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1. Digital Twin Earth -- Coasts: Developing a fast and physics-informed surrogate model for coastal floods via neural operators

Author

Jiang, Peishi, Meinert, Nis, Jordão, Helga, Weisser, Constantin, Holgate, Simon, Lavin, Alexander, Lütjens, Björn, Newman, Dava, Wainwright, Haruko, Walker, Catherine, and Barnard, Patrick

Subjects
Physics - Atmospheric and Oceanic Physics
Abstract

Developing fast and accurate surrogates for physics-based coastal and ocean models is an urgent need due to the coastal flood risk under accelerating sea level rise, and the computational expense of deterministic numerical models. For this purpose, we develop the first digital twin of Earth coastlines with new physics-informed machine learning techniques extending the state-of-art Neural Operator. As a proof-of-concept study, we built Fourier Neural Operator (FNO) surrogates on the simulations of an industry-standard flood and ocean model (NEMO). The resulting FNO surrogate accurately predicts the sea surface height in most regions while achieving upwards of 45x acceleration of NEMO. We delivered an open-source \textit{CoastalTwin} platform in an end-to-end and modular way, to enable easy extensions to other simulations and ML-based surrogate methods. Our results and deliverable provide a promising approach to massively accelerate coastal dynamics simulators, which can enable scientists to efficiently execute many simulations for decision-making, uncertainty quantification, and other research activities.

Published
2021

4. Tectonic influences on late Holocene relative sea levels from the central-eastern Adriatic coast of Croatia

Author

Shaw, Timothy A., Plater, Andrew J, Kirby, Jason R, Roy, Keven, Holgate, Simon, Tutman, Pero, Cahill, Niamh, Horton, Benjamin P., Shaw, Timothy A., Plater, Andrew J, Kirby, Jason R, Roy, Keven, Holgate, Simon, Tutman, Pero, Cahill, Niamh, and Horton, Benjamin P.

Abstract

Differential tectonic activity is a key factor responsible for variable relative sea-level (RSL) changes during the late Holocene in the Adriatic. Here, we compare reconstructions of RSL from the central-eastern Adriatic coast of Croatia with ICE-7G_NA (VM7) glacial-isostatic model RSL predictions to assess underlying driving mechanisms of RSL change during the past ~ 2700 years. Local standardized published sea-level index points (n ¼ 23) were combined with a new salt-marsh RSL reconstruction and tide-gauge measurements. We enumerated fossil foraminifera from a short salt-marsh sediment core constrained vertically by modern foraminiferal distributions, and temporally by radiometric analyses providing subcentury resolution within a Bayesian age-depth framework. We modelled changes in RSL using an ErrorsIn-Variables Integrated Gaussian Process (EIV-IGP) model with full consideration of the available uncertainty. Previously established index points show RSL rising from 1.48 m at 715 BCE to 1.05 m by 100 CE at 0.52 mm/yr (0.82-1.87 mm/yr). Between 500 and 1000 CE RSL was 0.7 m below present rising to 0.25 m at 1700 CE. RSL rise decreased to a minimum rate of 0.13 mm/yr (0.37-0.64 mm/yr) at ~1450 CE. The salt-marsh reconstruction shows RSL rose ~0.28 m since the early 18th century at an average rate of 0.95 mm/yr. Magnitudes and rates of RSL change during the twentieth century are concurrent with long-term tide-gauge measurements, with a rise of ~1.1 mm/yr. Predictions of RSL from the ICE-7G_NA (VM7) glacial-isostatic model (0.25 m at 715 BCE) are consistently higher than the reconstruction (1.48 m at 715 BCE) during the Late Holocene suggesting a subsidence rate of 0.45 ± 0.6 mm/yr. The new salt-marsh reconstruction and regional index points coupled with glacial-isostatic and statistical models estimate the magnitude and rate of RSL change and subsidence caused by the Adriatic tectonic framework.

