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1. Regional characteristics of extreme precipitation events over Aotearoa New Zealand

Author

Gokul Vishwanathan, Adrian J. McDonald, Chris Noble, Dáithí A. Stone, Suzanne Rosier, Alex Schuddeboom, Peter Kreft, Gregor Macara, Trevor Carey-Smith, and Greg Bodeker

Subjects
Extreme precipitation, Extreme weather event database, Persistence, Aotearoa New Zealand, Meteorology. Climatology, QC851-999
Abstract

We document 1394 extreme precipitation events (EPEs) over Aotearoa New Zealand’s (ANZ) Regional Councils between March 1996 and December 2021. The characteristics of EPEs are documented using a novel spatio-temporal framework that diagnoses the peak intensity, duration, and accumulation of the EPE using the ERA-5 and MERRA-2 reanalysis products. Properties of EPEs were evaluated according to region across ANZ, and clear regional differences are highlighted. In particular, it is found that the duration of an EPE has a stronger influence than the peak intensity on the total accumulated precipitation across all regions and precipitation event types (large-scale or convective). Since larger precipitation accumulations have greater potential to cause extensive flooding over larger areas, an important implication is the need for numerical weather prediction in ANZ to forecast the duration of an intense precipitation event adequately in order to improve emergency preparedness.

Published
2024
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2. Southern Alps equilibrium line altitudes: four decades of observations show coherent glacier–climate responses and a rising snowline trend

Author

Andrew M. Lorrey, Lauren Vargo, Heather Purdie, Brian Anderson, Nicolas J. Cullen, Pascal Sirguey, Andrew Mackintosh, Andrew Willsman, Gregor Macara, and Warren Chinn

Subjects
Climate change, glacier monitoring, mountain glaciers, snow/ice surface processes, transient snowline, Environmental sciences, GE1-350, Meteorology. Climatology, QC851-999
Abstract

An end of summer snowline (EOSS) photographic dataset for Aotearoa New Zealand contains over four decades of equilibrium line altitude (ELA) observations for more than 50 index glaciers. This dataset provides an opportunity to create a climatological ELA reference series that has several applications. Our work screened out EOSS sites that had low temporal coverage and also removed limited observations when the official survey did not take place. Snowline data from 41 of 50 glaciers in the EOSS dataset were retained and included in a normalised master snowline series that spans 1977–2020. Application of the regionally representative normalised master snowline series in monthly and seasonally resolved climate response function analyses showed consistently strong relationships with austral warm-season temperatures for land-based stations west of the Southern Alps and the central Tasman Sea. There is a trend towards higher regional snowlines since the 1990s that has been steepening in recent decades. If contemporary decadal normalised master snowline series trends are maintained, the average Southern Alps snowline elevation will be displaced at least 200 m higher than normal by the 2025–2034 decade. More frequent extremely high snowlines are expected to drive more extreme cumulative mass-balance losses that will reduce the glacierised area of Aotearoa New Zealand.

Published
2022
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3. Regional Climates

