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1. Vegetation type is an important predictor of the arctic summer land surface energy budget

Author

Oehri, Jacqueline, Schaepman-Strub, Gabriela, Kim, Jin-Soo, Grysko, Raleigh, Kropp, Heather, Grünberg, Inge, Zemlianskii, Vitalii, Sonnentag, Oliver, Euskirchen, Eugénie S., Reji Chacko, Merin, Muscari, Giovanni, Blanken, Peter D., Dean, Joshua F., di Sarra, Alcide, Harding, Richard J., Sobota, Ireneusz, Kutzbach, Lars, Plekhanova, Elena, Riihelä, Aku, Boike, Julia, Miller, Nathaniel B., Beringer, Jason, López-Blanco, Efrén, Stoy, Paul C., Sullivan, Ryan C., Kejna, Marek, Parmentier, Frans-Jan W., Gamon, John A., Mastepanov, Mikhail, Wille, Christian, Jackowicz-Korczynski, Marcin, Karger, Dirk N., Quinton, William L., Putkonen, Jaakko, van As, Dirk, Christensen, Torben R., Hakuba, Maria Z., Stone, Robert S., Metzger, Stefan, Vandecrux, Baptiste, Frost, Gerald V., Wild, Martin, Hansen, Birger, Meloni, Daniela, Domine, Florent, te Beest, Mariska, Sachs, Torsten, Kalhori, Aram, Rocha, Adrian V., Williamson, Scott N., Morris, Sara, Atchley, Adam L., Essery, Richard, Runkle, Benjamin R. K., Holl, David, Riihimaki, Laura D., Iwata, Hiroki, Schuur, Edward A. G., Cox, Christopher J., Grachev, Andrey A., McFadden, Joseph P., Fausto, Robert S., Göckede, Mathias, Ueyama, Masahito, Pirk, Norbert, de Boer, Gijs, Bret-Harte, M. Syndonia, Leppäranta, Matti, Steffen, Konrad, Friborg, Thomas, Ohmura, Atsumu, Edgar, Colin W., Olofsson, Johan, and Chambers, Scott D.

Published
2022
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2. Contributors

Author

Allison, Ian, primary, Alzate, Bernardo Pulgarín, additional, Amann, Florian, additional, Arenson (U.), Lukas, additional, Bartelt, Perry, additional, Bebiolka, Anke, additional, Bodin, Xavier, additional, Bolch, Tobias, additional, Brandefelt, Jenny, additional, Bründl, Michael, additional, Cáceres Correa, Bolívar E., additional, Callaghan, Terry V., additional, Carey, Mark, additional, Christiansen, Hanne H., additional, Clague, John J., additional, Cohen, Denis, additional, Colgan, William, additional, Cook, Simon, additional, Craw Burns, Patty A., additional, Delaloye, Reynald, additional, Delaney, Keith B., additional, Deline, Philip, additional, Espizua, Lydia, additional, Evans, Stephen G., additional, Ewen, Tracy, additional, Failletaz, Jérôme, additional, Fischer, Luzia, additional, Fischer, Urs H., additional, Fowler, Captain David, additional, Gärtner-Roer, Isabelle, additional, Geertsema, Marten, additional, Giardino, Marco, additional, Gilbert, Adrien, additional, Granados, Hugo Delgado, additional, Gruber, Stephan, additional, Haeberli, Wilfried, additional, Harper, Joel, additional, Harrison, Will D., additional, Hasler, Andreas, additional, Heckmann, Tobias, additional, Hirschorn, Sarah, additional, Huggel, Christian, additional, Huss, Matthias, additional, Jenicek, Michal, additional, Jensen, Mark, additional, Johansson, Margareta, additional, Kääb, Andreas, additional, Kennell, Laura, additional, King, Matt, additional, Kirkbride, Martin, additional, Korup, Oliver, additional, Krautblatter, Michael, additional, Kubat, Ivana, additional, Lai, Alexandre W., additional, Liakka, Johan, additional, Magnin, Florence, additional, Margreth, Stefan, additional, Marshall, Becca, additional, Marshall, Hans Peter, additional, McColl, Samuel, additional, McDowell, Graham, additional, Miranda, Patricia Julio, additional, Moore, Jeffrey, additional, Mothes, Patricia, additional, Moulton, Holly, additional, Näslund, Jens-Ove, additional, Normani, Stefano, additional, Nosenko, Gennady A., additional, Núñez, Gerardo Carrasco, additional, O’Connor, Jim E., additional, Ohmura, Atsumu, additional, Osipova, Galina B., additional, Paul, Frank, additional, Portocarrero, César, additional, Provant, Zachary, additional, Ramos, Jorge Cortés, additional, Rana, Nahyan M., additional, Ravanel, Ludovic, additional, Reynolds, John M., additional, Roa, Hugo Moreno, additional, Sayed, Mohamed, additional, Schoeneich, Philippe, additional, Schweizer, Jürg, additional, Seibert, Jan, additional, Streletskiy, Dmitry, additional, Stück, Heidrun, additional, Swift, Darrel A., additional, Truffer, Martin, additional, van Herwijnen, Alec, additional, Vicuña, Luis, additional, Vieli, Andreas, additional, Viviroli, Daniel, additional, Weber, Samuel, additional, Weitkamp, Axel, additional, and Whiteman, Colin, additional