Published
2018

6. State of the Climate in 2010

Author

Achberger, Christine, Ackerman, Steven A., Ahlstrom, A., Alfaro, Eric J., Allan, Robert J., Alves, Robert J., Amador, Jorge A., Amelie, Vincent, Andrianjafinirina, Solonomenjanahary, Antonov, John, Arndt, Derek S., Ashik, Igor, Atheru, Zachary, Attaher, Samar M., Baez, Julian, Banzon, Viva, Baringer, Molly O., Barreira, Sandra, Barriopedro, David, Barthia, Pawan K., Beal, Lisa M., Becker, Andreas, Behrenfeld, Michael J., Bell, Gerald D., Belward, Alan S., Benedetti, Angela, Berrisford, Paul, Berry, David I., Beszczynska-Moeller, Agnieszka, Bhatt, Uma S., Bidegain, Mario, Bindoff, Nathaniel L., Bissolli, Peter, Blake, Eric S., Blunden, Jessica, Booneeady, Prithiviraj, Bosilovich, Michael G., Boudet, Dagne R., Box, Jason E., Boyer, Timothy P., Bromwich, David H., Brown, Ross, Bryden, Harry L., Bulygina, Olga N., Burrows, John, Butler, J., Cais, Philippe, Calderon, Blanca, Callaghan, T. V., Camargo, Suzana J., Cappelen, John, Carmack, Eddy, Chambers, Don P., Chelliah, Muthuvel, Chidichimo, Maria P., Christiansen, H., Christy, John, Coehlo, Caio A. S., Colwell, Steve, Comiso, Josefino C., Compo, Gilber P., Crouch, Jake, Cunningham, Stuart A., Cutie, Virgen C., Dai, Aiguo, Davydova-Belitskaya, Valentina, Jeu, Richard, Decker, David, Dee, Dick, Demircan, M., Derksen, Chris, Diamond, Howard J., Dlugokencky, Howard, Dohan, Kathleen, Dolman, A. Johannes, Dorigo, Wouter, Drozdov, Dmitry S., Durack, Paul J., Dutton, Geoffrey S., Easterling, David, Ebita, Ayataka, Eischeid, Jon, Elkins, James W., Epstein, Howard E., Euscategui, Christian, Faijka-Williams, Eleanor, Famiglietti, James S., Faniriantsoa, Rija, Feely, Richard A., Fekete, Balazs M., Fenimore, Chris, Fettweis, Xavier, Field, Eric, Fioletov, Vitali E., Fogarty, Vitali E., Fogt, Ryan L., Forbes, B. C., Foster, Michael J., Frajka-Williams, E., Free, Melissa, Frolov, Ivan, Ganesan, A. L., Ganter, Catherine, Gibney, Ethan J., Gill, Stephen, Gill, M., Gitau, Wilson, Gleason, Karin L., Gobron, Nadine, Goldenberg, Stanley B., Goni, Gustavo J., Gonzalez, Idelmis G., Good, Simon A., Gottschalck, Jonathan, Gould, William A., Gouveia, Celia M., Griffiths, Georgina M., Guard, Chip, Guevara, Vladimir V., Haas, C., Hall, Bradley D., Halpert, Michael S., Heidinger, Andrew K., Heil, A., Heim, Richard R., Hennon, Paula A., Henry, Greg H. R., Hidalgo, Hugo G., Hilburn, Kyle, Hirschi, Joel J. M., Ho, Shu-Peng, Hobgood, Jay S., Hoerling, Martin, Holgate, Simon, Hook, Simon J., Hugony, Sebastien, Hurst, D., Ishihara, Hiroshi, Itoh, M., Jaimes, Ena, Jeffries, Martin, Jia, Gensu J., Jin, Xiangze, John, William E., Johnson, Bryan, Johnson, Gregory C., Jones, Philip D., Jumaux, Guillaume, Kabidi, Khadija, Kaiser, Johannes W., Kanzow, Torsten O., Kaplan, Alexey, Kearns, Edward J., Keller, Linda M., Kennedy, John J., Khatiwala, Samar, Kholodov, Alexander, Khoshkam, Mahbobeh, Kikuchi, T., Kimberlain, Todd B., Knaff, John A., Kobayashi, Shinya, Kokelj, Steve V., Korshunova, Natalia N., Kratz, David P., Krishfield, Richard, Kruger, Andries, Kruk, Michael C., Kumar Arun, Lammers, Richard B., Lander, Mark A., Landsea, Chris W., Lantuit, Hugues, Lantz, Trevor C., Lapinel, Braulio P., Lareef, Zubair, Lazzara, Matthew A., Leon, Antonia L., Leon, Gloria, Lauliette, Eric, Levitus, Sydney, Levy, Joel