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Greenland Ice Sheet Contribution to Future Global Sea Level Rise based on CmIP5 models

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Advances in Atmospheric Sciences 2014年第1期31卷 8-16页

作者： YAN Qing WANG Huijun ola m.johannessen ZHANG Zhongshi Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Nansen Environmental and Remote Sensing Center University of the Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Nansen Scientific Society Bjerknes Centre for Climate Research Uni Research

Sea level rise （SLR） is one of the major socioeconomic risks associated with global warming. mass losses from the Greenland ice sheet （GrIS） will be partially responsible for future SLR, although there are large uncertainties in modeled climate and ice sheet behavior. We used the ice sheet model SICOPOLIS （Simulation COde for POLythermal Ice Sheets） driven by climate projections from 20 models in the fifth phase of the Coupled model Intercomparison Project （CmIP5） to estimate the GrlS contribution to global SLR. Based on the outputs of the 20 models, it is estimated that the GrIS will contribute 0-16 （0-27） cm to global SLR by 2100 under the Representative Concentration Pathways （RCP） 4.5 （RCP 8.5） scenarios. The projected SLR increases further to 7-22 （7-33） cm with 2~basal sliding included. In response to the results of the multimodel ensemble mean, the ice sheet model projects a global SLR of 3 cm and 7 cm （10 cm and 13 cm with 2~basal sliding） under the RCP 4.5 and RCP 8.5 scenarios, respectively. In addition, our results suggest that the uncertainty in future sea level projection caused by the large spread in climate projections could be reduced with model-evaluation and the selective use of model outputs.

关键词： sea level rise Greenland ice sheet ice sheet modeling model evaluation

Population increase impacts the climate,using the sensitive Arctic as an example

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Atmospheric and Oceanic Science Letters 2022年第2期15卷 71-74页

作者： ola m.johannessen Elena V.Shalina Nansen Scientific Society BergenNorway Nansen International Environmental and Remote Sensing Centre St.PetersburgRussia Institute of Earth Sciences St.Petersburg State UniversityRussia

The global population during the last 100 years has increased from 2 to 7.7 billion,causing an increase in greenhouse gases in the *** order to see how population increase is directly related to physical variables of the climate,this Perspective article places observations and scenarios of climate change into context and puts forth a statistical modeling study on how the sensitive Arctic climate responds to the increasing *** relationships between population,Arctic sea-ice extent(SIE),and surface air temperature(SAT)are very strong,with the increasing population explaining 96%of the decreasing SIE and about 80%of the increasing SAT in the *** projection for the SIE using the population as a“proxy predictor”for a projected population of 10 billion people on the Earth in 2100,yields a SIE of 9.30 and 8.21 million km 2 for a linear and squared relationship,respectively,indicating no“tipping point”for the annual ice extent in this *** adds another dimension to climate understanding for the public at large using population as a proxy variable,instead of the more abstract CO_(2)*** also indicates that it is important to attempt to limit the ongoing increase in population,which is the main cause of the greenhouse gas emissions,in addition to reducing per capita emissions by an exponential increase in implementing renewable energy,a formidable challenge in this century.

关键词： Population Climate Sea ice Arctic

Will the summer sea ice in the Arctic reach a tipping point?

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 58-62页

作者： ola m.johannessen Elena V.Shalina Nansen Scientific Society BergenNorway Nansen International Environmental and Remote Sensing Centre St PetersburgRussia

The Arctic sea-ice cover has decreased in extent,area,and thickness over the last six *** global climate models project that the summer sea-ice extent(SIE)will decline to less than 1 million(mill.)km^(2) in this century,ranging from 2030 to the end of the century,indicating large ***,some models,using the same emission scenarios as required by the Paris Agreement to keep the global temperature below 2°C,indicate that the SIE could be about 2 ***^(2) in 2100 but with a large uncertainty of±1.5 ***^(2).Here,the authors take another approach by exploring the direct relationship between the SIE and atmospheric CO_(2) concentration for the summer-fall *** authors correlate the SIE and In(CO_(2)/CO_(2)r)during the period 1979-2022,where CO_(2)r is the reference value in *** these transient regression equations with an R2 between 0.78 and 0.87,the authors calculate the value that the CO_(2) concentration needs to reach for zero *** results are that,for July,the CO_(2) concentration needs to reach 691±16.5 ppm,for August 604±16.5 ppm,for September 563±17.5 ppm,and for October 620±21 *** values of CO_(2)for an ice-free Arctic are much higher than the targets of the Paris Agreement,which are 450 ppm in 2060 and 425 ppm in 2100,under the IPCC SSP1-2.6 *** these targets can be reached or even almost reached,the "no tipping point"hypothesis for the summer SIE may be valid.

