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WMO statement on the status of the global climate in 2014WMO-No. 1152WMO, in collaboration with Members, began issuing annual statements on the status of the global climate in 1993. This publication was issued in collaboration with the Met Office Hadley Centre, United Kingdom of Great Britain and Northern Ireland; the Climatic Research Unit CRU at the University of East Anglia, United Kingdom; the Climate Prediction Center CPC, the National Climatic Data Center NCDC, the National Oceanographic Data Center NODC and the National Hurricane Center NHC of the National Oceanic and Atmospheric Administration NOAA, United States of America; the Goddard Institute for Space Studies GISS operated by the National Aeronautics and Space Administration NASA, United States; the Japan Meteorological Agency JMA, Japan; the European Centre for Medium-Range Weather Forecasts ECMWF, United Kingdom; the Global Precipitation Climatology Centre GPCC, Germany; the National Snow and Ice Data Center NSIDC, United States; the Commonwealth Scientific and Industrial Research Organization CSIRO Marine and Atmospheric Research, Australia; and the Global Snow Lab, Rutgers University, United States. Other contributors are the National Meteorological and Hydrological Services or equivalent climate institutions of Argentina, Armenia, Australia, Austria, Bangladesh, Belarus, Bosnia and Herzegovina, Brazil, Bulgaria, Canada, China, Croatia, Cyprus, Czech Republic, Denmark, Fiji, Finland, France, Gambia the, Germany, India, Iran Islamic Republic of, Ireland, Israel, Italy, Japan, Kenya, Luxembourg, Mauritius, Mexico, Morocco, Mozambique, New Zealand, Norway, Pakistan, Poland, Portugal, Republic of Korea, Russian Federation, Serbia, Slovakia, South Africa, Spain, Sri Lanka, Sweden, Switzerland, Tunisia, Turkey, United Kingdom, United Republic of Tanzania, and United States. The WMO Regional Association VI Europe Regional Climate Centre on Climate Monitoring; the African Centre of Meteorological Applications for Development ACMAD, Niamey; the Hong Kong Observatory, Hong Kong, China; the International Research Centre on El Niño CIIFEN, Guayaquil, Ecuador; the University of Washington Polar Science Center, United States; and the Royal Netherlands Meteorological Institute KNMI, Netherlands, also contributed.WMO-No. 1152© World Meteorological Organization, 2015The right of publication in print, electronic and any other and in any language is reserved by WMO. Short extracts from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated. Editorial correspondence and requests to publish, reproduce or translate this publication in part or in whole should be addressed toChairperson, Publications BoardWorld Meteorological Organization WMO7 bis, avenue de la Paix Tel. 41 0 22 730 84 03P.O. Box 2300 Fax 41 0 22 730 80 40CH-1211 Geneva 2, Switzerland E-mail publicationswmo.intISBN 978-92-63-11152-4NOTEThe designations employed in WMO publications and the presentation of material in this publication do not imply the expression of any opinion what-soever on the part of WMO concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries.The mention of specific companies or products does not imply that they are endorsed or recommended by WMO in preference to others of a similar nature which are not mentioned or advertised.The findings, interpretations and conclusions expressed in WMO publications with named authors are those of the authors alone and do not neces-sarily reflect those of WMO or its Members.Cover illustration Vanessa Vick World Food ProgrammeContentsForeword 3Key findings 4Temperatures 4Rain, snow and ice 5Oceans 7Regional analysis 7Africa 7Asia 8South America 9North America, Central America and the Caribbean 9South-West Pacific 13Europe 13Tropical cyclones 14Greenhouse gases and ozone-depleting substances 15Major weather and climate events around the world in 2014 17Event attribution an application to the global and United Kingdom record temperatures of 2014 183ForewordThe warming trend observed over the past few decades continued in 2014, which WMO has ranked as nominally the warmest year since modern instrumental measurements began in the mid-1800s Although 2014 broke the record by only a few hundredths of a degree – less than the margin of uncertainty – this result means that 14 of the 15 hottest years on record occurred during the twenty-first century The evidence for human-induced global warming is therefore increasingly robust Although discussions of climate change focus primarily on atmospheric warming near the Earth’s surface – which is, of course, where we live our lives – the warming of the ocean is also critically important This is because the ocean