Wmo Statement on the Status of the Global Climate in 2005

WMO STATEMENT ON THE STATUS OF THE GLOBAL CLIMATE IN 2005

40˚N 40˚N

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28 26 24 22 0˚ 100˚W 20 80˚W 60˚W 40˚W 20˚W 18 16 14 12 10 8 6 4 2 0 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

World Meteorological Organization Weather • Climate • Water WMO-No. 998 2

Front cover: Top: Tracks of the hurricanes in the 2005 North Atlantic hurricane season. (Source: National Climatic Data Center, NOAA, United States)

Bottom: Annual number of named storms (blue) and major hurricanes (red) in the North Atlantic Ocean for the period 1945-2005. (Source: National Climatic Data Center, NOAA, United States)

Back cover: Left: Mean total ozone (in Dobson units) over the southern hemisphere during September 2005 based on ground-based measurements. (Source: World Ozone and Ultraviolet Radiation Data Centre, Environment Canada)

Right: Accumulated precipitation anomalies (departures in millimetres from a 1979-2000 base period) during the 2005 May to August season for Europe. Green indicates areas that received above normal precipitation during the period while pink depicts those regions that were drier than normal. Areas in white show regions where departures are within +/- 25 mm of the average seasonal value. Precipitation values are obtained by merging rain-gauge observations and satellite-derived precipitation estimates. (Source: Climate Prediction Center, NOAA, United States)

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, 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, United Kingdom, the Climatic Research Unit, University of East Anglia, United Kingdom; and the National Climatic Data Center and the Climate Prediction Center of the National Oceanic and Atmospheric Administration World (NOAA), United States. Other contributors were from the following WMO Member countries: Argentina, Meteorological Australia, Canada, China, Fiji, France, Germany, India, Japan, Mauritius, Morocco, New Zealand, Norway and Organization Sweden, as well as the International Research Institute for Climate and Society, United States, the IGAD Weather • Climate • Water Climate Prediction and Applications Centre in Nairobi and the AGRHYMET Regional Centre in Niamey. Geneva - Switzerland 3

FOREWORD

The World Meteorological Organization (WMO), through decades. The least developed countries are more the Commission for Climatology and in cooperation with affected by these hazards. The adequate integration of its Members, has issued annual statements on the risk assessment and early warnings, with prevention and status of the global climate for the past 12 years. The mitigation measures, can prevent natural hazards from statement for 2005 describes extreme weather and becoming disasters. The role of WMO and the National climate events and provides a historical perspective on Meteorological and Hydrological Services (NMHSs) is the variability and trends of surface temperatures that therefore fundamental in the identification, assessment have occurred since the nineteenth century. The state- and monitoring of risks and the provision of early ments complement the periodic assessments of the warnings. In the longer term, climate changes could WMO/UNEP sponsored Intergovernmental Panel on result in increased frequency of some extreme events Climate Change (IPCC) and are intended to provide cred- such as heatwaves, droughts and floods. For sustainable ible scientific information on climate and its variability. development, there is a need for a better monitoring and The year 2005 was most likely one of the two understanding of the climate system as well as the warmest years on record since 1850. The 2005 hurricane further development of capabilities for predicting natural season saw some of the most destructive hurricanes on climate variability and human-induced climate change. record, which claimed more than 3 000 lives in Central A major challenge for the meteorological and America and the United States. Disastrous floods and hydrological communities is to work towards a major landslides due to extreme precipitation events were also reduction of the fatality rate associated with natural reported worldwide. Prolonged drought conditions disasters. Enhanced weather, climate and hydrological continued to affect parts of Africa, Australia and the services are being implemented to contribute to reduc- western United States. In 2005, western parts of Europe ing the adverse human, social and economic impacts of were also under the grip of a severe drought. Arctic sea natural disasters and extreme weather and climate ice during September 2005 was the lowest on record and events. Through its Programmes, WMO contributes below the average for the fourth consecutive year. The actively to the timely provision of authoritative climate ozone hole in 2005 was the third largest recorded after statements, assessments and reviews for the benefit of 2000 and 2003. In December, central Europe and central humankind in the twenty-first century. and eastern parts of Asia experienced significantly colder than average temperatures. The impacts of climate variability and climate change, especially extreme events on human and natural systems, pose numerous challenges to sustainable development. In 2005, damages and casualties caused by extreme weather and climate events were high and alarming. The economic impact of natural disasters has (M. Jarraud) shown a marked upward trend over the last several Secretary-General 4

