was 18.2 m, and in montane channels, distances reached 165 m.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"119 1","pages":"370 - 387"},"PeriodicalIF":1.5,"publicationDate":"2018-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87116149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Impacts of changes in climate and land cover-land use on flood characteristics in Gorganrood Watershed (Northeastern Iran) during recent decades* 近几十年来气候和土地利用变化对伊朗东北部Gorganrood流域洪水特征的影响*

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-09-09 DOI: 10.1080/04353676.2018.1515578

M. Irannezhad, M. Minaei, S. Ahmadian, Deliang Chen

{"title":"Impacts of changes in climate and land cover-land use on flood characteristics in Gorganrood Watershed (Northeastern Iran) during recent decades*","authors":"M. Irannezhad, M. Minaei, S. Ahmadian, Deliang Chen","doi":"10.1080/04353676.2018.1515578","DOIUrl":"https://doi.org/10.1080/04353676.2018.1515578","url":null,"abstract":"ABSTRACT This study evaluated the effects of changes in climate and land cover-land use (LCLU) on flood intensity and frequency in the Gorganrood Watershed (GW) located in the northeast of Iran during recent decades. For this purpose, hydroclimatic (precipitation, temperature, and river discharge) time series recorded at nine stations placed in the GW during 1973–2014 were used. Flood characteristics in terms of mean, maximum and number of peaks at five discharge stations (Galikash, Gonbad, Huji Ghushan, Tamar, and Tangrah) sited in the outlet of GW sub-basins were determined applying the Peak-Over-Threshold (POT) method to daily specific discharges. This is designed to remove the effect of the different size of sub-basins. The whole study period was divided into three 14-years segments (1973–1986, 1987–2000 and 2001–2014) based on satellite LCLU maps produced for 1973, 1986, 2000 and 2014. In the GW and its sub-basins during recent decades, both flood intensity and frequency increased, the climate became wetter and warmer, and LCLU mostly converted from rangeland to farmland. The partial correlation analyses identified that flood frequency in GW was primarily connected to the LCLU conversions, but moderately to observed wetter and warmer climate. Similarly, the Tamar sub-basin experienced effects of LCLU and climate on the maximum and the number of peaks. In Haji Ghushan, wetter and warmer climate resulted in more intense and frequent floods. Increases in precipitation appear to have played the most important role in the higher flood frequency in Galikash.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"27 1","pages":"340 - 350"},"PeriodicalIF":1.5,"publicationDate":"2018-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79663154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Global and regional climate responses to national-committed emission reductions under the Paris agreement 根据《巴黎协定》对各国承诺的减排作出全球和区域气候反应

IF 1.5 4区地球科学

Geografiska Annaler Series A-Physical Geography Pub Date : 2018-07-03 DOI: 10.1080/04353676.2018.1488538

Fang Wang, Q. Ge, Deliang Chen, J. Luterbacher, K. Tokarska, Z. Hao

{"title":"Global and regional climate responses to national-committed emission reductions under the Paris agreement","authors":"Fang Wang, Q. Ge, Deliang Chen, J. Luterbacher, K. Tokarska, Z. Hao","doi":"10.1080/04353676.2018.1488538","DOIUrl":"https://doi.org/10.1080/04353676.2018.1488538","url":null,"abstract":"ABSTRACT To stabilize global mean temperature change within the range of 1.5–2.0°C in accordance with the Paris Agreement, countries worldwide submitted their Intended Nationally Determined Contributions with their proposed emission reductions. However, it remains unclear what the resulting climate change in terms of temperature and precipitation would be in response to the Intended Nationally Determined Contribution emission efforts. This study quantifies the global and regional temperature and precipitation changes in response to the updated Intended Nationally Determined Contribution scenarios, using simulations of 14 Fifth Coupled Climate Model Intercomparison Project models. Our results show that Intended Nationally Determined Contribution emissions would lead to a global mean warming of 1.4°C (1.3–1.7°C) in 2030 and 3.2°C (2.6–4.3°C) in 2100, above the preindustrial level (the 1850–1900 average). Spatially, the Arctic is projected to have the largest warming, 2.5 and 3 times the global average for 2030 and 2100, respectively, with strongest positive trends at 70–85°N over Asia, Europe and North America (6.5–9.0°C). The excessive warming under Intended Nationally Determined Contribution scenarios is substantially above the 1.5°C or 2.0°C long-term stabilization level. Global mean precipitation is projected to be similar to preindustrial levels in 2030, and an increase of 6% (4–9%) by 2100 compared with the preindustrial level. Regional precipitation changes will be heterogeneous, with significant increases over the equatorial Pacific (about +120%) and strong decreases over the Mediterranean, North Africa and Central America (−15% – −30%). These results clearly show that it is necessary to adjust and strengthen national mitigation efforts on current Intended Nationally Determined Contributions to meet the long-term temperature target.","PeriodicalId":55112,"journal":{"name":"Geografiska Annaler Series A-Physical Geography","volume":"70 1","pages":"240 - 253"},"PeriodicalIF":1.5,"publicationDate":"2018-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77923260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13