Author

Peter Bissolli, Catherine Ganter, Tim Li, Ademe Mekonnen, Ahira Sánchez-Lugo, Eric J. Alfaro, Lincoln M. Alves, Jorge A. Amador, B. Andrade, Francisco Argeñalso, P. Asgarzadeh, Julian Baez, Reuben Barakiza, M. Yu. Bardin, Mikhail Bardin, Oliver Bochníček, Brandon Bukunt, Blanca Calderón, Jayaka D. Campbell, Elise Chandler, Ladislaus Chang’a, Vincent Y. S. Cheng, Leonardo A. Clarke, Kris Correa, Catalina Cortés, Felipe Costa, A.P.M.A. Cunha, Mesut Demircan, K. R. Dhurmea, A. Diawara, Sarah Diouf, Dashkhuu Dulamsuren, M. ElKharrim, Jhan-Carlo Espinoza, A. Fazl-Kazem, Chris Fenimore, Steven Fuhrman, Karin Gleason, Charles 'Chip' P. Guard, Samson Hagos, Mizuki Hanafusa, H. R. Hasannezhad, Richard R. Heim, Hugo G. Hidalgo, J. A. Ijampy, Gyo Soon Im, Annie C. Joseph, G. Jumaux, K. R. Kabidi, P-H. Kamsu-Tamo, John Kennedy, Valentina Khan, Mai Van Khiem, Philemon King’uza, Natalia N. Korshunova, A. C. Kruger, Hoang Phuc Lam, Mark A. Lander, Waldo Lavado-Casimiro, Tsz-Cheung Lee, Kinson H. Y. Leung, Gregor Macara, Jostein Mamen, José A. Marengo, Charlotte McBride, Noelia Misevicius, Aurel Moise, Jorge Molina-Carpio, Natali Mora, Awatif E. Mostafa, Habiba Mtongori, Charles Mutai, O. Ndiaye, Juan José Nieto, Latifa Nyembo, Patricia Nying’uro, Xiao Pan, Reynaldo Pascual Ramírez, David Phillips, Brad Pugh, Madhavan Rajeevan, M. L. Rakotonirina, Andrea M. Ramos, M. Robjhon, Camino Rodriguez, Guisado Rodriguez, Josyane Ronchail, Benjamin Rösner, Roberto Salinas, Hirotaka Sato, Hitoshi Sato, Amal Sayouri, Joseph Sebaziga, Serhat Sensoy, Sandra Spillane, Katja Trachte, Gerard van der Schrier, F. Sima, Adam Smith, Jacqueline M. Spence, O. P. Sreejith, A. K. Srivastava, José L. Stella, Kimberly A. Stephenson, Tannecia S. Stephenson, S. Supari, Sahar Tajbakhsh-Mosalman, Gerard Tamar, Michael A. Taylor, Asaminew Teshome, Wassila M. Thiaw, Skie Tobin, Adrian R. Trotman, Cedric J. Van Meerbeeck, A. Vazifeh, Shunya Wakamatsu, Wei Wang, Fei Xin, F. Zeng, Peiqun Zhang, and Zhiwei Zhu

Subjects
Atmospheric Science
Published
2021
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4. Predicting the climatic risk of myrtle rust during its first year in New Zealand

Author

Vijay Paul, Lorin L. Lima, Rebecca Martin, Andrew Tait, Robert M. Beresford, Gregor Macara, Zhidong D. Yu, and Richard Turner

Subjects
0106 biological sciences, Potential risk, Biosecurity, Horticulture, Biology, 010603 evolutionary biology, 01 natural sciences, Rust, Atmospheric research, Insect Science, Primary sector of the economy, Retrospective analysis, Period (geology), Mainland, Physical geography, Agronomy and Crop Science, 010606 plant biology & botany
Abstract

After the first detection of myrtle rust (Austropuccinia psidii) on mainland New Zealand in May 2017, the Ministry for Primary Industries sought information about how weather conditions would affect regional and seasonal risk of disease establishment to help plan the incursion response. Using internationally published information, a pathogen-process model was developed to predict infection, latent period and sporulation in relation to weather variables (temperature, relative humidity and solar radiation). This Myrtle Rust Process Model (MRPM) was implemented by the National Institute of Water and Atmospheric Research Limited using numerical weather model data to produce weekly maps of potential risk. Predicted risk was greatest in northern North Island and decreased further south, but was still substantial in coastal areas of the north-western South Island during summer and autumn. Risk was low in southern coastal areas of the South Island and the lowest risk occurred in mountainous areas, particularly in the South Island. Retrospective analysis of surveillance data showed that the MRPM accurately predicted geographic risk and it is currently in use for tactical planning of incursion surveillance and organism management.

Published
2018
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6. Soil moisture deficit selects for desiccation tolerant Rhizobium leguminosarum bv. trifolii

Author

Gregor Macara, Hayley J. Ridgway, Alasdair Noble, Maureen O'Callaghan, Ross Ballard, Steven A. Wakelin, Robert van Ham, and René Geurts

Subjects
0301 basic medicine, Soil biology, Desiccation tolerance, 030106 microbiology, Population, Soil Science, medicine.disease_cause, Pasture, White clover, Rhizobium leguminosarum, 03 medical and health sciences, Rhizobium leguminosarum bv. trifolii, medicine, Laboratorium voor Moleculaire Biologie, education, geography, education.field_of_study, geography.geographical_feature_category, Ecology, biology, food and beverages, 04 agricultural and veterinary sciences, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, Agricultural and Biological Sciences (miscellaneous), Agronomy, Soil water, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Rhizobium, bacteria, Soil moisture deficit, Laboratory of Molecular Biology, Desiccation, Nitrogen fixing symbiosis
Abstract