GLOBAL TEMPERATURES 0.6 Figure 1 — Combined ( ) Global DURING 2005 0.4 a annual land (near surface) 0.2 and sea surface temperature The analyses made by various leading centres 0.0 anomalies from 1861-2005 (departures in degrees indicate that the global mean surface temper- −0.2 Celsius from the average in ature in 2005 was 0.47°C to 0.58°C above the −0.4 the 1961-1990 base period) −0.6 1961-1990 annual average of 14°C. This places for: (a) the globe; (b) the 2005 as one of the two warmest years in the −0.8 northern hemisphere; (c) the −1.0 temperature record since 1850. (The year Tropics (30°N-30°S); and 1998 had annual surface temperatures aver- (d) the southern hemisphere. aging 0.52°C* above the same 30-year mean.) 1.0 The solid red curves have had 0.8 (b) Northern hemisphere The last 10 years, 1996-2005, with the excep- 0.6 sub-decadal timescale tion of 1996 and 2000, are the warmest years 0.4 variations smoothed with a 0.2 binomial filter. Anomalies on record. 0.0 (in degrees Celsius) for 2005 The latest improved analysis of global −0.2 temperature made by the Hadley Centre, The −0.4 are: (a) +0.47; (b) +0.65; Met Office, UK, marks the year as the second −0.6 (c) +0.45; and (d) +0.28. −0.8 (Sources: Hadley Centre, warmest (0.47°C above average). Based on −1.0 −1.2 The Met Office, UK, similar improved temperature analyses, but and Climatic Research different methodology, the National Climatic 0.8 Unit, University of Data Center, NOAA, United States, ranks 2005 0.6 (c) Tropics (30°N-30°S) East Anglia, UK) as the warmest year (0.52°C above the 1961- 0.4 1990 annual average). The analysis of the 0.2 NOTE: There are some

Goddard Institute of Space Studies, United 1961-1990 (°C) from Difference 0.0 differences in annual States, also ranks the year as the warmest −0.2 anomalies between the (0.58°C above the 1951-1980 annual average). −0.4 present and earlier WMO All the temperature values have uncertainties, −0.6 statements. In this new which arise mainly from gaps in data coverage. −0.8 analysis, more quality- −1.0 improved, sea surface The sizes of the uncertainties are such that temperature and land the global average temperature for 2005 is 0.4 station data have been used. statistically indistinguishable from that of 0.2 (d) Southern hemisphere 1998. Based on the Hadley Centre analyses, 0.0 averaged separately for both hemispheres, −0.2 surface temperatures in 2005 for the northern −0.4 *This value is based on the new hemisphere (0.65°C above the 1961-1990 aver- −0.6 temperature analysis of the age) were the warmest and for the southern −0.8 Hadley Centre, UK, introduced hemisphere (0.28°C above the 1961-1990 aver- −1.0 for the first time this year. In the earlier temperature analysis, −1.2 age) were the fifth warmest in the instrumental the temperature anomaly value 1860 1880 1900 1920 1940 1960 1980 2000 record from 1850 to the present. for 1998 was +0.54°C. 5 Since the beginning of the twentieth 90th percentile). Parts of the North Atlantic century, the global average surface tempera- and Indian Oceans had warm temperatures ture has increased by about 0.6°C. However, exceeding the 98th percentile. Only a few small this increase has not been continuous and has areas in the southern hemisphere experienced Figure 2 — Global annual risen sharply since 1976. temperatures below the 10th percentile. temperature anomaly Areas of significant warmth were wide- The large-scale climate phenomenon El percentiles for 2005 based on a gamma distribution for spread with large areas of Africa, Australia, Niño can contribute to above average warmth, the 1961-1990 base period, Brazil, the Russian Federation, Scandinavia, as was the case with the extremely strong calculated in five-degree grid Canada, China and the south-west United 1997/1998 episode. A weak El Niño episode boxes. Orange and red States showing significantly above average that developed in mid-2004 continued through indicate regions where the temperatures. Much of the North Atlantic and the beginning of 2005, but sea surface temper- temperature anomalies were south-west Pacific Oceans were also signifi- atures in the central and east central equatorial estimated to be within the cantly warm, as was the Gulf of Alaska. Sea Pacific decreased early in the year and the highest (warm) 10 and surface temperatures in the North Atlantic in episode ended by late February. The record 2 per cent, respectively, of the 2005 were the warmest on record. warmth in 2005 is notable as there was little climatological occurrences. influence of the El Niño event on the 2005 Blue and purple indicate the global temperatures. lowest (cold) 10 and 2 per REGIONAL TEMPERATURE cent of occurrences, ANOMALIES For Australia, 2005 was the hottest year respectively. Note that grid since records commenced in 1910, with about areas without sufficient data Large portions of the northern hemisphere 95 per cent of the continent experiencing for analysis are left blank. experienced warm conditions in 2005 that above average mean temperatures. The previous (Source: Hadley Centre, exceeded 90 per cent of the annual tempera- annual temperature record was set in 1998. The Met Office, UK) tures recorded in the 1961-1990 period (the The nationwide maximum temperature anom-