absorbs over 93 per cent of the excess heat trapped by rising atmospheric concentrations of greenhouse gases The WMO Statement on the Status of the Global Climate in 2014 reports that global-average sea-surface temperatures for 2014 were warmer than for any previous year on record We need to maintain and even strengthen our ocean observing systems in order to better understand sea-temperature trends and their implications for long-term climate change This Statement also highlights extremes that occurred in 2014 at the national and regional levels Europe, for example, was unusually warm, with 19 countries reporting record tem-peratures for the year Severe flooding and flash floods occurred in many countries, particularly in the Balkans, South Asia, and parts of Africa and South and Central America Natural climate variability creates such extremes every year, but the high incidence of flooding around the world is consistent with an acceler-ated hydrological cycle driven by the additional energy captured in the atmosphere by green-house gases As a result of improved scientific understanding and modelling techniques, good progress has been made on attributing certain observed climate extremes and weather events to human-induced climate change WMO is working with its Members and leading scientific organizations to further advance attribution research with a view to incorporating it into operational climate services in the near future Despite expectations that an El Niño could develop, the event did not materialize, making 2014 a neutral El Niño–Southern Oscillation ENSO year El Niño is typically associated with elevated global temperatures Not only does this mean that 2014 was exceptionally warm despite not being an El Niño year, but the failure of ENSO to mature poses important scientific questions demanding further research Another interesting phenomenon in 2014 was the behaviour of the seas around Antarctica While parts of Antarctica’s land-based glaciers are melting, the sea ice expanded to a record extent for the third year in a row Again, this is an exciting and important area for continued observation and research This Statement draws on data provided by leading global and regional climate centres and research institutes as well as National Meteorological and Hydrological Services It is published in the six official WMO languages in order to reach a broader audience M Jarraud Secretary-General4TEMPERATURESThe global-average near-surface temperature for 2014 was comparable to the warmest years in the 165-year instrumental record In 2014, the global average temperature was 0 57 ± 0 09 °C11 03 ± 0 16 °F above the 1961–1990 average of 14 °C 57 2 °F It was 0 08 °C 0 14 °F above 1The uncertainty is that estimated for the HadCRUT.4.3.0.0 dataset. Estimates produced for the MLOST dataset at ± 0.12 °C are comparable. NASA/GISS does not produce uncertainty estimates for individual years, but the uncertainty of annual averages from 1950–2008 is estimated to be ± 0.05 °C. ftp//ftp.ncdc.noaa.gov/pub/data/mlost/operational/products/aravg.ann.land_ocean.90S.90N.v3.5.4.201409.asc and Hansen et al. 2010.Figure 1. Global annual average temperature anomalies relative to 1961–1990 for 1850–2014. The black line and shaded area which represent the median and 95 uncertainty range respectively are from the HadCRUT.4.3.0.0 dataset produced in collaboration between the Met Office Hadley Centre and the Climatic Research Unit at the University of East Anglia. The blue line is from the GISTEMP analysis produced by the NASA Goddard Institute for Space Studies NASA/GISS. The red line is the Merged Land Ocean Surface Temperature dataset MLOST produced by the NOAA National Climatic Data Center NOAA/NCDC.Source Met Office Hadley Centre, United Kingdom, and Climatic Research Unit, University of East Anglia, United Kingdom1850 1900 1950 2000Year– 0.6– 0.4– 0.200.20.40.6Global average temperature anomaly °CMet Office Hadley Centre and Climatic Research UnitNOAA National Climatic Data CenterNASA Goddard Institute for Space StudiesKey findingsthe average anomaly of 0 50 °C 0 89 °F for the past 10 years 2005–2014 An anomaly of 0 57 ± 0 09 °C 1 03 ± 0 16 °F for the year would nominally place 2014 as the warmest year on record However, the estimated uncertainties in the annual averages are larger than the differences between the warmest years Nominally, the three other warmest years are 2010 0 55 ± 0 09 °C, 2005 0 54 ± 0 09 °C and 1998 0 52 ± 0 09 °C The annual average used by WMO is based on the mean of three global temperature datasets HadCRUT 4 3 0 0 produced by the Met Office Hadley Centre and the Climatic Research Unit at the University of East Anglia in the United Kingdom, MLOST produced by the