Wmo Statement on the Status of the Global Climate in 2003

WMO STATEMENT ON THE STATUS OF THE GLOBAL CLIMATE IN 2003

2000 ) 2 10 30 2001 Marshall Islands Caroline Islands 2002 Western Eastern Kiribati Line Islands 2003 0 Kiribati Nauru 25 Rawaki Island Papua Solomon Islands New Guinea Tuvalu Tokelau Island Marquesas -10 Islands Samoa Tuamotu Island 20 Vanuatu Fiji Society -20 Niue Islands New Tonga Cook Islands Caledonia Austral Island Pitcaim Island Australia 15 -30

New Area of ozone hole (million km Zealand -40 10 150160 170 180170 160 150 140 130

-1.0-0.5 0.5 1.0 5

For information about WMO, please contact: For more information about the contents of this brochure, please contact: Communications and Public Affairs Office World Climate Programme Department World Meteorological Organization World Meteorological Organization 0 7bis, avenue de la Paix 7bis, avenue de la Paix August September October November December P.O. Box 2300 P.O. Box 2300 CH-1211 Geneva 2, SWITZERLAND CH-1211 Geneva 2, SWITZERLAND Tel: (+41-22) 730 83 14 / 730 83 15 Tel: (+41-22) 730 83 77 Fax: (+41-22) 730 80 27 Fax: (+41-22) 730 80 42 E-mail: [email protected] E-mail: [email protected] Web: http://www.wmo.int Web: http://www.wmo.ch/web/wcp/wcp_prog.htm World Meteorological Organization Weather • Climate • Water WMO-No. 966 2

Front cover: Daily size of the Antarctic ozone hole from 1 August to 30 November for the period 2000-2003. (Source: Ozone data analyses are prepared in collaboration with the WMO World Ozone and Ultraviolet Data Centre in Toronto, Canada through the cooperation and support of the Meteorological Service of Canada)

Back cover: Snow cover anomalies for February 2003 (departures in percentage from the average in the 1988-2002 base period). Snow cover data is derived from visible satellite imagery using the special sensor microwave imager. Together with positive anomalies over Central Asia in December 2002 and over China in January 2003, the February 2003 values contributed to the second highest snow cover during the 2002/2003 winter season since records began in 1967. (Source: National Climatic Data Center, NOAA, USA)

Bottom: Sea-surface temperature anomalies for 2003 (departures in degrees Celsius from the average in the 1982-1996 base period). Lighter and darker red indicate regions with warmer than average sea- surface temperature. (Sources: Bureau of Meteorology, Australia; National Institute of Water and Atmospheric Research, New Zealand; Climate Prediction Center, NOAA, USA)

NOTE The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Meteorological Organization concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries.

This statement is a summary of the information provided by the Hadley Centre of the Met Office, UK, the Climatic Research Unit, University of East Anglia, United Kingdom; and the National Environmental Satellite and Data Information Service and the National Weather Service of the National Oceanic and Atmospheric Administration (NOAA). Other contributors were from the following WMO Member countries and territories: Argentina, Australia, Canada, France, Germany, India, Japan, Mauritius, the Netherlands, New Zealand, World Norway, Spain, Sweden, Switzerland, as well as the International Research Institute for Climate Prediction Meteorological in New York, the Drought Monitoring Centre in Nairobi, the World Glacier Monitoring Service in Zürich, and Organization the AGRHYMET Centre in Niamey. Geneva - Switzerland 3