Published
2021
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5. New eyes in the sky measure glaciers and ice sheets

Author

Kieffer, Hugh, Kargel, Jeffrey S, Barry, Roger, Bindschadler, Robert, Bishop, Michael, MacKinnon, David, Ohmura, Atsumu, Raup, Bruce, Antoninetti, Massimo, Bamber, Jonathan, Braun, Matthias, Brown, Ian, Cohen, Denis, Copland, Luke, DueHagen, Jon, Engeset, Rune V, Fitzharris, Blair, Fujita, Koji, Haeberli, Wilfried, Hagen, Jon Oue, Hall, Dorothy, Hoelzle, Martin, Johansson, Maria, Kaab, Andi, Koenig, Max, Konovalov, Vladimir, Maisch, Max, Paul, Frank, Rau, Frank, Reeh, Niels, Rignot, Eric, Rivera, Andres, de Wildt, Martiyn De Ruyter, Scambos, Ted, Schaper, Jesko, Scharfen, Greg, Shroder, Jack, Solomina, Olga, Thompson, David, Veen, Kees, Wohlleben, Trudy, and Young, Neal

Subjects
Affordable and Clean Energy, Climate Action, Meteorology & Atmospheric Sciences
Published
2000

6. Rising solar and thermal greenhouse radiation drive rapid warming over the continents

Author

Philipona, Rolf, Marty, Christoph, Duerr, Bruno, and Ohmura, Atsumu

Subjects
solar radiation thermal greenhouse radiation, radiation measurements, rapidly increasing warming over continents
Abstract

Rising anthropogenic greenhouse gases, such as CO2, CH4, N2O and others, are known to absorb and emit terrestrial thermal radiation back to the Earth's surface, leading to radiative forcing and rising surface temperatures. Nonetheless, radiation measurements now show that the rapid increase in temperature over continents since the end of the last century, which is more than twice as large as the average global warming, is also related to a clearing of the sky over land surfaces, which leads to an increase in sunshine hours, and hence, increasing solar radiation absorbed at the Earth's surface. By contrasting rising temperatures with annual sunshine hours and solar and thermal radiation in Central Europe, the measurements show that thermal radiation steadily increases owing to the rising greenhouse effect. However, the rapidly increasing warming since the end of the last century has been reinforced by a strong increase in solar radiation, resulting from rising annual sunshine hours as a positive greenhouse warming feedback, which is larger than the increase in thermal greenhouse radiation, and hence, the strongest driver of the rapidly increasing warming over continents. The rapid temperature increase in Central Europe, of more than one degree over the last decade, is larger in lowlands than in the Alps., Meteorologische Zeitschrift, 32 (1), ISSN:0941-2948, ISSN:1610-1227

Published
2023
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8. Vegetation type is an important predictor of the arctic summer land surface energy budget

