STATE OF THE CLIMATE IN 2011 Special Supplement to the Bulletin of the American Meteorological Society Vol. 93, No. 7, July 2012

Jean-Francois Cretaux (1) , William Sweet (2) , Jake Crouch , Taro Takahashi (3) , Stuart A. Cunningham , Michael A. Taylor , Richard A. M. de Jeu (4) , Marco Tedesco , M. Demircan , Jean-Noel Thepaut (5) , C. Derksen (6) , Wassila M. Thiaw , Howard J. Diamond , Philip Thompson , Ed J. Dlugokencky (2) , Peter W. Thorne , Kathleen Dohan (7) , M. L. Timmermans , A. Johannes Dolman (8) , Skie Tobin , Wouter A. Dorigo (9) , J. Toole , D. S. Drozdov , Katja Trachte , Claude Duguay , Blair C. Trewin , Ellsworth Dutton , Ricardo M. Trigo (10) , Geoff S. Dutton (11, 12) , Adrian Trotman , James W. Elkins (11) , C. J. Tucker , H. E. Epstein , Yusuf Ulupinar , James S. Famiglietti (13, 14, 15) , Roderik S. W. van De Wal , Odile Hembise Fanton d'Andon , G. R. van Der Werf , Richard A. Feely (16) , Robert Vautard (17, 18) , Balazs M. Fekete , Gary Votaw , Chris Fenimore , Wolfgang W. Wagner , D. Fernandez-Prieto , John Wahr (19) , Erik Fields , D. A. Walker , Vitali Fioletov (20) , J. Walsh (21) , Ryan L. Fogt , Chunzai Wang (22) , Chris Folland , Junhong Wang (23) , Michael J. Foster (24) , Lei Wang (25) , Eleanor Frajka-Williams (26) , Menghua Wang (27) , Bryan A. Franz , Sheng-Hung Wang , Karen Frey , Rik H. Wanninkhof (22) , Stacey H. Frith , Scott Weaver (28) , I. Frolov , Mark Weber (29) , G. V. Frost , T. Weingartner , Catherine Ganter , Robert A. Weller , Silvia Garzoli (22) , Frank Wentz , Wilson Gitau (30, 31) , Robert Whitewood , Karin L. Gleason , Anne C. Wilber , Nadine Gobron (32) , Kate M. Willett (33) , Stanley B. Goldenberg , W. Williams , Gustavo Goni (2) , Joshua K. Willis , Idelmis Gonzalez-Garcia , R. Chris Wilson , Nivaldo Gonzalez-Rodriguez , G. Wolken , Simon A. Good , Takmeng Wong , Philippe Goryl , R. Woodgate , Jonathan Gottschalck , Alex J. Wovrosh , C. M. Gouveia , Yan Xue (34) , Margarita C. Gregg , Ryuji Yamada , Georgina M. Griffiths , M. Yamamoto-Kawai , Valentina Grigoryan , James A. Yoder , Jens-Uwe Grooss , Lisan Yu (35) , Chip Guard , Simon Yueh (14) , Mauro Guglielmin (36) , Liangying Zhang , Bradley D. Hall (11) , Peiqun Zhang , Michael S. Halpert , Lin Zhao (37) , Andrew K. Heidinger (27) , Xinjia Zhou , Anu Heikkila (38) , S. Zimmerman , Richard R. Heim , Lafeer Zubair , Paula A. Hennon , Hugo G. Hidalgo (39) , Kyle Hilburn , Shu-Peng Ho (40, 41) , Will R. Hobbs , Simon Holgate , Simon J. Hook (14) , Anahit Hovsepyan , Zeng-Zhen Hu , Sebastien Hugony , Dale F. Hurst (42) , R. Ingvaldsen , M. Itoh (43) , Ena Jaimes , Martin Jeffries , William E. Johns (44) , Bjorn Johnsen (45) , Bryan Johnson (11) , Gregory C. Johnson , L. T. Jones , Guillaume Jumaux (46) , Khadija Kabidi , Johannes W. Kaiser (5) , Kyun-Kuk Kang , Torsten O. Kanzow , Hsun-Ying Kao (7) , Linda M. Keller , Mike Kendon , John J. Kennedy , Sefer Kervankiran , J. Key , Samar Khatiwala (47) , A. L. Kholodov , M. Khoshkam , T. Kikuchi , Todd B. Kimberlain , Darren King , John A. Knaff , Natalia N. Korshunova , Tapani Koskela , David P. Kratz (48) , R. Krishfield , Andries Kruger , Michael C. Kruk , Arun Kumar (49) , Gary Lagerloef (50) , Kaisa Lakkala (38) , Richard B. Lammers , Mark A. Lander , Chris W. Landsea , Matthias Lankhorst (51, 52) , Braulio Lapinel-Pedroso , Matthew A. Lazzara , Sharon Leduc , Penehuro Lefale , Gloria Leon , Antonia Leon-Lee , Eric Leuliette (41) , Syndney Levitus , Michelle L'Heureux , I. I. Lin , Hongxing Liu , Yanju Liu , Yi Liu (53, 54) , Rene Lobato-Sanchez , Ricardo Locarnini , Norman G. Loeb (48) , H. Loeng , Craig