FOREWORD

Since 1993, the World Meteorological Organization (WMO), to improved protection of life and property. Enhanced through the Commission for Climatology and in coopera- weather, climate and hydrological services are being tion with its Members, has issued annual statements on the implemented to reduce the adverse human, social and status of the global climate. This year’s statement describes economic impacts of natural disasters and of extreme the climatic conditions, including extreme weather events, weather and climate events, through increased awareness for the year 2003 and provides a historical perspective on and preparedness of people and societies to face such some of the variability and trends that have occurred since events. The improved observing systems and active the nineteenth century. The statements complement the climate monitoring and research programmes increas- periodic assessments of the WMO/United Nations ingly support governments and world decision makers in Environment Programme (UNEP) Intergovernmental Panel industry and commerce in deciding on correct responses on Climate Change (IPCC), which provide valuable input to to overcome problems and to exploit advantageous envi- national and international negotiations. ronmental conditions. New scientific and technological The information contained in this statement developments and growing social and economic demands enhances the scientific understanding of the changes in are being focused through stronger cooperation among climate and the associated impacts that have occurred in many disciplines, within and among countries, in order to the past, making it possible to improve on our projections seize the full benefits of weather, climate and water fore- for the future. Through continuing research and the casts and warnings while protecting the environment. collection of consistent and complete observations by WMO will actively contribute to the development of WMO and its Members, progress towards an even better a more integrated approach to global observing based on understanding of the Earth’s climate system is possible. its surface- and space-based networks. The timely provi- The influence of weather and climate on human well sion of authoritative climate statements, climate being, and the inherent impact on the environment, were assessments, climate reviews and descriptions of climate evident during the past year. Tropical cyclones in various variations and their historical perspective will continue its parts of the world caused loss of life and destroyed prop- important role in WMO’s contribution to sustainable erty. Droughts affected the livelihood of many people, and development. heat waves caused thousands of deaths in Europe and south-west Asia. However, the variability attributable to natural climate also produced benefits to society, ranging from the abundance of enriching sunlight for vegetable and orchard crops in western Europe, to the above normal rainfall across the Sahelian region of western Africa and the enhanced precipitation over Afghanistan and neighbouring countries. One of the major challenges for the meteorological (M. Jarraud) and hydrological communities is the need to contribute Secretary-General 4

GLOBAL TEMPERATURES 0.8 Figure 1 — Combined (a) Global DURING 2003 0.6 annual land (near surface) 0.4 and sea-surface temperature anomalies from 1861-2003 The global mean surface temperature in 2003 0.2 (departures in degrees was 0.46°C above the 1961-1990 annual aver- 0 age. This value makes 2003 the third warmest Celsius from the average in -0.2 the 1961-1990 base period) year in the instrumental temperature record -0.4 Temperature anomaly for (a) the globe; (b) the since 1861, just behind 2002 (+0.48°C). The northern hemisphere north of -0.6 Smoothed with a warmest year remains 1998 (+0.55°C). Globally- binomial filter 30°N; (c) the Tropics -0.8 averaged temperatures in the lower and middle (30°N-30°S); and (d) the 0.8 troposphere derived from NOAA satellites also (b) Northern hemisphere (north of 30°N) southern hemisphere south of indicate that 2003 was the third warmest year 0.6 30°S. The solid red curves on record for that part of the atmosphere since 0.4 have had subdecadal the beginning of annual satellite measure- 0.2 timescale variations ments in 1979. At the surface, all of the 10 0 smoothed with a binomial C) ° filter. Anomalies (in degrees warmest years have occurred since 1990, -0.2 Celsius) for 2003 are: including each year since 1997. The five -0.4 +0.46 (a); +0.71 (b); warmest years now include, in decreasing -0.6 +0.45 (c); and +0.15 (d). order: 1998, 2002, 2003, 2001 and 1995. Since -0.8 (Sources: IPCC, 2001 and the twentieth century, the increase in global 0.8 Hadley Centre, The Met surface temperature has been between 0.6 and 0.6 (c) Tropics (30°N-30°S) Office, and Climatic 0.7°C. The rate of change for the period since 0.4 Research Unit, University of Difference from 1961–1990 ( 1976 is roughly three times that for the past 0.2 East Anglia, UK). century as a whole. Analyses of proxy data for 0 the northern hemisphere indicate that late twentieth century warmth is unprecedented for -0.2 at least the past millennium. -0.4 Calculated separately for both hemi- -0.6 spheres, the departures of the 2003 -0.8 temperatures from the long-term average for 0.8 (d) Southern hemisphere (south of 30°S) the northern hemisphere (+0.59°C) and for the 0.6 southern hemisphere (+0.32°C) are both the 0.4 third warmest in the instrumental record. In 0.2 particular, the tropics (between 30°N and 30°S) 0 contributed to the warmth, although the land -0.2 areas poleward of 30°N and parts of the North -0.4