关键词： Sea ice Arctic Climate change Tipping point

Accumulation over the Greenland Ice Sheet as Represented in Reanalysis Data

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Advances in Atmospheric Sciences 2011年第5期28卷 1030-1038页

作者：陈琳玲 ola m.johannessen 王会军 Atsumu OHmURA Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing 100029 mohn-Sverdrup Center Nansen Environmental and Remote Sensing Center Bergen 5006 Norway Nansen Scientific Society Bergen 5006 Norway mohn-Sverdrup Center Nansen Environmental and Remote Sensing CenterBergen 5006Norway Nansen Scientific Society Bergen 5006Norway Institute for Atmospheric and Climate Science Swiss Federal Institute of Technology(ETH)Zrich 8092Switzerland

Annual precipitation,evaporation,and calculated accumulation from reanalysis model outputs have been investigated for the Greenland Ice Sheet （GrIS）,based on the common period of *** ERA-40 and ERA-interim reanalysis data showed better agreement with observations than do NCEP-1 and NCEP-2 ***,ERA-interim showed the closest spatial distribution of accumulation to the *** temporal variations,ERA-interim showed the best correlation with precipitation observations at five synoptic stations,and the best correlation with in situ measurements of accumulation at nine ice core *** mean annual precipitation averaged over the whole GrIS from ERA-interim （363 mm yr 1） and mean annual accumulation （319 mm yr 1） are very close to the *** validation of accumulation calculated from reanalysis data against ice-core measurements suggests that further improvements to reanalysis models are needed.

关键词： Greenland Ice Sheet reanalysis data precipitation accumulation

Commemoration of the 15th Anniversary of Atmospheric and Oceanic Science Letters

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Atmospheric and Oceanic Science Letters 2022年第1期15卷 1-1页

作者： Huijun Wang ola m.johannessen Editors-in-Chief.

First published in late 2008 and currently in Volume 15(2022), Atmospheric and Oceanic Science Letters(AOSL) is now 15 years old. Looking back on the journey, hardships and happiness, difficulties and hope *** is an international journal for providing a rapid communication channel between academic communities concerned with the interdisciplinary research areas of atmospheric science, oceanography.

关键词： journal concerned providing

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Preface

Atmospheric and Oceanic Science Letters 2018年第2期11卷 103-103页

作者： Hui-Jun Wang ola m.johannessen Atmospheric and Oceanic Science Letters

First published in late 2008 and currently in Volume 11 （2018）,Atmospheric and Oceanic Science Letters （AOSL） is unique in providing a rapid communication channel between academic communities concerned with the interdisciplinary research areas of atmospheric science and physical *** approach allows the journal to cover such critical issues as climate change,the cryosphere,water resources,wind energy,drought and flood,and smog,amongst many *** is co-sponsored by the Institute of Atmospheric Physics （IAP） and the Chinese meteorological Society （CmS）,and it is now jointly published by the Taylor ＆ Francis Group （since 2016） and Science Press.

关键词：大气海洋科学

Decreasing Arctic Sea Ice mirrors Increasing CO_2 on Decadal Time Scale

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Atmospheric and Oceanic Science Letters 2008年第1期1卷 51-56页

作者： ola m.johannessen mohn-Sverdrup Center for Global Ocean Studies and Operational Oceanography / Nansen Environmental and Remote Sensing Center Geophysical Institute University of Bergen