Tolerance to desiccation is a highly desirable attribute for Rhizobium spp., which are widely used as symbionts of pasture legumes. Poor survival of Rhizobium spp. is of particular concern during the commercial formulation and seed application phase, but also when sown into dry fields and during saprophytic survival. Efforts have been made to protect Rhizobium spp. from desiccation, either by use of desiccation protectants in formulations, or by triggering generalised mechanisms of cellular stress tolerance. This study looked at the potential to isolate desiccation tolerant strains of Rhizobium leguminosarum bv. trifolii that are intrinsically tolerant to desiccation. We investigated the influence of long term exposure to dry soil conditions, and rapid soil drying, as factors in selection of desiccation tolerance. Pasture soils were collected from 26 sites in New Zealand that ranged in soil moisture deficits (SMD) from 149 days per year (very dry) to 0 (wet). Rhizobium leguminosarum bv. trifolii populations were quantified (most probable number; MPN) in the field-fresh and dried (48 h forced air) samples from each site, and the percentage population survival determined. Rhizobium leguminosarum bv. trifolii survival after soil drying was strongly correlated to SMD (P < 0.001; R2 = 0.42), providing evidence for strong selection for desiccation tolerant phenotypes in dry environments. Desiccation tolerance of R. leguminosarum bv. trifolii isolated from nodules taken from white clover plants grown in fresh and dried soils from three sites was compared in a micro-droplet assay. Strains from plants grown in the dried soils were more tolerant to rapid drying under in vitro conditions (P < 0.001). Screening of a subset of strains on a range of osmolytes (phenotype microarray), showed desiccation tolerance was associated with tolerance to the salts sodium nitrite, sodium nitrate, and ammonium sulphate, and ethylene glycol. Growth in the presence of ethylene glycol maybe useful surrogate indicators of desiccation tolerance in R. leguminosarum bv. trifolii. Overall, these results show that environmental conditions can provide a basis for selection of populations with desiccation tolerance, and plant-based baiting can be used to recover strains with improved characteristics.