Author

Environmental Sciences, Afd Marine and Atmospheric Research, Spatial Ecology and Global Change, Sub Algemeen Marine & Atmospheric Res, Oehri, Jacqueline, Schaepman-Strub, Gabriela, Kim, Jin-Soo, Grysko, Raleigh, Kropp, Heather, Grünberg, Inge, Zemlianskii, Vitalii, Sonnentag, Oliver, Euskirchen, Eugénie S., Reji Chacko, Merin, Muscari, Giovanni, Blanken, Peter D., Dean, Joshua F., di Sarra, Alcide, Harding, Richard J., Sobota, Ireneusz, Kutzbach, Lars, Plekhanova, Elena, Riihelä, Aku, Boike, Julia, Miller, Nathaniel B., Beringer, Jason, López-Blanco, Efrén, Stoy, Paul C., Sullivan, Ryan C., Kejna, Marek, Parmentier, Frans-Jan W., Gamon, John A., Mastepanov, Mikhail, Wille, Christian, Jackowicz-Korczynski, Marcin, Karger, Dirk N., Quinton, William L., Putkonen, Jaakko, van As, Dirk, Christensen, Torben R., Hakuba, Maria Z., Stone, Robert S., Metzger, Stefan, Vandecrux, Baptiste, Frost, Gerald V., Wild, Martin, Hansen, Birger, Meloni, Daniela, Domine, Florent, te Beest, Mariska, Sachs, Torsten, Kalhori, Aram, Rocha, Adrian V., Williamson, Scott N., Morris, Sara, Atchley, Adam L., Essery, Richard, Runkle, Benjamin R. K., Holl, David, Riihimaki, Laura D., Iwata, Hiroki, Schuur, Edward A. G., Cox, Christopher J., Grachev, Andrey A., McFadden, Joseph P., Fausto, Robert S., Göckede, Mathias, Ueyama, Masahito, Pirk, Norbert, de Boer, Gijs, Bret-Harte, M. Syndonia, Leppäranta, Matti, Steffen, Konrad, Friborg, Thomas, Ohmura, Atsumu, Edgar, Colin W., Olofsson, Johan, Chambers, Scott D., Environmental Sciences, Afd Marine and Atmospheric Research, Spatial Ecology and Global Change, Sub Algemeen Marine & Atmospheric Res, Oehri, Jacqueline, Schaepman-Strub, Gabriela, Kim, Jin-Soo, Grysko, Raleigh, Kropp, Heather, Grünberg, Inge, Zemlianskii, Vitalii, Sonnentag, Oliver, Euskirchen, Eugénie S., Reji Chacko, Merin, Muscari, Giovanni, Blanken, Peter D., Dean, Joshua F., di Sarra, Alcide, Harding, Richard J., Sobota, Ireneusz, Kutzbach, Lars, Plekhanova, Elena, Riihelä, Aku, Boike, Julia, Miller, Nathaniel B., Beringer, Jason, López-Blanco, Efrén, Stoy, Paul C., Sullivan, Ryan C., Kejna, Marek, Parmentier, Frans-Jan W., Gamon, John A., Mastepanov, Mikhail, Wille, Christian, Jackowicz-Korczynski, Marcin, Karger, Dirk N., Quinton, William L., Putkonen, Jaakko, van As, Dirk, Christensen, Torben R., Hakuba, Maria Z., Stone, Robert S., Metzger, Stefan, Vandecrux, Baptiste, Frost, Gerald V., Wild, Martin, Hansen, Birger, Meloni, Daniela, Domine, Florent, te Beest, Mariska, Sachs, Torsten, Kalhori, Aram, Rocha, Adrian V., Williamson, Scott N., Morris, Sara, Atchley, Adam L., Essery, Richard, Runkle, Benjamin R. K., Holl, David, Riihimaki, Laura D., Iwata, Hiroki, Schuur, Edward A. G., Cox, Christopher J., Grachev, Andrey A., McFadden, Joseph P., Fausto, Robert S., Göckede, Mathias, Ueyama, Masahito, Pirk, Norbert, de Boer, Gijs, Bret-Harte, M. Syndonia, Leppäranta, Matti, Steffen, Konrad, Friborg, Thomas, Ohmura, Atsumu, Edgar, Colin W., Olofsson, Johan, and Chambers, Scott D.