M., L Heureux, Michelle, Lin, I. I., Liu, Hongxing, Liu, Yanju, Liu, Yi, Loeb, Norman G., Long, Craig S., Lorrey, Andrew M., Lumpkin, Rick, Luo, Jing-Jia, Lyman, John M., Macdonald, Alison M., Maddux, Brent C., Maier, Frank, Malkova, Galina, Marchenko, Sergey, Marengo, Jose A., Maritorena, Stephane, Marotzke, Jochem, Martinez Guingla, Rodney, Maslanik, Jochem, Masson, Robert A., Mcbride, Charlotte, Mcgree, Simon, Mclaughlin, Fiona, Mcpeters, Rich, Mcvicar, Tim R., Mears, Carl A., Medany, Mahmoud A., Meier, Walt, Meinen, Christopher S., Merrifield, Mark A., Miller, Laury, Mitchum, Gary T., Montzka, Steve, Morcrette, Jean-Jacques, Mote, Thomas, Muhle, Jens, Mullan, A. Brett, Murray, Don, Nash, Eric R., Nerem, Steven R., Newman, Paul A., Nishino, S., Njau, Leonard, Noetzli, J., Oberbauer, S. F., Oberman, Naum, Obregon, Andre, Ogallo, Laban, Oludhe, Christopher, O Malley, Robert T., Overland, James, Park, Geun-Ha, Parker, David E., Pasch, Richard J., Pegion, Phil, Peltier, Alexandre, Pelto, Mauri S., Penalba, Olga C., Perez, Ramon S., Perlwitz, Judith, Perovich, Donald, Peterson, Thomas C., Pezza, Alexandre B., Phillips, David, Pinzon, Jorge E., Pitts, Michael C., Proshutinsky, A., Quegan, S., Quintana, Juan, Quintero, Alexander, Rabe, B., Rahimzadeh, Fatemeh, Rajeevan, Madhavan, Rayner, Darren, Rayner, Nick A., Raynolds, Martha K., Razuvaev, Vyacheslav N., Reagan, James R., Reid, Phillip, Renwick, James A., Revadekar, Jayashree, Reynolds, Richard W., Richter-Menge, Jacqueline, Rignot, Eric, Robinson, David A., Rodell, Matthew, Rogers, Mark, Romanovsky, Vladimir, Romero-Cruz, Fernando, Ronchail, Josyane, Rosenlof, Karen, Rossi, Shawn, Rutledge, Glenn, Saatchi, Sassan, Sabine, Christopher L., Saha, Suranjana, Sanchez-Lugo, Ahira, Santee, Michelle L., Sato, Hitoshi, Sawaengphokhai, P., Sayouri, Amal, Scambos, Ted A., Schauer, U., Schemm, Jae, Schmid, Claudia, Schneider, Philipp, Schueller, Dominique, Sensoy, Serhat, Sharp, Martin, Shaver, Gus R., Shiklomanov, Alexander, Shiklomanov, N., Shimada, Koji, Siegel, David A., Simmons, Adrian, Skansi, Maria, Smith, Adam, Smith, Cathy, Smith, S., Smith, Thomas M., Sokolov, Vladimir, Spence, Jacqueline M., Srivastava, Arvind Kumar, Stackhouse, Paul W., Stammerjohn, Sharon, Steele, Mike, Steinbrecht, Wolfgang, Stephenson, Tannecia S., Stolarski, Richard S., Tahani, Lloyd, Takahashi, Taro, Taylor, Michael A., Thepaut, Jean-Noel, Thiaw, Wassila M., Thorne, Peter W., Timmermans, M. L., Tobin, Skie, Toole, John, Trewin, Blair C., Trigo, Ricardo M., Tucker, Compton J., Tweedie, Craig E., As, D., Wal, R. S. W., A, Ronald J., Werf, G. R., Vautard, Robert, Vieira, G., Vincent, Lucie A., Vinther, Lucie A., Vinther, B., Vose, Russell, Wagner, Wolfgang, Wahr, John, Walker, David A., Walsh, John, Wang, Chunzai, Wang, Junhong, Wang, Lei, Wang, Muyin, Wang, Sheng-Hung, Wanninkhof, Rik, Weaver, Scott, Webber, Patrick J., Weber, Mark, Weller, Robert A., Weyman, James, Whitewood, Robert, Wijffels, Susan E., Wilber, Anne C., Willett, Katharine M., Williams, W., Willis, Joshua K., Wolken, Gabriel, Wong, Takmeng, Woodgate, Rebecca, Woodworth, Philip, Wovrosh, Alex J., Xue, Yan, Michiyo Yamamoto-Kawai, Yin, Xungang, Yu, Lisan, Zhang, Liangying, Zhang, Peiqun, Zhao, L., Zhou, Xinjia, and Zimmermann, S.