90°N aly in April was +3.11°C, the largest anomaly recorded for any month since 1950. During

60°N the January-May period, the hottest maximum temperatures on record exacerbated the excep- 30°N tionally dry conditions. In India, Pakistan and Bangladesh, extremely 0° harsh heatwaves in May and June brought maximum temperatures of between 45°C and 30°S 50°C. The maximum temperatures over these regions were 5°C to 6°C above the long-term 60°S average. The delayed south-west monsoon rains allowed the heatwave to persist into 90°S 180° 120°W 60°W 0° 60°E 120°E 180° June, claiming at least 400 lives in India. A severe heatwave gripped the south- western United States from early to mid-July, 0% 2% 10% 90% 98% 100% setting up numerous temperature records. 6

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(a) 5 Central Canada experienced its warmest and Figure 3 — Global surface 2

5 1

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90°S Somalia and Kenya were at risk of starvation 180° 120°W 60°W 0° 60°E 120°E 180° due to the effects of recent droughts. Sporadic rainfall during the 2004/2005 rainy season −5 −2 −1 0 1 2 5 caused serious shortfalls in the cereal harvest 7 in Zimbabwe, Malawi, Angola and Mozambique. Arctic sea ice At least 5 million people in Malawi were threat- Lowest extent on record in September Northern hemisphere snow cover extent Alaska ened with hunger arising from the worst Least extensive snow cover on record for August and July; Third warmest North-east United States/ thirteenth least extensive snow year (out of 33) summer drought in a decade. Canada South-east Canada Eastern Europe Russian Federation Annual temperature Major winter storm (January); Severe flooding (May-August) Annual temperature anomalies o Western Europe Multi-month drought conditions also United States wildfires anomalies of 2-3 C snowiest month on record for Boston o Severe summer of 2-4 C above average Record area burned (about above average Balkans 3.5 million hectares); much in Northeast United States drought; forest fires affected much of western Europe during July, Severe winter weather Tajikistan, Pakistan, India Alaska (1.8 million hectares) Record wet October, August and September. During the period 3 separate storm systems; and much below average Severe winter storms; snow and North-west United States also heavy rain and flooding winter temperatures avalanches (January/February), October 2004 to June 2005, rainfall was less Severe winter drought Central United States in April rain/flooding in southern Pakistan/Afghanistan (February-March) Western United States Expansion of severe Hurricane Wilma (October) than half the normal in areas of the United drought in summer Third category 5 storm of the July heatwave; many season; lowest central pressure new daily heat records on record for the Atlantic; Kingdom, France, Spain and Portugal. Neigh- category 4 at landfall in Mexico, Western Europe/ North Africa South-west United States Hurricane Emily category 3 in Florida Islamic Republic of bouring Spain and Portugal experienced the Category 4, 155 mph Heatwave (July) Heavy rain and flooding in May–July Multiple strong winter Hurricane Katrina (August) Iran (north) Indian monsoon rainfall at peak intensity Category 5 storm, category 3 at worst drought conditions since the late 1940s, storms; record rain and snow Snow (February), worst Near normal (98%) for 2005 landfall, led to over 1 300 deaths Algeria (north) accumulations in in Louisiana and Mississippi Typhoon Haitang (July) with 97 per cent of Portugal affected by severe East Pacific hurricane season Heaviest snowfall Tehran since 1964 Below average activity; Hurricane Rita (September) since 1950 (January) Second category 5 storm of the season, India 15 named storms, Typhoon (August) to extreme drought. The dry conditions also Central America made landfall in Texas at category 3 Africa ITCZ Over 944 mm of India/Pakistan Talim 7 hurricanes Landfall at 195 km/h aggravated wildfires in the region. Heavy rainfall/mudslides (October), Hurricane Dennis (July) North of mean position in June/July rain in 24 hours for Heatwave in May/June; hundreds of deaths; Category 4 at landfall in Cuba contributed to active early Atlantic Mumbai in July; temperatures near 50°C Typhoon Damrey (September) major flooding The long-term hydrological drought possibly related to Hurricane Stan Atlantic hurricane season hurricane season Worst typhoon to strike Hainan in from monsoon rains several decades, about 150 deaths Venezuela, Colombia Above average activity India continued for southern and eastern Australia, 27 named storms – most on record Rain and Thailand Heavy rainfall and 14 hurricanes – most on record Worst drought in 7 years (April), flooding/landslides (February) 7 “major” hurricanes severe Two February tropical cyclones but eased slightly in the second half of the Greater Horn flooding in water shortages Both affected Samoa, Cook Islands Weak El Niño transitions to neutral Continued long-term south-east : sustained winds of 260 km/h, year. The period January to May was exception- ENSO in boreal spring drought (October-December) Olaf Brazil gusts up to 300 km/h Developing La Niña at year’s end Drought, worst in 60 years; ally dry for much of Australia, with 44 per Percy: sustained winds of 240 km/h lowest Amazon flow Tropical cyclone Ingrid cent of the continent experiencing rainfall Guyana in 30 years Angola Percy Heavy rainfall (January–February), Sustained winds of 250 km/h; Torrential rain (March); in the lowest 10 per cent of the recorded Georgetown flooded only cyclone on record to make Olaf severe flooding landfall in 3 Australian states as a major cyclone Australia totals. During this period, Australia received Chile Dry January-May; dryness Heavy snow (May) Brazil (south) exacerbated by warmest an average of only 168 mm of rainfall, the Western Australia in Andes; worst Drought (December-March); South-eastern Africa year on record nationwide Equalled all-time monthly more details on Australia snowstorm in 30 years severe agricultural impacts, Continued long-term second lowest January-May total since records maximum temperature water shortages drought; worst drought for Australia at commenced in 1900. in 10 years in Malawi Nyang Station (44.8°C, January) Across the United States, moderate to Australia severe drought persisted throughout parts of Cold temperatures; snow at sea level in Victoria for New Zealand the Pacific North-West eastward into the first time in over 50 years Heavy rain (May), flooding northern Rocky Mountains. At the end of around the Bay of Plenty winter, moderate to extreme drought affected Antarctic ozone hole – 24.4 million km2 at its peak 72 per cent of the Pacific North-West. Below in mid-September; above 10-year average normal rainfall beginning in December 2004 caused severe drought conditions over southern parts of Brazil, where corn and soybean crops were severely damaged. In Brazil, the Figure 4 — Significant climatic anomalies and events in 2005. The southernmost state of Rio Grande do Sul, average global temperature was the second warmest on record. There which is one of the country’s most prolific has been a rise in global temperature greater than 0.6°C since 1900. agricultural states, was the worst affected. (Source: National Climatic Data Center, NOAA, United States) 8