Published
2022

11. Contributors

Author

Allison, Ian, primary, Alzate, Bernardo Pulgarín, additional, Anisimov, Oleg, additional, Arenson, Lukas U., additional, Bartelt, Perry, additional, Bebiolka, Anke, additional, Bolch, Tobias, additional, Brandefelt, Jenny, additional, Bründl, Michael, additional, Cáceres Correa, Bolívar E., additional, Callaghan, Terry V., additional, Carey, Mark, additional, Christiansen, Hanne H., additional, Clague, John J., additional, Colgan, William, additional, Cook, Simon, additional, Craw Burns, Patty A., additional, Delaloye, Reynald, additional, Delaney, Keith B., additional, Deline, Philip, additional, Espizua, Lydia, additional, Evans, Stephen G., additional, Ewen, Tracy, additional, Fischer, Urs H., additional, Fischer, Luzia, additional, Follin, Sven, additional, Fowler, Captain David, additional, Gärtner-Roer, Isabelle, additional, Geertsema, Marten, additional, Giardino, Marco, additional, Granados, Hugo Delgado, additional, Gruber, Stephan, additional, Haeberli, Wilfried, additional, Harrison, William D., additional, Hasler, Andreas, additional, Heckmann, Tobias, additional, Hirschorn, Sarah, additional, Huggel, Christian, additional, Huss, Matthias, additional, Jackson, Jerrilynn, additional, Jenicek, Michal, additional, Jensen, Mark, additional, Johansson, Margareta, additional, Kääb, Andreas, additional, Keller, Siegfried, additional, Kennell, Laura, additional, King, Matt, additional, Kirkbride, Martin, additional, Korup, Oliver, additional, Krautblatter, Michael, additional, Kubat, Ivana, additional, Lai, Alexandre W., additional, Magnin, Florence, additional, Margreth, Stefan, additional, Marshall, Hans Peter, additional, McColl, Samuel, additional, McDowell, Graham, additional, Miranda, Patricia Julio, additional, Moore, Jeffrey, additional, Mothes, Patricia, additional, Näslund, Jens-Ove, additional, Normani, Stefano, additional, Nosenko, Gennady A., additional, Núñez, Gerardo Carrasco, additional, O'Connor, Jim E., additional, Ohmura, Atsumu, additional, Osipova, Galina B., additional, Paul, Frank, additional, Portocarrero, César, additional, Ramos, Jorge Cortés, additional, Ravanel, Ludovic, additional, Reynolds, John M., additional, Roa, Hugo Moreno, additional, Sayed, Mohamed, additional, Schoeneich, Philippe, additional, Schweizer, Jürg, additional, Seibert, Jan, additional, Selroos, Jan-Olof, additional, Streletskiy, Dmitry, additional, Swift, Darrel A., additional, Truffer, Martin, additional, van Herwijnen, Alec, additional, Vasiliev, Alexander, additional, Vicuña, Luis, additional, Vidstrand, Patrik, additional, Vieli, Andreas, additional, and Whiteman, Colin, additional

Published
2015
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23. Data quality assessment and the long-term trend of ground solar radiation in China

Author

Shi, Guang-Yu, Hayasaka, Tadahiro, Ohmura, Atsumu, Chen, Zhi-Hua, Wang, Biao, Zhao, Jian-Qi, Che, Hui-Zheng, and Xu, Li

Subjects
China -- Environmental aspects, Data integrity -- Evaluation, Meteorological research -- Information management, Algorithms -- Usage, Solar radiation -- Influence, Solar radiation -- Environmental aspects, Data integrity, Company systems management, Algorithm, Earth sciences
Abstract

Solar radiation is one of the most important factors affecting climate and the environment. Routine measurements of irradiance are valuable for climate change research because of long time series and areal coverage. In this study, a set of quality assessment (QA) algorithms is used to test the quality of daily solar global, direct, and diffuse radiation measurements taken at 122 observatories in China during 1957-2000. The QA algorithms include a physical threshold test (QA1), a global radiation sunshine duration test (QA2), and a standard deviation test applied to time series of annually averaged solar global radiation (QA3). The results show that the percentages of global, direct, and diffuse solar radiation data that fail to pass QA1 are 3.07%, 0.01%, and 2.52%, respectively; the percentages of global solar radiation data that fail to pass the QA2 and QA3 are 0.77% and 0.49%, respectively. The method implemented by the Global Energy Balance Archive is also applied to check the data quality of solar radiation in China. Of the 84 stations with a time series longer that 20 yr, suspect data at 35 of the sites were found. Based on data that passed the QA tests, trends in ground solar radiation and the effect of the data quality assessment on the trends are analyzed. There is a decrease in ground solar global and direct radiation in China over the years under study. Although the quality assessment process has significant effects on the data from individual stations and/or time periods, it does not affect the long-term trends in the data.