S. Long (55) , Andrew M. Lorrey , Rick Lumpkin (56) , Cathrine Lund Myhre (57) , Jing-Jia Luo (58) , John M. Lyman , Stuart Maccallum , Alison M. Macdonald , Brent C. Maddux , Gloria Manney (59, 60) , S. S. Marchenko , Jose A. Marengo , Stephane Maritorena , Jochem Marotzke (61) , John J. Marra , Odayls Martinez-Sanchez , J. Maslanik , Robert A. Massom (62, 63) , Jeremy T. Mathis (16) , Charlotte Mcbride , Charles R. Mcclain , Daniel Mcgrath (64) , Simon Mcgree , F. Mclaughlin , Tim R. Mcvicar (65, 66) , Carl Mears (67) , W. Meier , Christopher S. Meinen , Melisa Menendez (68, 69) , Chris Merchant , Mark A. Merrifield , Laury Miller , Gary T. Mitchum , Stephen A. Montzka (11) , Sue Moore (70) , Natalie P. Mora , Jean-Jacques Morcrette (5) , Thomas Mote , Jens Muhle (71) , A. Brett Mullan , Rolf Muller (72) , Cathrine Myhre , Eric R. Nash , R. Steven Nerem , Michele L. Newlin , Paul A. Newman (73) , Arona Ngari , S. Nishino , Lenoard N. Njau , Jeannette Noetzli (74) , N. G. Oberman , Andre Obregon , Laban Ogallo (31) , Christopher Oludhe , J. Overland , Lamjav Oyunjargal , R. M. Parinussa , Geun-Ha Park (75) , David E. Parker , Richard J. Pasch , Reynaldo Pascual-Ramirez , Mauri S. Pelto (76) , Olga Penalba , Ramon Perez-Suarez , D. Perovich (77) , Alexandre B. Pezza , Dave Phillips , R. Pickart , C. Achberger , Bernard Pinty (78) , S. A. Ackerman (79) , J. Pinzon (73) , Farid H. Ahmed , Michael C. Pitts , Adelina Albanil-Encarnacion , Homa Kheyrollah Pour , E. J. Alfaro , John Prior (80) , L. M. Alves (81) , Jeff L. Privette , Rob Allan , A. Proshutinsky , Jorge A. Amador , Shaun Quegan (82) , Peter Ambenje , Juan Quintana (83) , David Antoine (84) , B. Rabe , John Antonov , Fatemeh Rahimzadeh , Juan Arevalo , M. Rajeevan (85, 86) , Derek S. Arndt , Darren Rayner , I. Ashik , Nick A. Rayner , Zachary Atheru , M. K. Raynolds , Alessandro Baccini (87, 88) , Vyacheslav N. Razuvaev , Julian Baez , James Reagan , Viva Banzon , Phillip Reid (89) , Molly O. Baringer (2) , James A. Renwick , Sandra Barreira , J. Revadekar , D. E. Barriopedro , Markus Rex (90) , J. J. Bates , J. Richter-Menge , Andreas Becker (91) , Ingrid L. Rivera , Michael J. Behrenfeld (92) , David A. Robinson (93) , Gerald D. Bell , Matthew Rodell (73) , Angela Benedetti (5) , Michael L. Roderick , Germar Bernhard (94) , Vladimir E. Romanovsky , Paul Berrisford , Josyane Ronchail (95, 96) , David I. Berry (26) , Karen H. Rosenlof (11) , A. Beszczynska-Moeller , B. Rudels (38) , U. S. Bhatt , Christopher L. Sabine (16) , Mario Bidegain (97) , Ahira Sanchez-Lugo (27) , P. Bieniek , Michelle L. Santee (14) , Charon Birkett , P. Sawaengphokhai (98) , Peter Bissolli , Amal Sayouri , Eric S. Blake , Ted A. Scambos (99) , Jessica Blunden , U. Schauer (90, 100) , Dagne Boudet-Rouco , Jae Schemm , Jason E. Box , Claudia Schmid , Tim Boyer , Carl Schreck (101) , Geir O. Braathen , Igor Semiletov , G. Robert Brackenridge , Uwe Send (52) , Philip Brohan , Serhat Sensoy , David H. Bromwich , Natalia Shakhova , Laura Brown , M. Sharp (102) , R. Brown (103) , Nicolai I. Shiklomanov , Lori Bruhwiler (2) , K. Shimada (104) , O. N. Bulygina , J. Shin (105, 106) , John Burrows (107) , David A. Siegel , Blanca Calderon , Adrian Simmons (5) , Suzana J. Camargo , Maria Skansi , John Cappellen , Thomas M. Smith , E. Carmack , V. Sokolov , Gualberto Carrasco , Jacqueline Spence , Don P. Chambers , A. K. Srivastava , Hanne H. Christiansen (108) , Paul W. Stackhouse , John Christy , Sharon Stammerjohn (109) , D. Chung , M. Steele , P. Ciais (17) , Konrad Steffen (110) , Caio A. S. Coehlo , Wolfgang Steinbrecht (111) , Steve Colwell (112) , Tannecia Stephenson , J. Comiso , Richard S. Stolarski