Published
2016

7. State of the Climate in 2013

Author

Olga Clorinda Penalba, David A. Robinson, Steve Ready, Edward Hanna, Philip J. Klotzbach, Christopher W. Landsea, Hugo G. Hidalgo, Ursula Schauer, H. Loeng, Martin O. Jeffries, Jacqueline M. Spence, Christopher S. Meinen, Garret G. Campbell, Qiuhong Tang, Muyin Wang, Hongxing Liu, R. Yamada, Gloria L. Manney, Nicolas Fauchereau, Xavier Fettweis, Ricardo M. Trigo, S Barreira, Norman G. Loeb, Tuomas Laurila, Uwe Send, Eduardo Zambrano, Alexander Baklanov, Diego Loyola, Eleanor Frajka-Williams, Ahira Sánchez-Lugo, Kaarle Kupiainen, Gabriel J. Wolken, H. Kheyrollah Pour, John Kennedy, Simon McGree, Nicolai I. Shiklomanov, Alberto Setzer, Vernie Marcellin-Honore’, Adelina Albanil, Jack Kohler, Patricia K. Quinn, Edward J. Dlugokencky, N. G. Oberman, L. Chang’a, Laurence C. Smith, David Burgess, Peter Schlosser, Jochem Marotzke, Eric S. Blake, Shujie Wang, Arne Dahlback, Shotaro Tanaka, Vladimir E. Romanovsky, David A. Siegel, Agnes Kijazi, P. Sawaengphokhai, Lori Bruhwiler, Jeremy T. Mathis, Jason E. Box, R. B. Ingvaldsen, Stacey M. Frith, Stanley B. Goldenberg, Michele L. Newlin, Igor V. Polyakov, Kyun Kuk Kang, Robert Whitewood, Suzana J. Camargo, John A. Augustine, Natalya Kramarova, James W. Elkins, Michael S. Halpert, Zeng-Zhen Hu, M. C. Gregg, James S. Famiglietti, Johannes W. Kaiser, Mary-Louise Timmermans, William E. Johns, Melanie Coldewey-Egbers, Chris K. Folland, Shaun Quegan, Kazuyoshi Yoshimatsu, Marcel Nicolaus, Michael Kendon, Steven A. Ackerman, Gerard McCarthy, Peter Ambenje, Ivan E. Frolov, Laban Ogallo, Juan Bazo, Jonathan Gottschalck, Kaisa Lakkala, Alexandre M. Ramos, Arun Kumar, Serhat Sensoy, Russell S. Vose, Matthias Lankhorst, Isabelle Tobin, Allen Pope, Hyuanjun Kim, Nadine Gobron, R. Pascual, Samuel Remy, Chris Fenimore, Wassila M. Thiaw, Sharon L. Smith, Samar Khatiwala, Linda M. Keller, Jnes Uwe Grooß, Shashi K. Gupta, Fatemeh Rahimzadeh, Benjamin Rabe, Jacqueline A. Richter-Menge, Mauri Pelto, K. S. Law, Lisan Yu, Catia M. Domingues, Kathleen Dohan, Jake Crouch, Taro Takahashi, Robert Vautard, Germar Bernhard, Don P. Chambers, P. Luhunga, Song Shu, T. S. Jensen, Ryan L. Fogt, Silvia L. Garzoli, T. Kikuchi, Robert Dunn, José Luis Stella, H. Ng’ongolo, Joshua K. Willis, Andreas Herber, Gualberto Carrasco, Geoff S. Dutton, Yan Xue, Kyle Hilburn, Laura C. Brown, Gustavo J. Goni, Paul A. Newman, Ricardo A. Locarnini, E. Hyung Park, Mario Bidegain, Chris T. Fogarty, Jorge A. Amador, Hiroshi Ohno, David E. Parker, I. Hanssen-Bauer, Johannes Flemming, J. V. Revadekar, Michael C. Pitts, Alexandre Bernardes Pezza, Chunzai Wang, Bryan A. Franz, Jared Rennie, Scott J. Weaver, Thomas M. Smith, Stuart A. Cunningham, K. von Salzen, Shigeto Nishino, Stephen Baxter, Rene Lobato, David P. Kratz, I. A. James, Zo Rakotomavo, Peter Thorne, Kathleen L. McInnes, Phillipe Ciais, Von P. Walden, Martin Stengel, Geir O. Braathen, J. L. Vazquez, Angela Benedetti, Daniel Chung, Todd B. Kimberlain, Lincoln M. Alves, Christopher J. Cox, Mark Flanner, Jae Schemm, Peiqun Zhang, Eric J. Alfaro, Dmitry A. Streletskiy, John Cappelen, Yinghui Liu, Terry Haran, Natalia N. Korshunova, Jessica N. Cross, Idelmis T. Gonzalez, Uma S. Bhatt, Tannecia S. Stephenson, Nick Rayner, Shenfu Dong, Takmeng Wong, Xungang Yin, Ingrid L. Rivera, Seong-Joong Kim, David A. Smeed, Peter Bissolli, Mary Butler, Maurizio Santoro, Jerry Ziemke, Will Hobbs, Jeffrey R. Key, P. Jeremy Werdell, Bryan J. Johnson, Wiley Evans, Lamjav Oyunjargal, Liang Peng, Arlene P. Aaron-Morrison, John J. Marra, Avalon O. Porter, Juan Arévalo, Andries Kruger, Blanca Calderón, Phillip Reid, James A. Renwick, Stefan Hendricks, Christoph Reimer, Gregory C. Johnson, Gary T. Mitchum, Torsten Kanzow, John Wahr, K. Alama Coulibaly, G. V. Malkova, David H. Bromwich, Michael A. Taylor, Shu Oeng Ben Ho, Christian Euscátegui, Rick Lumpkin, Matthew A. Lazzara, Michael J. Behrenfeld, Kyle R. Clem, Ross Brown, Michael J. Foster, Juan José Nieto, Robert A. Massom, Blair Trewin, John I. Antonov, Mark