Atlantic were also particularly warm. Europe -0.6 experienced unprecedented heat during June, -0.8 July and August. The Mediterranean and Near 1880 1900 1920 1940 1960 1980 2000 5

90°N ° Figure 2 — Global annual 90 N (a) temperature anomaly 60°N 60°N percentiles for 2003 based 30°N on a gamma distribution for 30°N 0° the 1961-1990 base period, 0° calculated in five-degree grid 30°S boxes. Orange and brown 30°S 60°S indicate regions where the 60°S 90°S temperature anomalies were 180° 120°W60°W0° 60°E 120°E 180° 90°S estimated to be within the 180° 120°W60°W0° 60°E 120°E 180° 0 2 10 90 98 100 highest (warm) 10 and 2 90°N per cent, respectively, of the (b) ° climatological occurrences. East region had the warmest land and sea- 60 N Blue and purple indicate the surface temperature anomaly on record for June 30°N lowest (cold) 10 and 2 per and July. The northern hemisphere had the 0° cent of occurrences, warmest land and sea-surface temperature ° respectively. Note that grid anomaly on record for September and October. 30 S areas without sufficient data September 2003 was the warmest 60°S for analysis are left blank. ° (Source: Hadley Centre, September on record, exceeding the record previ- 90 S ously established in 1997, during the early stages 180° 120°W60°W0° 60°E 120°E 180° The Met Office, UK) ° of the strong 1997-1998 El Niño episode. Large- 90 N (c) scale climate patterns, such as El Niño (or the 60°N

North Atlantic Oscillation in boreal winter) often 30°N contribute to record warmth, but the moderate ° El Niño warm event in the equatorial Pacific 0 Ocean at the beginning of the year quickly faded 30°S Figure 3 — Global surface to near-neutral conditions by April. 60°S

temperature anomalies 90°S (departures in degrees REGIONAL TEMPERATURE 180° 120°W60°W0° 60°E 120°E 180° Celsius from the average in 90°N ANOMALIES (d) the 1961-1990 base period) 60°N for three-month period (a) Large portions of the northern hemisphere had 30°N December 2002-February warm conditions in 2003 that exceeded 90 per 2003; (b) March-May cent of the annual temperatures recorded in the 0° 2003; (c) June-August ° 2003; (d) September- 1961-1990 period (the 90th percentile). Part of 30 S the Mediterranean and North Africa had an November 2003. (Sources: 60°S Hadley Centre, The Met extremely warm year with temperatures exceed- 90°S Office and Climatic Research ing the 98th percentile. Only a few small areas 180° 120°W60°W0° 60°E 120°E 180° Unit, University of East experienced temperatures below the 10th Anglia, UK) percentile. –10 –5 –3 –1 –0.5 –0.2 0 0.2 0.5 1 3 5 10 6