Published
2008

24. From dimming to brightening: decadal changes in solar radiation at earth's surface

Author

Wild, Martin, Gilgen, Hans, Roesch, Andreas, Ohmura, Atsumu, Long, Charles N., Dutton, Ellsworth G., Forgan, Bruce, Kallis, Ain, Russak, Viivi, and Tsvetkov, Anatoly

Subjects
Greenhouse effect -- Research -- Analysis -- Measurement, Solar radiation -- Measurement -- Research -- Analysis -- Observations, Earth -- Research -- Measurement -- Analysis, Science and technology
Abstract

Variations in solar radiation incident at Earth's surface profoundly affect the human and terrestrial environment. A decline in solar radiation at land surfaces has become apparent in many observational records up to 1990, a phenomenon known as global dimming. Newly available surface observations from 1990 to the present, primarily from the Northern Hemisphere, show that the dimming did not persist into the 1990s. Instead, a widespread brightening has been observed since the late 1980s. This reversal is reconcilable with changes in cloudiness and atmospheric transmission and may substantially affect surface climate, the hydrological cycle, glaciers, and ecosystems., Solar radiation at Earth's surface (also known as global radiation or insolation) is the primary energy source for life on our planet. Widespread measurements of this quantity began in the [...]

Published
2005

28. Baseline surface radiation network (BSRN/WCRP): new precision radiometry for climate research

Author

Ohmura, Atsumu, Dutton, Ellsworth G., Forgan, Bruce, Frohlich, Claus, Gilgen, Hans, Hegner, Herman, Heimo, Alain, Konig-Langlo, Gert, McArthur, Bruce, Muller, Guido, Philipona, Rolf, Pinker, Rachel, Whitlock, Charlie H., Dehne, Klaus, and Wild, Martin

Subjects
Radiation -- Measurement, Radiometers -- Innovations, Climatology -- Research, Business, Earth sciences
Abstract

To support climate research, the World Climate Research Programme (WCRP) initiated a new radiometric network, the Baseline Surface Radiation Network (BSRN). The network aims at providing validation material for satellite radiometry and climate models. It further aims at detecting long-term variations in irradiances at the earth's surface, which are believed to play an important role in climate change. The network and its instrumentation are designed 1) to cover major climate zones, 2) to provide the accuracy required to meet the objectives, and 3) to ensure homogenized standards for a long period in the future. The limits of the accuracy are defined to reach these goals. The suitable instruments and instrumentations have been determined and the methods for observations and data management have been agreed on at all stations. Measurements of irradiances are at 1 Hz, and the 1-min statistics (mean, standard deviation, and extreme values) with quality flags are stored at a centralized data archive at the WCRP's World Radiation Monitoring Center (WRMC) in Zurich, Switzerland. The data are quality controlled both at stations and at the WRMC. The original 1-min irradiance statistics will be stored at the WRMC for 10 years, while hourly mean values will be transferred to the World Radiation Data Center in St. Petersburg, Russia. The BSRN, consisting of 15 stations, covers the earth's surface from 80 [degrees] N to 90 [degrees] S, and will soon be joined by seven more stations. The data are available to scientific communities in various ways depending on the communication environment of the users. The present article discusses the scientific base, organizational and technical aspects of the network, and data retrieval methods; shows various application possibilities; and presents the future tasks to be accomplished.

Published
1998

32. Baseline Surface Radiation Network (BSRN): structure and data description (1992-2017)

Author

Driemel, Amelie, Augustine, John, Behrens, Klaus, Colle, Sergio, Cox, Christopher, Cuevas-Agullo, Emilio, Denn, Fred M., Duprat, Thierry, Fukuda, Masato, Grobe, Hannes, Haeffelin, Martial, Hodges, Gary, Hyett, Nicole, Ijima, Osamu, Kallis, Ain, Knap, Wouter, Kustov, Vasilii, Long, Charles N., Longenecker, David, Lupi, Angelo, Maturilli, Marion, Mimouni, Mohamed, Ntsangwane, Lucky, Ogihara, Hiroyuki, Olano, Xabier, Olefs, Marc, Omori, Masao, Passamani, Lance, Pereira, Enio Bueno, Schmithüsen, Holger, Schumacher, Stefanie, Sieger, Rainer, Tamlyn, Jonathan, Vogt, Roland, Vuilleumier, Laurent, Xia, Xiangao, Ohmura, Atsumu, and König-Langlo, Gert