A. Merrifield, Christoph Paulik, Guido R. van der Werf, Robert Parinussa, Mark A. Lander, Mark Weber, Diana Hovhannisyan, Rochard A.M. de Jeu, Jennifer A. Francis, L. M. Andreassen, Anthony Arendt, Rik Wanninkhof, Sebastian Hahn, Walter N. Meier, Gustavo Goni, Vyacheslav N. Razuvaev, Robert S. Pickart, John R. Christy, Xiangze Jin, José A. Marengo, Awatif Ebrahim, Eric R. Nash, Rolf Müller, Donald K. Perovich, Chris Derksen, H. K. Ha, Ben Hamlington, L. Jones, Junhong Wang, Guillaume Jumaux, Denis Volkov, I-I Lin, Christopher S. Oludhe, Asa K. Rennermalm, Caio A. S. Coelho, Stephen A. Montzka, Vladimir Sokolov, Rebecca A. Woodgate, Paul Berrisford, Ted Scambos, John Walsh, Michiyo Yamamoto-Kawai, Andrew K. Heidinger, Tim R. McVicar, Shih-Yu Wang, Amal Sayouri, S. J. Vavrus, Jing-Jia Luo, Philip R. Thompson, Katja Trachte, James Reagan, Olga N. Bulygina, Wolfgang Wagner, Mark Tschudi, Derek S. Arndt, Zachary Atheru, Sangeeta Sharma, Christopher L. Sabine, John M. Lyman, David Phillips, Carl Mears, Richard A. Krishfield, Ana María Durán-Quesada, Darren Rayner, Molly O. Baringer, Fatou Sima, Jhan Carlo Espinoza, Taikan Oki, James E. Overland, Sharon Stammerjohn, Hsun Ying Kao, Gerald D. Bell, Bjørn Helge Johnsen, Bin Wang, Thomas E. Evans, William J. Williams, Jan L. Lieser, John A. Knaff, B. M. Kim, Tapani Koskela, Antje Inness, Andre Obregon, Alexander Kholodov, Carla Vega, Andreas Becker, B. C. Maddux, Andrew Lorrey, Khadija Kabidi, Pamela Levira, Helga Nitsche, M. L. Geai, Igor Ashik, S. Zimmerman, Charles Chip Guard, J A Ronald van der, Lin Zhao, Petra R. Chappell, Timothy P. Boyer, Dmitry Drozdov, Bert Wouters, Jayaka D. Campbell, Francis S. Dekaa, W. M. Smethie, Viva Banzon, R. Steven Nerem, Rob Allan, Craig S. Long, R. Martinez, Sergei Marchenko, Wolfgang Steinbrecht, Karin Gleason, Robert S. Stone, Lei Wang, A. Brett Mullan, Skie Tobin, Jeannette Noetzli, Doug Worthy, Vigdis Vestreng, Michelle L. Santee, Kate M. Willett, Nathan Bindoff, Michael Steele, Karen H. Rosenlof, Anu Heikkilä, Claude R. Duguay, Josyane Ronchail, Anne C. Wilber, A. Johannes Dolman, A. K. Srivastava, Andreas Stohl, M. Rajeevan, R. S. W. van de Wal, Catherine Ganter, Markus G. Donat, Adrian R. Trotman, Lucie A. Vincent, Carl J. Schreck, Richard A. Feely, Y. Y. Liu, Michelle L’Heureux, Kari Luojus, Mauro Gugliemin, Charlotte McBride, Howard J. Diamond, David Barriopedro, Rosalind C. Blenman, Tove Marit Svendby, Jessica Blunden, Sebastian Gerland, Paul W. Stackhouse, Simon A. Good, Guojie Wang, Richard J. Pasch, Julia Schmale, Glenroy Brown, B. D. Hall, Sean M. Davis, Mahbobeh Khoshkam, John M. Toole, Claudia Schmid, Bernard Pinty, Wilson Gitau, Leif G. Anderson, Matthew Rodell, Kathy Lantz, Dale F. Hurst, Hanne H. Christiansen, Thomas L. Mote, Owen R. Cooper, Richard R. Heim, William Sweet, Eric Leuliette, G. S.E. Lagerloef, Gregor Macara, Marco Tedesco, Vitali Fioletov, T. W. Kim, Melisa Menendez, Natalie McLean, J. D. Wild, Steve Colwell, Michael C. Kruk, Martin Sharp, J.-J. Morcrette, Jens Mühle, and Wouter Dorigo

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, Download, 010502 geochemistry & geophysics, 01 natural sciences, Geography, 13. Climate action, Synoptic scale meteorology, F860 Climatology, Data_FILES, 14. Life underwater, State (computer science), 0105 earth and related environmental sciences
Abstract

In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events. According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earths surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range. In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new daily maximum sea ice area of 19.57 million km2 reached on 1 October. ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming. Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970. In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost. At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series. © 2014, American Meteorological Society. All rights reserved.

Published
2014

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