Climate change detection and monitoring Extreme events, such as this year’s heat waves in Europe, trigger the question whether their occurrence is related to global warming. But warm (or cold) summers are, and always have been, part of natural climate variability. Single extreme events can therefore not be simply and directly attributed to anthropogenic climate change. Climate extremes, such as flood-producing rains, droughts, and severe heat and cold, have major impacts on our living conditions and activities. The need to anticipate changes in the occurrence of such extremes and the concern about anthropogenic climate change has led to increased attention on this issue. To provide more insights into changes in climate extremes, a comprehensive list of indices derived from daily surface data was developed by the Expert Team on Climate Change Detection, Monitoring and Indices of WMO’s Commission for Climatology and of the Programme on Climate Variability and Predictability (CLIVAR), assisted by the Asia Pacific Network. Subsequent analyses of these indices were undertaken for Africa, Asia, Australia, the Caribbean, Europe, North America, Russia and the South Pacific. Among the key questions addressed in the analysis were: how did the past warming affect the occurrence of temperature extremes? and was the past warming accompanied by trends in precipitation extremes? These questions require an accurate, dense and consistent data set of station N observations with at least a daily resolution. The observational series should date back as far as Number of days (out of 92) possible in order to capture the multi-decadal scale > = 71 variations that are important for climate change 61–70 detection. Near-real-time monitoring of climate 51–60 extremes with tools such as these indices, is part of 41–50 WMO’s World Climate Data and Monitoring 31–40 Programme, which also includes implementation of 21–30 methods to rescue, preserve and manage climate 16–20 data, as well as preparation and distribution of 11–15 global and regional data sets, including metadata. < = 5 An example of monitoring climate extremes is provided in Figure 4, which shows that the Figure 4 — Index for 2003 summer heat in Europe. For every location, the dot European heat wave was most pronounced over represents the number of days in the 2003 summer with maximum temperature parts of France, Germany, Switzerland, Austria and in the top 10 per cent for the local climate. The size of the dots is proportional to Italy. In these areas, the number of hot summer the number of days: blue indicates fewer days than the climatological value of days was far above the long-term average (1961- nine days; red indicates more than nine days. The precise definition of the index 1990), whereas fewer than normal hot summer days is: the number of days with maximum temperature above a site- and calendar- were observed in eastern and northern Europe. day specific threshold value, calculated as the 90th percentile of each calendar-day distribution in the 1961-1990 base period (Source: European Climate Assessment and Data Set Project, KNMI, The Netherlands) 7 Much of Europe was affected by heat Kingdom over 21 000 additional deaths were waves during the summer (June, July, August). related to the unrelenting heat. In the European Nationwide, seasonal temperatures were Alps, the average thickness loss of glaciers warmest on record in Germany, Switzerland, reached about three metres water equivalent, France and Spain. The heat waves resulted from nearly twice as much as during the previous a zone of strong high pressure over western record year of 1998. Heat waves affected other Europe related to a marked ridge of high pres- parts of the northern hemisphere, with near- Figure 5 — Significant sure in the large-scale upper atmospheric wind record temperatures observed in Canada and climatic anomalies and flow. Such “blocking highs” that persist for the United States (including Alaska and events in 2003. Average many days are not rare in Europe during Hawaii), southern Japan, southern China and global temperature was third summer. However, heated air from the south parts of Russia. In contrast, extremely low warmest on record. There has been a rise in global reinforced the strength and persistence of the temperatures with wet conditions persisted temperature of 0.6°C since heat wave. Nearly all radiation from the Sun from northern China to northern Japan during 1900. (Sources: National was converted to heat because of the soil and July and August. Climatic Data Center, vegetation dryness. At many locations, temper- In India, Pakistan and Bangladesh, a pre- NOAA, United States and atures rose above 40°C. In France, Italy, The monsoon heat wave brought peak temperatures WMO) Netherlands, Portugal, Spain and the United in May of between 45°C and 49°C. May is