Figure 5 — Global ranked 0.6 The state of Amazonas experienced the worst 300 fatalities and caused considerable adverse surface temperatures showing 1998

2005 drought in nearly 60 years, resulting in record socio-economic impacts. The north-east monsoon 2003 2002 2005 the last 50 warmest years. 2004 low water levels in the Amazon River. In also produced extremely heavy rainfall in parts The size of the bars indicates 2001 2004−1990 1997 1989−1970 October, drought conditions extended further of the Malay Peninsula, Sri Lanka, the central the uncertainty associated 1969−1950 south into neighbouring Paraguay. By the end Philippines, Thailand and Viet Nam. In Thailand, 1995 with each year. Values are 0.4 1999 1990 2000 1949−1930 of the year, drought affected much of the at least 52 deaths were attributed to one of the

HadCRUT3 temperature 1991

1983 1929−1860 1994

1987 central United States from the southern Great worst floods in nearly 30 years. In Viet Nam, values. (Sources: Hadley 1988 1996 1981 1944 1993

1980 Plains to the western Great Lakes. Parts of flooding claimed at least 69 lives and caused 1941 1989

Centre, The Met Office, UK, 1878 1877

0.2 1992 1973 1977 1939 1979 and Climatic Research 1940 Illinois, Arkansas, Oklahoma and Texas had damage to property. 1986 1938 1982 1945 1937 1969 1943 1984 1985 1958

1942 the driest March-December in the 111-year During the third week of June, consecutive Unit, University of 1962 1961 1963 1953 1978 1972 1970 East Anglia, UK) 1952 record. heavy rainstorms in parts of Fujian, Guangdong

Anomaly (°C) wrt 1961-1990 0.0 and Guangxi provinces in southern China RAINFALL AND FLOODING killed at least 170 people and affected about 21 million people. Heavy rainfall across south- Global precipitation in 2005 was near the 1961- ern China continued into July, with floods

-0.2 1990 average. Wetter than average conditions affecting the upper reaches of the Huaihe 10 20 30 40 50 prevailed over Central America, eastern parts River Basin. Across northern China, heavy Rank of Europe, India, China and Canada. Drier than rainfall during late September to early October Figure 6 — Annual average conditions were widespread across produced extensive flooding in the Hanjiang precipitation anomalies eastern Australia, Brazil, parts of Western River and the Weihe River basins, affecting (departures in millimetres Europe, Central Africa, and the Mississippi about 5.52 million people. from a 1979-2000 base valley and southern Great Plains region in the Persistent heavy rains during the period period) for 2005. Green and United States. May-August led to destructive flooding in yellow indicate areas that The south-west monsoon during June- Eastern Europe, particularly in Romania, 60°N received above normal September brought unprecedented heavy rain Bulgaria, Hungary and The former Yugoslav precipitation for the calendar year 2005 as a whole while and widespread massive flooding to parts of Republic of Macedonia, causing damage to prop- 30°N pink and red depict those western and southern India, affecting more erty, infrastructure and agriculture. Torrential regions of the world that were than 20 million people and resulting in more rainfall in mid-August also flooded sections of drier than normal. Areas in than1 800 deaths. On 27 July, Mumbai recorded Switzerland, Austria and southern Germany EQ white show regions where unprecedented heavy rainfall of 944 mm in the and the Czech Republic. The hardest hit area departures are within previous 24 hours, which is an all-time 24-hour was Romania where 66 flood-related fatalities 30°S +/- 50 mm of the average rainfall record for the city. The devastating and losses of at least US$ 1.9 million in annual value. Precipitation floods in Mumbai caused economic losses of damage were reported. During April and May, values are obtained by about US$ 3.5 million. floods and landslides were widespread in 60°S merging rain-gauge Heavy rainfall continued unabated in southern parts of the Russian Federation, observations and satellite- south-eastern parts of India, during the north- derived precipitation affecting more than 4 000 people. In the first 180° 120°W 60°W 0 60°E 120° 180° estimates. (Source: Climate east monsoon season of October-December. week of January, a severe winter storm affected Prediction Center, NOAA, The associated devastating floods affected parts of Sweden and neighbouring countries -400 -300 -200 -100 -50 50 100 200 300 400 United States) more than 2 million people with at least including Denmark and Latvia, causing an 9