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, 13. Climate action, Earth science, Environmental science, Thermal state, 14. Life underwater, 010502 geochemistry & geophysics, 16. Peace & justice, Permafrost, 01 natural sciences, 0105 earth and related environmental sciences
Abstract

Several large-scale climate patterns influenced climate conditions and weather patterns across the globe during 2010. The transition from a warm El Niño phase at the beginning of the year to a cool La Niña phase by July contributed to many notable events, ranging from record wetness across much of Australia to historically low Eastern Pacific basin and near-record high North Atlantic basin hurricane activity. The remaining five main hurricane basins experienced below- to well-below-normal tropical cyclone activity. The negative phase of the Arctic Oscillation was a major driver of Northern Hemisphere temperature patterns during 2009/10 winter and again in late 2010. It contributed to record snowfall and unusually low temperatures over much of northern Eurasia and parts of the United States, while bringing above-normal temperatures to the high northern latitudes. The February Arctic Oscillation Index value was the most negative since records began in 1950. The 2010 average global land and ocean surface temperature was among the two warmest years on record. The Arctic continued to warm at about twice the rate of lower latitudes. The eastern and tropical Pacific Ocean cooled about 1°C from 2009 to 2010, reflecting the transition from the 2009/10 El Niño to the 2010/11 La Niña. Ocean heat fluxes contributed to warm sea surface temperature anomalies in the North Atlantic and the tropical Indian and western Pacific Oceans. Global integrals of upper ocean heat content for the past several years have reached values consistently higher than for all prior times in the record, demonstrating the dominant role of the ocean in the Earth's energy budget. Deep and abyssal waters of Antarctic origin have also trended warmer on average since the early 1990s. Lower tropospheric temperatures typically lag ENSO surface fluctuations by two to four months, thus the 2010 temperature was dominated by the warm phase El Niño conditions that occurred during the latter half of 2009 and early 2010 and was second warmest on record. The stratosphere continued to be anomalously cool. Annual global precipitation over land areas was about five percent above normal. Precipitation over the ocean was drier than normal after a wet year in 2009. Overall, saltier (higher evaporation) regions of the ocean surface continue to be anomalously salty, and fresher (higher precipitation) regions continue to be anomalously fresh. This salinity pattern, which has held since at least 2004, suggests an increase in the hydrological cycle. Sea ice conditions in the Arctic were significantly different than those in the Antarctic during the year. The annual minimum ice extent in the Arctic—reached in September—was the third lowest on record since 1979. In the Antarctic, zonally averaged sea ice extent reached an all-time record maximum from mid-June through late August and again from mid-November through early December. Corresponding record positive Southern Hemisphere Annular Mode Indices influenced the Antarctic sea ice extents. Greenland glaciers lost more mass than any other year in the decade-long record. The Greenland Ice Sheet lost a record amount of mass, as the melt rate was the highest since at least 1958, and the area and duration of the melting was greater than any year since at least 1978. High summer air temperatures and a longer melt season also caused a continued increase in the rate of ice mass loss from small glaciers and ice caps in the Canadian Arctic. Coastal sites in Alaska show continuous permafrost warming and sites in Alaska, Canada, and Russia indicate more significant warming in relatively cold permafrost than in warm permafrost in the same geographical area. With regional differences, permafrost temperatures are now up to 2°C warmer than they were 20 to 30 years ago. Preliminary data indicate there is a high probability that 2010 will be the 20th consecutive year that alpine glaciers have lost mass. Atmospheric greenhouse gas concentrations continued to rise and ozone depleting substances continued to decrease. Carbon dioxide increased by 2.60 ppm in 2010, a rate above both the 2009 and the 1980–2010 average rates. The global ocean carbon dioxide uptake for the 2009 transition period from La Niña to El Niño conditions, the most recent period for which analyzed data are available, is estimated to be similar to the long-term average. The 2010 Antarctic ozone hole was among the lowest 20% compared with other years since 1990, a result of warmer-than-average temperatures in the Antarctic stratosphere during austral winter between mid-July and early September.

Published
2011
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9. State of the Climate in 2012