Eastern U.S. North-east U.S. - February snowstorm. Numerous new Second lowest September sea-ice extent on Northern hemisphere snow cover extent. Second greatest Tropical Storm Linfa - Crossed the Philippines Persistent wetness 24-hour snowfall and storm total records record for Arctic. Lowest was in 2002 snow cover extent on record for northern hemisphere winter in May with wind speeds of 100 km/hr Annual anomalies of +1-2°C. Typhoon Soudelor - Peak wind speeds of Dry in central and Siberia 215 km/hr in June. Heavy rain in Japan Alaska western Europe R Annual anomalies of +2°C Typhoon Imbudo - Strongest typhoon to hit Canada Above average Europe Temperatures in the Philippines in 5 years with wind speeds of warmth in all Annual n Russia Siberia and Kazakhstan 240 km/hr. Also impacted China in July anomalies +1-2°C Major heatwave in summer. Large-scale forest fires in 4 seasons 21 000 deaths °C Typhoon Etau - 165 km/hr winds in August spring and summer and over 400 mm rain in Japan North America France, Portugal Typhoon Krovanh - 176 km/hr peak winds in 10th lowest winter snow and Mediterranean Western Asiaa Long-term ddrougroug China. Also impacted Viet Nam in August cover extent on Severe wildfire Typhoon Maemi - Peak wind speeds of record for 2002/2003 activity in July v and August 280 km/hr. More than 130 deaths in the Western U.S. India and much of Asia Republic of Korea in September and Continuation of Cold January. More than US$ 4.1 billion estimated damage multi-year drought Warmest summer on record 2 500 fatalities conditions for France, Switzerland, 12 typhoons Typhoon Soudelor Spain and Germany Sahel affected China Typhoon Etau in 2003 Above normal Linfa Western wildfires rainfall in India, Pakistan Tropical Storm Costliest. Over 300 000 September. Deadly heat wave in May/June. Typhoon Maemi hectares burned in Temperatures reached above Above normal Typhoon Krovanh California in October crops for 2003/04 50°C. 1 500 deaths. Indian monsoon rainfall 102% of normal overall. Typhoon Imbudo Distributed evenly Marty Hurricane Colombia Ethiopia, Eritrea Indonesia, Malaysia 12 deaths. Approximately Flooding in Hurricane Juan Drought continued to affect and the Philippines 4 000 homes damaged in December Category 2 at food supplies Heavy monsoon rainfall in southern Baja California landfall. Eastern December caused flooding Hurricane Fabian eyewall winds Tropical Cyclone Delfina - December/ and landslides Mexico Hit Bermuda at directly over January. 100 km/hr at its peak. Improving drought Peru category 3. Halifax. 8 deaths Heavy rainfall in Mozambique conditions in Temperatures reach Caused US$ 300 million damage northern Mexico as low as -20°C Hurricane Isabel in southern Peru in July Category 5 in Atlantic. Tropical Cyclone Manou - May. 140 km/hr Category 2 at landfall. winds at landfall in Madagascar. 265 fatalities Dry in eastern May tornado outbreak - 16 deaths. Damage Australia most tornadoes (412) of any estimated at US$ 2.3 billion 10-day period. 42 deaths. Zimbabwe and Mozambique Australia Atlantic hurricane season Drought early in the year. Heat wave in September. Tropical Cyclone Ami East Pacific hurricane season Brazil Above average activity. Relief in austral spring New all-time Australian September Crossed Fiji January 16 named storms. 