1 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
2 NOAA - National Oceanic and Atmospheric Administration
3 LDEO - Lamont-Doherty Earth Observatory
4 Space Technology Center
5 ECMWF - European Centre for Medium-Range Weather Forecasts
6 Climate Research Division [Toronto]
7 ESR - Earth and Space Research Institute [Seattle]
8 Department of Hydrology and Geo-Environmental Sciences [Amsterdam]
9 TU Wien - Vienna University of Technology
10 Instituto Dom Luiz
11 ESRL - NOAA Earth System Research Laboratory
12 CIRES - Cooperative Institute for Research in Environmental Sciences
13 ESS - Department of Earth System Science [Irvine]
14 JPL - Jet Propulsion Laboratory
15 UCCHM - University of California Center for Hydrologic Modeling [Irvine]
16 PMEL - NOAA Pacific Marine Environmental Laboratory [Seattle]
17 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
18 ESTIMR - Extrèmes : Statistiques, Impacts et Régionalisation
19 Department of Physics [Boulder]
20 Environment and Climate Change Canada
21 INFN - Istituto Nazionale di Fisica Nucleare [Pisa]
22 AOML - NOAA Atlantic Oceanographic and Meteorological Laboratory
23 University at Albany [SUNY]
24 CIMSS - Cooperative Institute for Meteorological Satellite Studies
25 Peking University [Beijing]
26 NOC - National Oceanography Centre [Southampton]
27 NESDIS - NOAA National Environmental Satellite, Data, and Information Service
28 UTMB - The University of Texas Medical Branch
29 IUP - Institut für Umweltphysik [Bremen]
30 Department of Meteorology
31 ICPAC - Climate Prediction and Applications Centre
32 Institute for Environment and Sustainability of the JRC
33 MOHC - Met Office Hadley Centre for Climate Change
34 AII - Agricultural Information Institute
35 WHOI - Woods Hole Oceanographic Institution
36 Uninsubria - Universitá degli Studi dell’Insubria = University of Insubria [Varese]
37 Heilongjiang Institute of Science and Technology
38 FMI - Finnish Meteorological Institute
39 UCR - Universidad de Costa Rica
40 UCAR - University Corporation for Atmospheric Research
41 STAR - NOAA Center for Satellite Applications and Research
42 GML - ESRL Global Monitoring Laboratory [Boulder]
43 Materials and structures Laboratory
44 RSMAS - Rosenstiel School of Marine and Atmospheric Science
45 Norwegian Radiation and Nuclear Safety Authority
46 DIROI - Direction Interrégionale de Météo-France pour l'océan Indien
47 Department of Earth Sciences [Oxford]
48 LaRC - NASA Langley Research Center [Hampton]
49 UHM - University of Hawai‘i [Mānoa]
50 Department of Earth and Space Sciences [Seattle]
51 IFM-GEOMAR - Leibniz-Institut für Meereswissenschaften
52 SIO - UC San Diego - Scripps Institution of Oceanography
53 Agroécologie [Dijon]
54 HZAU - Huazhong Agricultural University [Wuhan]
55 NWS - NOAA National Weather Service
56 Department of Oceanography
57 NILU - Norwegian Institute for Air Research
58 RIGC - Research Institute for Global Change
59 NWRA - NorthWest Research Associates
60 Department of Physics [Socorro]
61 Ocean and Earth Science [Southampton]
62 AAD - Australian Antarctic Division
63 ACE-CRC - Antarctic Climate and Ecosystems Cooperative Research Centre
64 Massachusetts General Hospital [Boston]
65 CSIRO - Commonwealth Scientific and Industrial Research Organisation [Canberra]
66 ARC - Australian Research Council
67 RSS - Remote Sensing Systems [Santa Rosa]
68 DIAL - Développement, institutions et analyses de long terme
69 Université Paris Dauphine-PSL
70 NMFS - NOAA National Marine Fisheries Service
71 UC San Diego - University of California [San Diego]