Abstract

Small changes in the radiation budget at the earth's surface can lead to large climatological responses when persistent over time. With the increasing debate on anthropogenic influences on climatic processes during the 1980s the need for accurate radiometric measurements with higher temporal resolution was identified, and it was determined that the existing measurement networks did not have the resolution or accuracy required to meet this need. In 1988 the WMO therefore proposed the establishment of a new international Baseline Surface Radiation Network (BSRN), which should collect and centrally archive high-quality ground-based radiation measurements in 1min resolution. BSRN began its work in 1992 with 9 stations; currently (status 2018-01-01), the network comprises 59 stations (delivering data to the archive) and 9 candidates (stations recently accepted into the network with data forthcoming to the archive) distributed over all continents and oceanic environments. The BSRN database is the World Radiation Monitoring Center (WRMC). It is hosted at the Alfred Wegener Institute (AWI) in Bremerhaven, Germany, and now offers more than 10300 months of data from the years 1992 to 2017. ISSN:1866-3516 ISSN:1866-3508

Published
2018

34. Das Baseline Surface Radiation Network

Author

Rapp, Jörg, König-Langlo, Gert, Driemel, Amelie, Ohmura, Atsumu, Rapp, Jörg, König-Langlo, Gert, Driemel, Amelie, and Ohmura, Atsumu

Published
2018

35. Observed Mass Balance of Mountain Glaciers and Greenland Ice Sheet in the 20th Century and the Present Trends

Author

Ohmura, Atsumu and Ohmura, Atsumu

Abstract

Glacier mass balance and secular changes in mountain glaciers and ice caps are evaluated from the annual net balance of 137 glaciers from 17 glacierized regions of the world. Further, the winter and summer balances for 35 glaciers in 11 glacierized regions are analyzed. The global means are calculated by weighting glacier and regional surface areas. The area-weighted global mean net balance for the period 1960-2000 is −270±34mma−1w.e. (water equivalent, in mm per year) or (−149±19km3a−1w.e.), with a winter balance of 890±24mma−1w.e. (490±13km3a−1w.e.) and a summer balance of −1,175±24mma−1w.e. (−647±13km3a−1w.e.). The linear-fitted global net balance is accelerating at a rate of −9±2.1 mm a−2. The main driving force behind this change is the summer balance with an acceleration of −10±2.0mm a−2. The decadal balance, however, shows significant fluctuations: summer melt reached its peak around 1945, followed by a decrease. The negative trend in the annual net balance is interrupted by a period of stagnation from 1960s to 1980s. Some regions experienced a period of positive net balance during this time, for example, Europe. The balance has become strongly negative since the early 1990s. These decadal fluctuations correspond to periods of global dimming (for smaller melt) and global brightening (for larger melt). The total radiation at the surface changed as a result of an imbalance between steadily increasing greenhouse gases and fluctuating aerosol emissions. The mass balance of the Greenland ice sheet and the surrounding small glaciers, averaged for the period of 1950-2000, is negative at −74±10 mma−1w.e. (−128±18km3a−1w.e.) with an accumulation of 297±33mma−1w.e. (519±58km3a−1w.e.), melt ablation −169±18mma−1w.e. (−296±31km3a−1w.e.), calving ablation −181±19mma−1w.e. (−316±33km3a−1w.e.) and the bottom melt-21±2mma−1w.e. (−35±4km3a−1w.e.). Almost half (−60±3km3a−1) of the net mass loss comes from mountain glaciers and ice caps around the ice sheet. At present, it is d