7 hurricanes. Torrential rain and flooding in 16 named storms. record for daily maximum temperature with wind speeds of First season since 1977 with no South Africa, Botswana 185 km/hr Rio de Janeiro in January 7 hurricanes Continued drought of 43.1°C at West Roebuck major hurricanes Southern Ethiopia, Somalia, Kenya Moderate El Niño fades to Wettest conditions in Tropical Cyclone Erica neutral conditions by Argentina 70 years in some areas Wildfires and drought in Peak winds of 185 km/hr as northern hemisphere Santa Fe - Flooding in April/May. south-east Australia in it crossed New Caledonia in spring Several days of heavy rain. January and February March Salado River rose 508 mm in 12 hours Antarctic ozone hole largest on record, 28 million km2 in late September 8 usually the warmest month of the year in India 90°N Figure 6 — Precipitation and heat waves often occur prior to the onset of anomalies for 2003 60°N the summer monsoon, but this year’s heat was (departures in millimetres particularly harsh, with a death toll of at least 30°N from the average in a 1979- 1 500 people. This contrasted strongly with the 1995 base period). Green unseasonably low temperatures observed in 0° indicates regions that received above normal northern India in January and December. ° 30 S precipitation, while grey Maximum temperatures then were 4 to 5°C depicts regions that were 60°S below normal, which resulted in more than drier than normal. Areas in 2 500 fatalities. In neighbouring Pakistan, Nepal 90°S white have departures within ° ° ° ° ° ° ° and Bangladesh, the combination of cold 180 120 W60W0 60 E 120 E 180 +/– 50 mm of the weather and persistent fog claimed hundreds of –400 –300 –200 –100–50 50 100 200 300 400 climatological value. lives in January. Precipitation values are During the northern hemisphere winter, rainfall during the rest of the year, the impacts obtained by merging large areas in central and eastern Europe saw of the drought remained for much of 2003. raingauge observations and episodes of very cold weather. In north-western In Africa, severe drought conditions contin- satellite-derived precipitation Russia, temperatures reached –45°C in January. ued to affect much of Botswana, Zimbabwe, parts estimates. (Source: Climate For the third year in a row, Mongolia experi- of South Africa and Mozambique in early 2003. Prediction Center, NOAA, United States) enced a cycle of dry summer/cold winter with The amount of rainfall in Maputo between devastating effects on livestock. During the October 2002 and January 2003 was the lowest austral winter, a cold wave in the Peruvian high- received since 1951-1952. Areas in northern lands led to the reported deaths of more than Mozambique, eastern Zimbabwe, southern 200 people as temperatures in areas above Malawi, and eastern Zambia did benefit from 4 000 m dropped below –20°C in July. above-normal precipitation during the rainy season, but much of the rainfall was produced by DROUGHT IN SOME REGIONS tropical cyclones and often was accompanied by flooding. The erratic rainy season had varying Dry conditions and record warmth in Australia effects on crops, but led to an overall increase in promoted wildfires that devastated parts of the production in that area. Above normal rainfall south-east. A massive complex of bushfires, throughout most of the Sahelian region of west- which burned for 59 days during January and ern Africa improved their drought situation, and February, destroyed over 3 million hectares. At grain and cotton harvests were above normal. In the beginning of 2003, records indicated that in eastern Africa, the drought in northern parts of the 11-month El Niño-related dry period (March Ethiopia and Eritrea continued to hurt agricul- 2002 to January 2003) 90 per cent of the coun- ture and food security. try received rainfall below that of the long-term Near year’s end, moderate to extreme median, with 56 per cent of the country receiv- drought affected 37 per cent of the United ing rainfall in the lowest 10 per cent of totals States (excluding Alaska), in some areas for the recorded since 1900. Despite near