Author

Blunden, Jessica, Arndt, Derek S., Achberger, Christine, Ackerman, Stephen A., Albanil, Adelina, Alexander, P., Alfaro, Eric J., Allan, Rob, Alves, Lincoln M., Amador, Jorge A., Ambenje, Peter, Andrianjafinirina, Solonomenjanahary, Antonov, John, Aravequia, Jose A., Arendt, A., Arevalo, Juan, Ashik, I., Atheru, Zachary, Banzon, Viva, Baringer, Molly O., Barreira, Sandra, Barriopedro, David E., Beard, Grant, Becker, Andreas, Behrenfeld, Michael J., Bell, Gerald D., Benedetti, Angela, Bernhard, Germar, Berrisford, Paul, Berry, David I., Bhatt, U., Bidegain, Mario, Bindoff, Nathan, Bissolli, Peter, Blake, Eric S., Booneeady, Raj, Bosilovich, Michael, Box, J. E., Boyer, Tim, Braathen, Geir O., Bromwich, David H., Brown, R., Brown, L., Bruhwiler, Lori, Bulygina, Olga N., Burgess, D., Burrows, John, Calderon, Blanca, Camargo, Suzana J., Campbell, Jayaka, Cao, Y., Cappelen, J., Carrasco, Gualberto, Chambers, Don P., Chang A, L., Chappell, Petra, Chehade, Wissam, Cheliah, Muthuvel, Christiansen, Hanne H., Christy, John R., Ciais, Phillipe, Coelho, Caio A. S., Cogley, J. G., Colwell, Steve, Cross, J. N., Crouch, Jake, Cunningham, Stuart A., Dacic, Milan, Jeu, Richard A. M., Dekaa, Francis S., Demircan, Mesut, Derksen, C., Diamond, Howard J., Dlugokencky, Ed J., Dohan, Kathleen, Dolman, A. Johannes, Domingues, Catia M., Dong Shenfu, Dorigo, Wouter A., Drozdov, D. S., Duguay, Claude R., Dunn, Robert J. H., Duran-Quesada, Ana M., Dutton, Geoff S., Ehmann, Christian, Elkins, James W., Euscategui, Christian, Famiglietti, James S., Fang Fan, Fauchereau, Nicolas, Feely, Richard A., Fekete, Balazs M., Fenimore, Chris, Fioletov, Vitali E., Fogarty, Chris T., Fogt, Ryan L., Folland, Chris K., Foster, Michael J., Frajka-Williams, Eleanor, Franz, Bryan A., Frith, Stacey H., Frolov, I., Ganter, Catherine, Garzoli, Silvia, Geai, M. -L, Gerland, S., Gitau, Wilson, Gleason, Karin L., Gobron, Nadine, Goldenberg, Stanley B., Goni, Gustavo, Good, Simon A., Gottschalck, Jonathan, Gregg, Margarita C., Griffiths, Georgina, Grooss, Jens-Uwe, Guard, Charles Chip, Gupta, Shashi K., Hall, Bradley D., Halpert, Michael S., Harada, Yayoi, Hauri, C., Heidinger, Andrew K., Heikkila, Anu, Heim, Richard R., Heimbach, Patrick, Hidalgo, Hugo G., Hilburn, Kyle, Ho, Shu-Peng, Hobbs, Will R., Holgate, Simon, Hovsepyan, Anahit, Hu Zeng-Zhen, Hughes, P., Hurst, Dale F., Ingvaldsen, R., Inness, Antje, Jaimes, Ena, Jakobsson, Martin, James, Adamu I., Jeffries, Martin O., Johns, William E., Johnsen, Bjorn, Johnson, Gregory C., Johnson, Bryan, Jones, Luke T., Jumaux, Guillaume, Kabidi, Khadija, Kaiser, Johannes W., Kamga, Andre, Kang, Kyun-Kuk, Kanzow, Torsten O., Kao, Hsun-Ying, Keller, Linda M., Kennedy, John J., Key, J., Khatiwala, Samar, Pour, H. Kheyrollah, Kholodov, A. L., Khoshkam, Mahbobeh, Kijazi, Agnes, Kikuchi, T., Kim, B. -M, Kim, S. -J, Kimberlain, Todd B., Knaff, John A., Korshunova, Natalia N., Koskela, T., Kousky, Vernon E., Kramarova, Natalya, Kratz, David P., Krishfield, R., Kruger, Andries, Kruk, Michael C., Kumar, Arun, Lagerloef, Gary S. E., Lakkala, K., Lander, Mark A., Landsea, Chris W., Lankhorst, Matthias, Laurila, T., Lazzara, Matthew A., Lee, Craig, Leuliette, Eric, Levitus, Sydney, L Heureux, Michelle, Lieser, Jan, Lin, I-I, Liu, Y. Y., Liu, Y., Liu Hongxing, Liu Yanju, Lobato-Sanchez, Rene, Locarnini, Ricardo, Loeb, Norman G., Loeng, H., Long, Craig S., Lorrey, Andrew