Arctic sea ice is a keystone indicator of greenhouse-gas induced global climate change, which is expected to be amplified in the Arctic. Here we directly compare observed variations in arctic sea-ice extent and CO 2 since the beginning of the 20th century, identifying a strengthening linkage, such that in recent decades the rate of sea-ice decrease mirrors the increase in CO 2 , with r ～ -0.95 over the last four decades, thereby indicating that 90% (r 2 ～ 0.90) of the decreasing sea-ice extent is empirically "accounted for" by the increasing CO 2 in the atmosphere. The author presents an empirical relation between annual sea-ice extent and global atmospheric CO 2 concentrations, in which sea-ice reductions are linearly, inversely proportional to the magnitude of increase of CO 2 over the last few decades. This approximates sea-ice changes during the most recent four decades, with a proportionality constant of 0.030 million km 2 per ppmv CO 2 . When applied to future emission scenarios of the Intergovernmental Panel on Climate Change (IPCC), this relationship results in substantially faster ice decreases up to 2050 than predicted by IPCC models. However, departures from this projection may arise from non-linear feedback effects and/or temporary natural variations on interannual timescales, such as the record minimum of sea-ice extent observed in September 2007.

关键词： CO2 increase ice decrease ice projection to2050

Climate change in the North- past, present and future

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Episodes 2008年第1期31卷 163-167页

作者： Joern Thiede ola m. johannessen Alfred-Wegner-Institute for Polar and marine Research in the Helmholtz-Association Am Handelshafen 12 D-27570 Bremerhaven Germany. Nansen Environmental and Remote Sensing Centre （NERSC） Geophysical Institute University of Bergen Thormoehlensgate 47 N-5006 Bergen Norway.

The Nordic countries have produced famous polar explorers and researchers who have generated climate research schools at a variety of locations. The dependence of these countries with respect to the lifelihood of their societies, of their use of lands and seas, the exploitation of marine living and non-living resources have made climate research an eminent topic, and many outstanding discoveries of longand short-term climate change have been made for the first time in Scandinavia. These include early contributions to our understanding of the geological effects of continent-wide glaciations during the ice ages, the complex postglacial history of the Baltic Sea and the varved sediment sequences preserved from lakes with an extraordinary seasonality in their sediment input, as well as the detailed records of temperature, ice texture and impurities and greenhouse gas variations of the last Glacial and of the Holocene preserved in the ice cores from Greenland. Iceland with its volcanic sequences and intercalated sediment layers not only preserved the history of this subaerial segment of the mid-Atlantic Ridge, but also easily datable paleoclimate records. The fate of the Vikings, who settled during the medieval climate optimum on Iceland and later on Greenland and who lost their habitat on Greenland at the beginning of the Little Ice Age, illustrates vividly the climate-dependent subsistence of the indigenous and non-indigenous Scandinavian populations. modern Scandinavian climate research institutions also include sophisticated modelling groups.

关键词：气候变化北方地区生存条件地质特征

Climate Change in the Subtropical Jetstream during 1950–2009

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Advances in Atmospheric Sciences 2015年第1期32卷 140-148页

作者： B.ABISH P.V.JOSEPH ola.m.johannessen Nansen Environmental Research Centre India Department of Atmospheric Sciences Cochin University of Science and Technology Nansen Environmental and Remote Sensing Center Nansen Scientific Society

A study of six decades（1950–2009） of reanalysis data reveals that the subtropical jetstream（STJ） of the Southern（Northern） Hemisphere between longitudes 0°E and 180°E has weakened（strengthened） during both the boreal winter（January,February） and summer（July, August） seasons. The temperature of the upper troposphere of the midlatitudes has a warming trend in the Southern Hemisphere and a cooling trend in the Northern Hemisphere. Correspondingly, the north–south temperature gradient in the upper troposphere has a decreasing trend in the Southern Hemisphere and an increasing trend in the Northern Hemisphere, which affects the strength of the STJ through the thermal wind relation. We devised a method of isotach analysis in intervals of 0.1 m s-1in vertical sections of hemispheric mean winds to study the climate change in the STJ core wind speed, and also core height and latitude. We found that the upper tropospheric cooling of the Asian mid-latitudes has a role in the strengthening of the STJ over Asia, while throughout the rest of the globe the upper troposphere has a warming trend that weakens the STJ. Available studies show that the mid-latitude cooling of the upper troposphere over Asia is caused by anthropogenic aerosols（particularly sulphate aerosols） and the warming over the rest of the global mid-latitude upper troposphere is due to increased greenhouse gases in the atmosphere.

关键词： subtropical jetstream upper troposphere greenhouse gases aerosols