Tropical cyclones and global warming

In terms of overall hurricane activity (number and intensity of storms), the 2005 Atlantic hurricane season has been clearly the most active season on record. The season brought an unprecedented 27 named tropical storms that caused devastating losses across Central America, the Caribbean and the United States. Of the named storms, 14 were hurricanes, 7 of those “major” hurricanes (category 3 or higher on the Saffir-Simpson scale). On average, 10 named storms develop in the Atlantic Basin, 6 of which are hurricanes. The 2005 hurricane season broke the previous record for the most named storms (21 in 1933) and hurricanes (12 in 1969), and ties the season record for major hurricanes, first set in 1950. In Central America and the Caribbean region, the most damage occurred from Hurricanes Dennis, Emily, Stan, Wilma and Beta. In the United States, 7 storms including 4 hurricanes made landfall. Hurricane Katrina was the deadliest hurricane to hit the United States since 1928. The storm killed over 1300 people, mostly in the southern states of Louisiana and Mississippi, and produced widespread devastation along the central Gulf coast of the United States. Hurricane Wilma was the most intense Atlantic hurricane ever recorded. The first tropical cyclone on record to strike the Iberian Peninsula since 1851 was Vince. Conversely, in the eastern North Pacific, activity was below average. During the year, 15 named storms developed, compared with the average of 16, and there were also fewer strong storms. Of those 15 storms, 7 reached hurricane strength and 2 reached “major” status. In the North-West Pacific, 23 named storms developed, whereas the average is 27; 13 reached typhoon intensity. Typhoon Talim crossed south-eastern China and caused serious damage, including at least 150 deaths. In early September, typhoon Nabi caused severe damage and brought a record heavy precipitation of 1321 mm in three days in western Japan. Typhoon Longwang, which caused flash floods, was responsible for at least 80 deaths in south-east China. The south-west Indian and south-west Pacific Ocean cyclone season was also active with a near-average number of named storms. Tropical cyclone Ingrid, which lasted from 5 to 16 March, was the first cyclone recorded to reach category 5 intensity off the coast of three different Australian states, Queensland, Northern Territory and Western Australia. There is speculation that, because of the link between higher ocean temperatures and hurricanes, the increased hurricane activity in the North Atlantic is possibly linked to global warming. There is no indication of a long-term trend in the global annual frequency of tropical cyclones. Since 1995, there has been a marked increase in the annual number of tropical storms in the Atlantic Basin, largely in response to the active phase of the multi-decadal signal. Climate models suggest that global warming will result in more intense hurricanes, as increasing sea surface temperatures provide energy for storm intensification. Global data indicate a 30-year trend toward more intense hurricanes in the North Pacific, Indian, South-West Pacific and North Atlantic Oceans. However, the attribution of long-term trends in frequency and/or intensity to global warming requires a longer global data record. Similarly, the attribution of a single event such as Hurricane Katrina, regardless of how extreme, is fundamentally impossible. 10 economic loss of about US$ 2.3 billion for the of northern India received heavy snowfall, forest industry. described as the worst in two decades. In An onslaught of winter storms in early India, at least 230 people died as a result January brought exceptionally heavy rain, of the extreme winter weather. In Pakistan's snow and flooding to the south-western north-west province, 360 deaths in February United States. Los Angeles, California, expe- were attributed to flooding, landslides and rienced its second wettest rainfall season on avalanches. Heavy rains during March also record. In January, a major winter snowstorm caused flooding in parts of western Pakistan affected areas of the north-eastern United and Afghanistan, resulting in more than States with more than 30 cm of snow accu- 200 fatalities. In December, record-breaking mulation. Record rainfall occurred in the heavy snowfall occurred in parts of Japan, north-east United States in the autumn of claiming at least 80 lives. A record maximum 2005, with three storm systems affecting the snowfall of 58 cm was recorded at Akita in region. Across Canada, 2005 was the wettest December. year on record. In June, three major rain In New Zealand, the Bay of Plenty floods events in southern Alberta produced the in May were most disastrous, with unprece- costliest natural disaster in the province's dented heavy rainfall causing widespread history. Calgary experienced its wettest damage in parts of Tauranga. It was one of the month ever covering 125 years of record. wettest years on record in parts of the Bay of Heavy rains in January and February Plenty and Hawke's Bay. In the South Pacific, caused massive flooding in Guyana's capital, heavy rains and high storm surges owing to Georgetown, and surrounding areas affecting tropical cyclones Olaf and Percy impacted the more than 290 000 people. In February, at least coastal areas of Samoa, American Samoa, two weeks of heavy rainfall in Colombia and Cook Islands and Manua Islands, causing Venezuela caused river flooding and landslides coastal flooding and displacing thousands of that resulted in the deaths of at least 80 people. people. Across Costa Rica and Panama, heavy rains in January caused flooding that was ANTARCTIC OZONE HOLE responsible for displacing more than 35 000 people. In October, Hurricane Stan caused In 2005, the size of the Antarctic ozone hole flooding and mudslides over portions of was close to 2003 values and well above the Mexico, Nicaragua, Honduras and El Salvador, 1995-2004 average. The maximum size of the leading to the deaths of hundreds of people. Antarctic ozone hole, 24.4 million km2, was Cold weather and heavy snowfall that reached in the third week of September. The began in January continued in February over ozone hole in 2005 dissipated earlier than south-west Asia, causing avalanches. In parts usual, in mid-November. Based on satellite of Tajikistan, two metres of snow accumulated observations, the ozone hole of 2005 ranks as in two weeks. During February, sections of the third largest ever recorded after 2000 and northern Pakistan and neighbouring areas 2003. This year, greater ozone depletion took 11