M., Luhunga, P., Lumpkin, Rick, Luo Jing-Jia, Lyman, John M., Macdonald, Alison M., Maddux, Brent C., Malekela, C., Manney, Gloria, Marchenko, S. S., Marengo, Jose A., Marotzke, Jochem, Marra, John J., Martinez-Gueingla, Rodney, Massom, Robert A., Mathis, Jeremy T., Mcbride, Charlotte, Mccarthy, Gerard, Mcvicar, Tim R., Mears, Carl, Meier, W., Meinen, Christopher S., Menendez, Melisa, Merrifield, Mark A., Mitchard, Edward, Mitchum, Gary T., Montzka, Stephen A., Morcrette, Jean-Jacques, Mote, Thomas, Muehle, Jens, Muehr, Bernhard, Mullan, A. Brett, Mueller, Rolf, Nash, Eric R., Nerem, R. Steven, Newlin, Michele L., Newman, Paul A., Ng Ongolo, H., Nieto, Juan Jose, Nishino, S., Nitsche, Helga, Noetzli, Jeannette, Oberman, N. G., Obregon, Andre, Ogallo, Laban A., Oludhe, Christopher S., Omar, Mohamed I., Overland, James, Oyunjargal, Lamjav, Parinussa, Robert M., Park, Geun-Ha, Park, E-Hyung, David Berry, Pasch, Richard J., Pascual-Ramirez, Reynaldo, Pelto, Mauri S., Penalba, Olga, Peng, L., Perovich, Don K., Pezza, Alexandre B., Phillips, David, Pickart, R., Pinty, Bernard, Pitts, Michael C., Purkey, Sarah G., Quegan, Shaun, Quintana, Juan, Rabe, B., Rahimzadeh, Fatemeh, Raholijao, Nirivololona, Raiva, I., Rajeevan, Madhavan, Ramiandrisoa, Voahanginirina, Ramos, Alexandre, Ranivoarissoa, Sahondra, Rayner, Nick A., Rayner, Darren, Razuveav, Vyacheslav N., Reagan, James, Reid, Phillip, Renwick, James, Revedekar, Jayashree, Richter-Menge, Jacqueline, Rivera, Ingrid L., Robinson, David A., Rodell, Matthew, Romanovsky, Vladimir E., Ronchail, Josyane, Rosenlof, Karen H., Sabine, Christopher L., Salvador, Mozar A., Sanchez-Lugo, Ahira, Santee, Michelle L., Sasgen, I., Sawaengphokhai, P., Sayouri, Amal, Scambos, Ted A., Schauer, U., Schemm, Jae, Schlosser, P., Schmid, Claudia, Schreck, Carl, Semiletov, Igor, Send, Uwe, Sensoy, Serhat, Setzer, Alberto, Severinghaus, Jeffrey, Shakhova, Natalia, Sharp, M., Shiklomanov, Nicolai I., Siegel, David A., Silva, Viviane B. S., Silva, Frabricio D. S., Sima, Fatou, Simeonov, Petio, Simmonds, I., Simmons, Adrian, Skansi, Maria, Smeed, David A., Smethie, W. M., Smith, Adam B., Smith, Cathy, Smith, Sharon L., Smith, Thomas M., Sokolov, V., Srivastava, A. K., Stackhouse, Paul W., Stammerjohn, Sharon, Steele, M., Steffen, Konrad, Steinbrecht, Wolfgang, Stephenson, Tannecia, Su, J., Svendby, T., Sweet, William, Takahashi, Taro, Tanabe, Raymond M., Taylor, Michael A., Tedesco, Marco, Teng, William L., Thepaut, Jean-Noel, Thiaw, Wassila M., Thoman, R., Thompson, Philip, Thorne, Peter W., Timmermans, M. -L, Tobin, Skie, Toole, J., Trewin, Blair C., Trigo, Ricardo M., Trotman, Adrian, Tschudi, M., Wal, Roderik S. W., Werf, Guido R., Vautard, Robert, Vazquez, J. L., Vieira, Goncalo, Vincent, Lucie, Vose, Russ S., Wagner, Wolfgang W., Wahr, John, Walsh, J., Wang Junhong, Wang Chunzai, Wang, M., Wang Sheng-Hung, Wang Lei, Wanninkhof, Rik, Weaver, Scott, Weber, Mark, Werdell, P. Jeremy, Whitewood, Robert, Wijffels, Susan, Wilber, Anne C., Wild, J. D., Willett, Kate M., Williams, W., Willis, Joshua K., Wolken, G., Wong, Takmeng, Woodgate, R., Worthy, D., Wouters, B., Wovrosh, Alex J., Xue Yan, Yamada, Ryuji, Yin Zungang, Yu Lisan, Zhang Liangying, Zhang Peiqun, Zhao Lin, Zhao, J., Zhong, W., Ziemke, Jerry, Zimmermann, S., ICOS-ATC (ICOS-ATC), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Repositório da Universidade de Lisboa