72 NMR and Molecular Imaging Laboratory [Mons]
73 GSFC - NASA Goddard Space Flight Center
74 Glaciology, Geomorphodynamics and Geochronology
75 Chemistry Department [Massachusetts Institute of Technology]
76 Nichols College Dudley
77 CRREL - ERDC Cold Regions Research and Engineering Laboratory
78 European Commission
79 SSEC - Space Science and Engineering Center [Madison]
80 Lausanne University Hospital
81 Centro de Ciencias do Sistema Terrestre
82 University of Sheffield
83 Hochschule Mannheim - University of Applied Sciences
84 LOV - Laboratoire d'océanographie de Villefranche
85 IITM - Indian Institute of Tropical Meteorology
86 Ministry of Earth Sciences [India]
87 Woods Hole Research Center
88 Department of Earth and Environment [Boston]
89 CAWCR - Centre for Australian Weather and Climate Research
90 AWI - Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
91 Génétique et Ecologie des Virus, Génétique des Virus et Pathogénèse des Maladies Virales
92 Department of Botany and Plant Pathology
93 Ctr Ecol & Hydrol, Bangor
94 Biospherical Instruments Inc.
95 PARVATI - Processus de la variabilité climatique tropicale et impacts
96 UPD7 - Université Paris Diderot - Paris 7
97 Instituto Uruguayo de Meteorología, Javier Barrios Amorín 1488, CP 11200, Montevideo, Uruguay
98 SSAI - Science Systems and Applications, Inc. [Hampton]
99 NSIDC - National Snow and Ice Data Center
100 NPS - Naval Postgraduate School
101 UC Berkeley - University of California [Berkeley]
102 ERDC - USACE Engineer Research and Development Center
103 CPMOH - Centre de physique moléculaire optique et hertzienne
104 CYRIC
105 The University of Tennessee [Knoxville]
106 ORNL - Oak Ridge National Laboratory [Oak Ridge]
107 Universität Bremen
108 UNIS - The University Centre in Svalbard
109 INSTAAR - Institute of Arctic Alpine Research [University of Colorado Boulder]
110 Swiss Federal Institute for Forest, Snow and Landscape Research WSL
111 MOHp - Meteorologisches Observatorium Hohenpeißenberg
112 BAS - British Antarctic Survey

Large-scale climate patterns influenced temperature and weather patterns around the globe in 2011. In particular, a moderate-to-strong La Nina at the beginning of the year dissipated during boreal spring but reemerged during fall. The phenomenon contributed to historical droughts in East Africa, the southern United States, and northern Mexico, as well the wettest two-year period (2010-11) on record for Australia, particularly remarkable as this follows a decade-long dry period. Precipitation patterns in South America were also influenced by La Nina. Heavy rain in Rio de Janeiro in January triggered the country's worst floods and landslides in Brazil's history. The 2011 combined average temperature across global land and ocean surfaces was the coolest since 2008, but was also among the 15 warmest years on record and above the 1981-2010 average. The global sea surface temperature cooled by 0.1 degrees C from 2010 to 2011, associated with cooling influences of La Nina. Global integrals of upper ocean heat content for 2011 were higher than for all prior years, demonstrating the Earth's dominant role of the oceans in the Earth's energy budget. In the upper atmosphere, tropical stratospheric temperatures were anomalously warm, while polar temperatures were anomalously cold. This led to large springtime stratospheric ozone reductions in polar latitudes in both hemispheres. Ozone concentrations in the Arctic stratosphere during March were the lowest for that period since satellite records began in 1979. An extensive, deep, and persistent ozone hole over the Antarctic