30 Figure 7 (right) — Daily 2 ) size of the Antarctic ozone hole 2 2002 (a) Arctic (in million square km) from 25 2003 1 August to 30 November 2004 1 20 2005 for the period 2002-2005 using total ozone observations 15 from NOAA's solar back- 0 ) 2 scatter ultraviolet (SBUV/2) 10 km instrument on board its 6 −1 polar-orbiting satellites. 5 (Source: Climate Prediction of ozone hole (million km Area −2 Center, NOAA, United States) 01 August 31 August 30 September 30 October 30 November

3 place in the Arctic. During the spring of 2005, (b) Antarctic in large portions of the Arctic region, average 2 values of total ozone were 30-45 per cent lower than comparable values during the early 1 1980s. Sea-ice extent anomaly (10 0 Figure 8 (far right) — ARCTIC SEA-ICE Monthly sea-ice extent −1 anomalies for 1973-2005 Typically, September is the month with the (departures in millions of least sea-ice extent in the Arctic. By the end of −2 1970 1975 1980 1985 1990 1995 2000 2005 square km from the average September 2005, the Arctic sea-ice extent in the 1973-2005 base dropped far below the average for the fourth period) for (a) the Arctic and (b) the Antarctic. The values consecutive year. It was about 20 per cent less Arctic sea-ice extent over the last 25 years. are derived from satellite than the 1979-2004 average, the lowest extent Warmer than average Arctic temperatures and passive microwave sounder ever observed during the satellite record since an early arrival of the sea-ice melt season are data. (Source: Hadley 1979. Satellite information suggests a general the main causes for the intensification of the Centre, The Met Office, UK) decline of 8 per cent in the end of September sea-ice decline in 2005. 75°N

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