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, 13. Climate action, Photosynthetically active radiation, Climate, Dynamics (mechanics), Data_FILES, Environmental science, Fraction (chemistry), 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Remote sensing
Abstract

For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.

Published
2013
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10. Global Sea-level Observing System (GLOSS) Implementation plan – 2012

Author

Merrifield, Mark, Holgate, Simon, Mitchum, Gary, Pérez, Begoña, Rickards, Lesley, Schöne, Tilo, Woodworth, Philip, Wöppelmann, Guy, Aarup, Thorkild, and Intergovernmental Oceanographic Commission

Subjects
Implementation plan, GLOSS, S::Sea level [ASFA_2015]
Abstract

The Global Sea-level Observing System (GLOSS) was established by the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in 1985 to provide oversight and coordination for global and regional sea-level networks in support of scien- tific research. The first GLOSS Implementation Plan (GIP) in 1990 established the GLOSS Core Network (GCN) of ~300 tide gauges distributed around the world, technical standards for GLOSS tide gauge stations, as well as the basic terms and obligations for Member States participating in GLOSS. The second GIP in 1997 expanded the GLOSS programme to include sub-networks focused on long historical records suitable for the detection of long-term sea- level trends and accelerations (GLOSS-LTT), a cali- bration network for satellite altimetry (GLOSS-ALT), and a network suitable for monitoring aspects of the global ocean circulation (GLOSS-OC). In addition, a strategy for integrating Global Positioning System (GPS) into monitoring of land levels at GLOSS tide gauges was developed. The focus of the GIP 2012 remains the GCN and the datasets that result from this network. The new plan calls for two significant upgrades to the GCN moti- vated by scientific and operational requirements: 1) all GCN stations are required to report data in near-real time, which will be tracked at a Sea-level Station Monitoring Facility. This will involve upgrades in power, data acquisition plat- forms, and communication packages; however, these upgrades are cost-effective in terms of the benefits that a real-time system will provide for ocean monitoring and improved station perfor- mance due to early detection of station malfunc- tions; 2) continuous measurements of the Global Navigation Satellite System (GNSS), in particular the U.S. Global Positioning System (GPS), the Russian GLONASS, or the newly established European GALILEO, or equivalent systems, in the vicinity of the tide gauge benchmark (TGBM) are required for all GCN stations. This upgrade will support satellite altimetry calibration and research efforts aimed at determining geocentric global sea-level rise rates as well as regional changes in sea level. Most relevant, vertical land movements can signifi- cantly alter the rates of sea-level rise expected from the sole climatic contributions of ocean ther- mal expansion and land-based ice melting, possi- bly magnifying the impacts of sea-level rise on the coast. In many cases, this requirement can be met by taking advantage of existing GNSS receivers maintained by other groups, as long as a precise geodetic tie to the GCN tide gauge can be made using, e.g. conventional levelling. The organization of the plan is as follows. An over- view of the GLOSS programme (chapter 1) and a brief summary of the uses of tide gauge data (chapter 2) are presented. The current status of the GLOSS programme is considered (chapter 3), followed by a discussion of the sea-level monitoring requirements raised by advisory groups and panels (chapter 4), as well as a self-assessment based on specific research and operational applications (chapter 5). These requirements are used to develop implementation goals for the GLOSS networks and data centres (chapter 6). Minor modifications are proposed for the administrative structure of GLOSS aimed at providing improved oversight of the imple- mentation plan (chapter 7). The success of the plan depends critically on the participation of Member States, whose obligations are summarized (chapter 8). The successful Training, Education and Mutual Assistance programmes that have been a corner stone of GLOSS will be continued to help meet implementation requirements (chapter 9). Additional technical and programmatic details are included in a set of appendices. OpenASFA input Published Refereed

Published
2012

11. The GLOSS Delayed Mode Data Centre and the GLOSS Implementation Plan 2012.

Author

BRADSHAW, ELIZABETH, RICKARDS, LESLEY, HOLGATE, SIMON, and AARUP, THORKILD

Subjects
SEA level, SERVER farms (Computer network management), QUALITY control, METADATA, BENCHMARKING (Management)
Abstract

The main component of the Global Sea Level Observing System (GLOSS) is the GLOSS Core Network (GCN) of 290 sea level stations. The present definition of the GCN (the definition is modified every few years) is called GLOSS10. In 2012 a new GLOSS implementation plan was developed to update technical standards for GLOSS tide gauge stations, as well as describing the basic terms and obligations for Member States participating in GLOSS. The British Oceanographic Data Centre (BODC) and the Permanent Service for Mean Sea Level (PSMSL) run the GLOSS Delayed Mode Data Centre jointly. It is responsible for assembling, quality controlling and distributing the "final" version of GLOSS sea level data sets and their supporting metadata, as well as carrying out data archaeology on historical analogue sea level records, preserving them in digital form. It also maintains the GLOSS Station Handbook and GLOSS website. [ABSTRACT FROM AUTHOR]

Published
2015
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12. Comment on 'A semi-empirical approach to projecting future sea-level rise'.

Author

Holgate, Simon, Jevrejeva, Svetlana, Woodworth, Philip, Brewer, Simon, Holgate, Simon, Jevrejeva, Svetlana, Woodworth, Philip, and Brewer, Simon

Abstract

Rahmstorf (Science, 19 January 2007,10.1126/science.1135456) presented an approach to the prediction of sea level rise based on a proposed linear relationship between global surface temperatures and the rate of global mean sea level change over the timescales relevant to humans - decades to centuries. We find no such linear relationship and, while agreeing that there is considerable uncertainty in the prediction of future sea level rise, consider that this approach does not meaningfully contribute to quantifying this uncertainty.