normal fourth or fifth year in a row. The persistent lack 9 of adequate rain and snowfall left reservoirs As in other years, the Asian summer throughout much of the West below average monsoon, which typically lasts from June to near year’s end. However, even lower levels of September, sometimes brought heavy rain and many reservoirs in the West were reported flooding to parts of Pakistan, northern India, during periods of persistent drought in the Nepal and Bangladesh. The Ganges River 1950s and 1960s. In northern Mexico, drought reached its highest level since 1975 causing conditions improved in 2003. hundreds of flood-related deaths. However, The most costly wildfires on record in the overall total rainfall in India was near normal United States occurred in southern California (102 per cent of the long-term average) and the in late October, whereas British Columbia monsoon rains were well distributed through- (Canada) experienced its most costly wildfires out the season and across the country. ever during summer. Heavy autumn and winter Heavy monsoon rains also brought rainfall ended the drought conditions, but flooding to China’s Yellow River basin and brought flooding in both areas. some of its tributaries between June and The drought in Europe adversely affected October. The death toll in China reached almost agriculture, electricity and water supply. Spain, 2000, which was lower than that of earlier Portugal, France and countries in central and events in 1991 and 1998. Earlier in the year, eastern Europe and Asia also suffered from parts of the flooded area were affected by the intense forest fires. In Afghanistan and neigh- worst drought in 50 years. Viet Nam and bouring countries, rain and snowfall brought Thailand saw heavy rains and severe flooding relief from drought conditions that had built up during their rainy season, particularly in over the past four years. During July to August, October. Flood waters killed more than 100 extremely high temperatures with extremely dry people and damaged agriculture and infrastruc- conditions persisted over southern China to ture. Climatologically, Viet Nam and southern southern Japan. In southern China, more than Thailand receive most of their rainfall from the nine million people were confronted with a lack Asian monsoon during the June-November of drinking water. period. Indonesia suffered from landslides trig- gered by hours of heavy rains in January. RAINFALL AND FLOODING Landslides later in the year, in Indonesia, Malaysia and the Philippines caused deaths Global precipitation over land areas was below and disrupted local infrastructure. the 1961-1990 average in 2003 for the third year The El Niño event at the beginning of the in a row, with areas of rainfall deficiencies year had a noticeable impact on the south-west including the eastern part of Australia, parts of Pacific’s rainfall anomalies with above average China and India, central and western Europe annual rainfall over Kiribati and below average and Brazil. Positive precipitation anomalies rainfall over much of New Caledonia and Fiji. were observed in Indonesia, the eastern part of In Africa, heavy seasonal rains in April led the United States and the north-western parts to flooding in Kenya and southern parts of of South America. Ethiopia and Somalia, with similar conditions 10 in western Eritrea and north-east Sudan in July. 3.0 Figure 7 — Monthly sea-ice Some areas experienced the wettest conditions 2.5 (a) Arctic extent anomalies for 1973- 2.0 in 70 years. 1.5 2003 (departures in millions 2 In Brazil, torrential rains in January 1.0 of km from the average in brought flooding to Rio de Janeiro, triggering 0.5 the 1973-2003 base period) 0.0 )