Published
2018

36. Enhanced temperature variability in high-altitude climate change

Author

Ohmura, Atsumu and Ohmura, Atsumu

Abstract

In the present article, monthly mean temperature at 56 stations assembled in 18 regional groups in 10 major mountain ranges of the world were investigated. The periods of the analysis covered the last 50 to 110years. The author found that the variability of temperature in climatic time scale tends to increase with altitude in about 65% of the regional groups. A smaller number of groups, 20%, showed the fastest change at an intermediate altitude between the peaks (or ridges) and their foot, while the remaining small number of sites, 15%, showed the largest trends at the foot of mountains. This tendency provides a useful base for considering and planning the climate impact evaluations. The reason for the amplification of temperature variation at high altitudes is traced back to the increasing diabatic processes in the mid- and high troposphere as a result of the cloud condensation. This situation results from the fact that the radiation balance at the earth's surface is transformed more efficiently into latent heat of evaporation rather than sensible heat, the ratio between them being 4 to 1. Variation in the surface evaporation is converted into heat upon condensation into cloud particles and ice crystals in the mid- and high troposphere. Therefore, this is the altitude where the result of the surface radiation change is effectively transferred. Further, the low temperature of the environment amplifies the effect of the energy balance variation on the surface temperature, as a result of the functional shape of Stefan-Boltzmann law. These processes altogether contribute to enhancing temperature variability at high altitudes. The altitude plays an important role in determining the temperature variability, besides other important factors such as topography, surface characteristics, cryosphere/temperature feedback and the frequency and intensity of an inversion. These processes have a profound effect not only on the ecosystem but also on glaciers and permafrost

Published
2018

37. 現温暖化におけるエアロゾルの効果

Author

Ohmura, Atsumu

Abstract

Ⅶ. エアロゾルの気候影響, The cause for the global temperature change of the last one hundred years is investigated in light of the earth’s energy balance. The material used for the present paper is mostly observed at the earth’s surface or from the space. While the enhanced greenhouse effect steadily increased,the aerosol effect fluctuated as a result of the decadal variation in aerosol emission. A cooling period witnessed for 30 years in the middle of the 20th Century is considered to have been caused by aerosol effect that surpassed the enhanced greenhouse effect. This cooling episode coincided with the period of declining surface global solar radiation,which was subsequently coined as the Global Dimming. The Mie-scattering theory can however explain only half of the decrease. The remaining half is considered due to the increase in cloud, which has been confirmed by the observations at the surface and from the space. Thus the ongoing climate warming is caused by a delicate imbalance between the increasing rates of greenhouse gases and of aerosol. The turning point of the total radiation from the negative to the positive phases is estimated to have happened sometime in the 1970s, which corresponds to the end of the cooling period and the beginning of the unprecedented warming. In the near future it is possible that the temperature trend may turn negative, if the aerosol effect overtakes the greenhouse effect. The currently observed slowing down of the warming after 2005 may well be the result of the increasing aerosol., 二十世紀初頭以来の百余年間は人為的温室効果による温暖化の時代と言われる. たしかに1900年以来全球平均でほぼ１℃昇温した. しかし, 温度変化を注意して見ると単調増加ではない. 1910年から30年間昇温した後, 1940年から1970年までの30年間昇温が停まっただけでなく, 0.1℃強寒冷化した. その後再び昇温に転じ1970年からの40年間だけで0.9℃温暖化した. これは全球平均の話で, この通りの変化を示した地域はないが, 二十世紀初期の温暖化と, それに続く寒冷化そして最近の顕著な温暖化という三相変化は位相をわずかに異にしてほぼ全球で見られる. 従って, 二十世紀中葉に現れた寒冷化は全球的現象であった. この30年にわたる全球規模での温暖化トレンドからの逸出はENSOやその他多く知られている振動現象では説明できない. この寒冷化の原因が分からなければ二十世紀全般にわたる温度変化の原因も正確には理解できないことになり, 又将来の予測もおぼつかないことになる. したがって, 本論文では, 二相の温暖化に挟まれた寒冷化の原因を極める. そのために, 本論文では甚だ基礎的になるが気候システムにおける温度生成過程を熱力学第一法則に基づいて考える. 地球表面の温度生成における放射の占める役割を認識し, 二十世紀初頭以来観測された全天太陽放射, 直達放射と大気の透過度を分析する. 全天太陽放射の経年変化から二十世紀初頭から1950年にかけての第一次グローバル・ブライトニング（全天太陽放射の増加期）,1950年代から80年代にかけてのグローバル・デイミング（全天太陽放射の減少期）, 更に80年代から2005年にかけての第二次グローバル・ブライトニングの３時代が認識される. その間に観測されたデイミングとブライトニング間の大気の透過度の変化は0.05であった. この透過度の変化に相当するエアロゾルの直接効果（ミー散乱）だけでは全天放射の変動量の約50％しか再現できないことが判り, 残りの50％はエアロゾルの間接効果,即ち雲の経年変化に帰着される. エアロゾルによる光学行程と雲量の相関はきわめて高く, この時期のエアロゾル間接効果と思われる雲の変動は全雲量で４％, 日照時間では日に0.4時間に相当する. この雲量の変動は地上と衛星から観測された結果である. グローバル・デイミングの続いていた期間は全天太陽放射の減少率が長波放射の増加率を上回り全放射率が減少していたことが判明し, これが気温低下を引き起こしたと考えられる. 続く1980年代からの第二次グローバル・ブライトニング期では増加に転じた全天太陽放射と既に増加傾向にあった長波放射が相まって全放射の増加率は6.6Wm-2/decadeとなり, 年間0.035℃となる観測時代最大の気温上昇率をもたらす結果となる. このように現在進行中の温暖化は温室効果ガスの増加率とエアロゾルの増加率のバランスの微妙な崩れの結果であり, 近い将来においてもエアロゾルの増加率がある程度大きくなり温室効果の上昇率を越すことが生じれば, 寒冷化が起こりえる. 現に2000年代に入ってから温暖化が鈍っているのは, 決して温室効果が減少したためではなく, エアロゾルの効果が増加している結果である可能性が高い.