in September indicates that the recovery to pre-1980 conditions is proceeding very slowly. Atmospheric carbon dioxide concentrations increased by 2.10 ppm in 2011, and exceeded 390 ppm for the first time since instrumental records began. Other greenhouse gases also continued to rise in concentration and the combined effect now represents a 30% increase in radiative forcing over a 1990 baseline. Most ozone depleting substances continued to fall. The global net ocean carbon dioxide uptake for the 2010 transition period from El Nino to La Nina, the most recent period for which analyzed data are available, was estimated to be 1.30 Pg C yr(-1), almost 12% below the 29-year long-term average. Relative to the long-term trend, global sea level dropped noticeably in mid-2010 and reached a local minimum in 2011. The drop has been linked to the La Nina conditions that prevailed throughout much of 2010-11. Global sea level increased sharply during the second half of 2011. Global tropical cyclone activity during 2011 was well-below average, with a total of 74 storms compared with the 1981-2010 average of 89. Similar to 2010, the North Atlantic was the only basin that experienced above-normal activity. For the first year since the widespread introduction of the Dvorak intensity-estimation method in the 1980s, only three tropical cyclones reached Category 5 intensity level-all in the Northwest Pacific basin. The Arctic continued to warm at about twice the rate compared with lower latitudes. Below-normal summer snowfall, a decreasing trend in surface albedo, and above-average surface and upper air temperatures resulted in a continued pattern of extreme surface melting, and net snow and ice loss on the Greenland ice sheet. Warmer-than-normal temperatures over the Eurasian Arctic in spring resulted in a new record-low June snow cover extent and spring snow cover duration in this region. In the Canadian Arctic, the mass loss from glaciers and ice caps was the greatest since GRACE measurements began in 2002, continuing a negative trend that began in 1987. New record high temperatures occurred at 20 m below the land surface at all permafrost observatories on the North Slope of Alaska, where measurements began in the late 1970s. Arctic sea ice extent in September 2011 was the second-lowest on record, while the extent of old ice (four and five years) reached a new record minimum that was just 19% of normal. On the opposite pole, austral winter and spring temperatures were more than 3 degrees C above normal over much of the Antarctic continent. However, winter temperatures were below normal in the northern Antarctic Peninsula, which continued the downward trend there during the last 15 years. In summer, an all-time record high temperature of -12.3 degrees C was set at the South Pole station on 25 December, exceeding the previous record by more than a full degree. Antarctic sea ice extent anomalies increased steadily through much of the year, from briefly setting a record low in April, to well above average in December. The latter trend reflects the dispersive effects of low pressure on sea ice and the generally cool conditions around the Antarctic perimeter.

Domains: Sciences of the Universe [physics]; Earth Sciences; Oceanography

Jean-Francois Cretaux, William Sweet, Jake Crouch, Taro Takahashi, Stuart A. Cunningham, et al.. STATE OF THE CLIMATE IN 2011 Special Supplement to the Bulletin of the American Meteorological Society Vol. 93, No. 7, July 2012. Bulletin of the American Meteorological Society, 2012, 93 (7, S), pp.S1-S263. ⟨10.1175/2012BAMSStateoftheClimate.1⟩. ⟨hal-03502662⟩