United States National Oceanic and Atmospheric Administration’s National Climatic Data Center NOAA/NCDC and GISTEMP produced by the United States National Aeronautics and Space Administration’s Goddard Institute for Space Studies NASA/GISS The Japan Meteorological Agency also produces an estimate of the global average temperature, which nominally places 2014 as the warmest year According to data from the reanalysis produced by the European Centre for Medium-Range Weather Forecasts, 2014 was in the top 10 of warmest years since 1979 One of the largest drivers of year-to-year changes in global temperature is the El Niño–Southern KHALEDABDULLAHALIALMAHDIREUTERSA boy pours water over his head from a street tap to cool off in Sana’a, May 2014.5Oscillation ENSO Years that start during an El Niño episode are typically warmer than those that start with neutral ENSO conditions or a La Niña episode Sea-surface temperatures in the eastern tropical Pacific at the end of 2013 were only slightly cooler than average, indicating that the global temperature of 2014 would not be strongly influenced by El Niño or La Niña The average temperature for 2014 was above the long-term mean for most land areas Air tem-peratures averaged over land were 0 88 ± 0 20 °C above the 1961–1990 average according to NOAA estimates, nominally the fourth warmest on record fifth warmest in the CRUTEM4 data-set Areas where the warmth was particularly notable were western North America including Alaska, western Eurasia – many countries in Europe experienced record warmth – eastern Eurasia, much of Africa, large areas of South America, and southern and western Australia Notably cooler-than-average conditions for the year were recorded across large areas of the United States and Canada RAIN, SNOW AND ICEGlobal average precipitation in 2014 was close to the long-term average of 1 033 mm, according to NOAA As usual, the pattern of precipitation anomalies was marked by areas of unusually low and high precipitation Areas of notably low precipitation included particularly the south-west of the United States, north-east China and eastern Brazil, which all experienced drought in 2014 Areas of high annual precipi-tation included the Paraná River basin covering northern Argentina, Bolivia, Paraguay and the south of Brazil, and the Balkans According to data from the Global Snow Lab at Rutgers University in the United States, winter snow cover in the northern hemisphere was above the long-term average Spring snow cover was the third lowest on record since 1966 at close to 28 million km2By contrast, autumn snow cover was the highest on record for the northern hemisphere 22 2 million km2, with a record high autumn extent for North America 9 7 million km2 and the third highest extent for Eurasia 12 5 million km2 Figure 2. Annual average air temperature anomalies over land and sea-surface temperature anomalies over the oceans for 2014 relative to the 1961–1990 average from the HadCRUT.4.3.0.0 dataset. A grid cell average is calculated if there is at least one month of data for at least two quarters. Source Met Office Hadley Centre, United Kingdom, and Climatic Research Unit, University of East Anglia, United KingdomFigure 3. Global annual average temperature anomalies relative to the 1961–1990 average for 1950–2014, based on an average of the three datasets GISTEMP, MLOST and HadCRUT.4.3.0.0. The colouring of the bars indicates whether a year was classified as an El Niño-influenced year red, an ENSO-neutral year grey or a La Niña-influenced year blue.Source Met Office Hadley Centre, United Kingdom, and Climatic Research Unit, University of East Anglia, United Kingdom180 90W 0 90E 18090S60S30S030N60N90N–10 –5 –3 –2 –1 –0.5 0 0.5 123510El Niño Neutral La Niña 1950 1960 1970 1980 1990 2000 2010 Year–0.2 0.0 0.2 0.4 0.6 Temperature anomaly °C6Arctic sea-ice extent2reaches a maximum in March and a minimum in September According to the National Snow and Ice Data Center, in 2014 the annual maximum daily extent, recorded on 21 March, was 14 91 million km2, and the annual minimum daily extent, recorded on 17 September, was 5 02 million km2This daily minimum was the sixth lowest on record The monthly average extent for September was also the sixth lowest on record, 1 24 million km2below 2http//nsidc.org/arcticseaicenews/2014/10/2014-melt-season-in- review/; http//nsidc.org/arcticseaicenews/2014/04/the 1981–2010 average and 1 65 million km2above the record-low extent recorded in September 2012 Antarctic daily sea-ice extent remained at record high levels for much of 2014; a maximum daily extent of 20 11 million km2was reached on 22 September, 0 56 million km2higher than the previous
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