Published
2014

38. Baseline Surface Radiation Network (BSRN): structure and data description (1992–2017)

Author

Driemel, Amelie, primary, Augustine, John, additional, Behrens, Klaus, additional, Colle, Sergio, additional, Cox, Christopher, additional, Cuevas-Agulló, Emilio, additional, Denn, Fred M., additional, Duprat, Thierry, additional, Fukuda, Masato, additional, Grobe, Hannes, additional, Haeffelin, Martial, additional, Hodges, Gary, additional, Hyett, Nicole, additional, Ijima, Osamu, additional, Kallis, Ain, additional, Knap, Wouter, additional, Kustov, Vasilii, additional, Long, Charles N., additional, Longenecker, David, additional, Lupi, Angelo, additional, Maturilli, Marion, additional, Mimouni, Mohamed, additional, Ntsangwane, Lucky, additional, Ogihara, Hiroyuki, additional, Olano, Xabier, additional, Olefs, Marc, additional, Omori, Masao, additional, Passamani, Lance, additional, Pereira, Enio Bueno, additional, Schmithüsen, Holger, additional, Schumacher, Stefanie, additional, Sieger, Rainer, additional, Tamlyn, Jonathan, additional, Vogt, Roland, additional, Vuilleumier, Laurent, additional, Xia, Xiangao, additional, Ohmura, Atsumu, additional, and König-Langlo, Gert, additional

Published
2018
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40. Author Correction: Volcanic influence on centennial to millennial Holocene Greenland temperature change

Author

Kobashi, Takuro, primary, Menviel, Laurie, additional, Jeltsch-Thömmes, Aurich, additional, Vinther, Bo M., additional, Box, Jason E., additional, Muscheler, Raimund, additional, Nakaegawa, Toshiyuki, additional, Pfister, Patrik L., additional, Döring, Michael, additional, Leuenberger, Markus, additional, Wanner, Heinz, additional, and Ohmura, Atsumu, additional

Published
2018
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44. Volcanic influence on centennial to millennial Holocene Greenland temperature change

Author

Kobashi, Takuro, Menviel, Laurie, Jeltsch-Thommes, Aurich, Vinther, Bo M., Box, Jason E., Muscheler, Raimund, Nakaegawa, Toshiyuki, Pfister, Patrik L., Doring, Michael, Leuenberger, Markus, Wanner, Heinz, Ohmura, Atsumu, Kobashi, Takuro, Menviel, Laurie, Jeltsch-Thommes, Aurich, Vinther, Bo M., Box, Jason E., Muscheler, Raimund, Nakaegawa, Toshiyuki, Pfister, Patrik L., Doring, Michael, Leuenberger, Markus, Wanner, Heinz, and Ohmura, Atsumu

Published
2017

48. Volcanic influence on centennial to millennial Holocene Greenland temperature change

Author

Kobashi, Takuro, primary, Menviel, Laurie, additional, Jeltsch-Thömmes, Aurich, additional, Vinther, Bo M., additional, Box, Jason E., additional, Muscheler, Raimund, additional, Nakaegawa, Toshiyuki, additional, Pfister, Patrik L., additional, Döring, Michael, additional, Leuenberger, Markus, additional, Wanner, Heinz, additional, and Ohmura, Atsumu, additional

Published
2017
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