2 for (a) the Arctic and (b) the deadly mudslides. The Argentine province of -0.5 km

6 Antarctic. The values are Santa Fe experienced the worst flooding since -1.0 derived from satellite passive the 1800s in late April/early May, affecting water -1.5 -2.0 microwave sounder data. quality and agricultural production. Colombia 3.0 (Source: Hadley Centre, experienced flooding in December. 2.5 (b) Antarctic The Met Office, UK) Snowstorms in February brought numer- 2.0 1.5 ous new snowfall records to the eastern United Sea-ice extent anomalies (10 1.0 States, resulting in a number of weather-related 0.5 deaths. In November, rainfall records were set 0.0 -0.5 in portions of coastal British Columbia, as up -1.0 to 470 millimetres of rain in a six-day period -1.5 caused the worst flooding in a century. Severe -2.0 weather with abundant rainfall and snow 1975 1980 1985 1990 1995 2000 2005 caused flooding in countries across Europe in January, with the largest impacts in the Czech above the 1944-1996 average of 9.8, but consis- Republic. South-eastern France was hit by tent with a marked increase in the annual flooding in early December. number of tropical systems since the mid-1990s. The northern hemisphere snow cover The absence of El Niño conditions in the Pacific extent during the 2002/2003 winter season was contributed to the very active storm season. One the second highest since records based on visi- named storm formed in April, well before the ble satellite imagery began in 1967. This beginning of the hurricane season, and two interrupted a long series of mostly negative named storms formed in December, after the anomalies that accompanied a trend towards traditional end of the hurricane season. Seven of warmer winter temperatures. Colder than the named storms were classified as hurricanes normal conditions contributed to greater snow and three of those were ‘major’ (category three cover than normal across large parts of western or higher on the Saffir-Simpson scale). Hurricane and southern Asia, as well as eastern Europe, Isabel had by far the largest impact in the United in particular during February (see back cover). States from the summer’s Atlantic storms. Hurricane Juan was the worst hurricane to hit TYPHOONS, HURRICANES AND Halifax, Nova Scotia in modern history. Mexico TROPICAL CYCLONES was hit by a series of hurricanes and tropical storms during August, September and October The 2003 Atlantic hurricane season saw the that brought heavy rains, flooding, and land- development of 16 named storms, which is well slides to areas across the country. 11 In the eastern Pacific, the hurricane season size of the 2003 ozone hole (28 million square began slowly, although 16 named storms even- kilometres), as reached in late September, tually developed, close to the 1966-1996 matched the all time record size reported for average of 16.4. While none of the storms September 2000 (see front cover). This is in reached hurricane strength until late August, stark contrast to the ozone hole in 2002, which seven storms reached hurricane strength by the split in two during late September and was the end of October. This is the first year since 1977 smallest in more than a decade. As it had in that no hurricanes have reached category three 2000, the ozone hole in 2003 dissipated earlier strength. than usual. For the western north Pacific, activity was Variations in size, depth and persistence of slightly depressed in 2003 with only 21 named the ozone hole are due to year-to-year changes storms observed, which is below the 1971-2000 in the meteorological conditions in the lower average of 26.7 and the third fewest since 1951. stratosphere over Antarctica, rather than to Fourteen reached typhoon intensity and some changes in the amount of ozone-depleting of them affected Asian countries. Typhoon substances present in the ozone layer. Maemi passed over southern Japan and made Measurements show that most of these landfall on the Korean Peninsula on September substances are decreasing in the lower atmos- 12, resulting in more than 130 deaths and phere and they appear to have reached their massive property damage. peak in the critically important ozone layer in The south-west Indian Ocean cyclone the stratosphere. There is a delay in the cleans- season was active with an above normal ing of these substances from the ozone layer; it number of named storms. In Sri Lanka, heavy is expected that it will require decades before rainfalls in May from Tropical Cyclone 01B exac- the stratosphere returns to pre-ozone hole erbated already wet conditions, resulting in conditions. flooding and landslides and killing at least 250 people. The flooding is considered the worst to ARCTIC SEA-ICE affect the region in 50 years. In total, nine tropical cyclone occurrences Northern hemisphere sea-ice extent was affected the south-west Pacific region in 2003, 5.4 million square kilometres in September 2003, five of which were classified as major which was nearly as low as the record low of 5.3 hurricanes. million square kilometres in September 2002 (satellite monitoring began in 1973, with contin- ANTARCTIC OZONE HOLE uous satellite observations from 1978). The low sea-ice extent observed in recent years is consis- A comprehensive analysis of integrated tent with new analyses of satellite data, which ground-based and satellite measurements over show that the Arctic region warmed significantly and near Antarctica showed that the maximum in the 1990s compared to the 1980s. WMO STATEMENT ON THE STATUS OF THE GLOBAL CLIMATE IN 2003

New Area of ozone hole (million km Zealand -40 10 7 10 10 10610180170170 160 150160150 130140

-0.5-1.0 0.5 1.0 5

For information about WMO, please contact: For more information about the contents of this brochure, please contact: Communications and Public Affairs Office World Climate Programme Department World Meteorological Organization World Meteorological Organization 0 7bis, avenue de la Paix 7bis, avenue de la Paix DecemberNovemberOctoberSeptemberAugust P.O. Box 2300 P.O. Box 2300 CH-1211 Geneva 2, SWITZERLAND CH-1211 Geneva 2, SWITZERLAND Tel: (+41-22) 730 83 14 / 730 83 15 Tel: (+41-22) 730 83 77 Fax: (+41-22) 730 80 27 Fax: (+41-22) 730 80 42 E-mail: [email protected] E-mail: [email protected] Web: http://www.wmo.int Web: http://www.wmo.ch/web/wcp/wcp_prog.htm World Meteorological Organization WMO-No. 966