Published
2007

19. Reconstructing historical sea-level trends for the Croatian coast of the Adriatic Sea using salt-marsh foraminifera

Author

Shaw, Timothy, Plater, Andrew, Kirby, Jason, and Holgate, Simon

Subjects
550, G Geography (General)
Abstract

The application of salt-marsh foraminifera to reconstruct historical sea-level trends was investigated for the Croatian coast of the Adriatic Sea using a transfer function approach. This technique, whilst well practised from north Atlantic sites along the shores of America and UK, has previously evaded any published study in the Mediterranean region. A total of 70 surface samples were collected across separate transects established at two micro-tidal salt-marsh sites from the central Croatian coastline to establish a modern dataset of foraminifera. In addition, environmental variables were also investigated including salinity, pH, organic matter, particle size, distance (from open water) and altitude, relative to the Croatian national datum. Three sediment cores were sampled for fossil foraminifera and composite chronologies involving short-lived radionuclides, radiocarbon dating and pollution indicators from XRF. Age-depth models were created using classical and Bayesian approaches. Quantitative analysis of the foraminiferal assemblages revealed on average three faunal zones in which characteristic species occurred. This comprised a faunal zone composed almost exclusively of agglutinated species; J. macrescens, T. inflata and M. fusca extending between mean tidal level (MTL) and beyond MHWST (higher altitude). A second faunal zone was more variable and comprised of a mixed assemblage of agglutinated species described above in addition to calcareous species; Ammonia spp., Elphidium spp., Haynesina germanica and Quinqueloculina spp. This zone spanned a large vertical range above and below MTL. In a third faunal zone calcareous species dominated and was restricted to the lower altitudes of the salt-marsh environments. Further quantitative measures were employed to test the hypothesis that foraminiferal distributions were controlled by altitude. Partial ordination techniques revealed altitude as a statistically significant control confirming their suitability as proxies for sea-level in transfer function reconstructions. An analysis of species environment relationships revealed strong linear response suggesting the use of PLS regression models. Transfer functions were then developed for both site specific and a total combined dataset, where small r2 jack values largely reflected the short environmental gradients despite relatively low predictions errors (RMSEP jack = <0.11). The total combined dataset was chosen and screened to remove sample outliers improving model performance (r2 jack = 0.54 and RMSEP jack = 0.08). Finally, the transfer function model was applied to core sediments to reconstruct mean sea-level where an inflexion observed at AD 1940 showed acceleration comparable to other proxy reconstructions. Indeed this trend was similar to instrumental data from Trieste tide-gauge records. Similarly the transfer function reconstruction identifies the dramatic increases in MSL observed in both tide-gauge (Split and Trieste) and satellite observations since the early 1990s.

Published
2013
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20. Assessing the viability of using foraminifera from Mersey Estuary saltmarsh sediments to reconstruct former sea level

Author

Mills, Hayley, Plater, Andy., Kirby, Jason., and Holgate, Simon

Subjects
551.46
Abstract

The viability of using a foraminifera-based transfer function method to reconstruct the local relative sea-level for the Mersey Estuary was assessed in this study, which has not been previously investigated in the UK in the context of application in a strongly macrotidal setting. A total of 105 surface samples were collected across two saltmarshes. Foraminiferal analysis was carried out, along with several environmental variables (organic matter content, salinity, pH, and grain size) to establish the species distribution of foraminifera and their relationship with elevation. Two main zonations were found: a high-to-middle marsh zone occupied by Haplophragmoides spp., J. macrescens and M. fusca; and a low marsh zone composed of increasing numbers of calcareous species including Elphidium spp.; and Haynesina spp. Foraminiferal distributions along each transect were found to be controlled predominantly by elevation and distance from tidal influence, whilst combined datasets reflected intra- and inter-site variability in the assemblages. Elevation was still found to have an important control over the distributions, with a strong relationship between the species zonations and elevation (r2 = 0.8). Therefore, the dataset (82 samples) formed a local training set in which a transfer function for the relationship between foraminifera species and elevation was developed. WAPLS was used as it produced the highest predictive ability (r2 jack = 0.85) and lowest prediction errors (RMSEPjack = 0.11 m). Regional and combined (local plus regional) transfer functions were also developed but the local transfer function produced the most accurate and reliable reconstruction. Reconstructions were carried out for both saltmarshes with reference to a sediment chronology which was established using radionuclides and pollution indicators. The reconstructions demonstrated the vast difference in the saltmarsh development and record of sea level between the sites. Oglet Bay developed as a result of increased accommodation space arising from changing estuary morphology, resulting in rapid accretion (2.34 cm year-1) and was found to be strongly influenced by tidal channel migration. Decoy Marsh accreted at a slower pace (0.32 cm year-1) and was less affected by tidal or morphological changes. Both reconstructions were affected by decalcification resulting in the reconstructions dating back to 1978 at the most. The reconstructed rates of sea-level change were 1.8 cm year-1 for Oglet Bay and 1.1 cm year-1 for Decoy Marsh, both of which over-estimate the trend from the monthly instrumental record (1.04 cm year-1) over the same period. The study highlights the problems which may arise when conducting research in an inner estuary which is strongly macrotidal, including tidal range changes, tidal asymmetry, and decalcification, but also demonstrates that a relatively precise and reliable reconstruction is achievable.

Published
2011
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