Europe and the Middle East
(2018)
In 2017, the dominant greenhouse gases released into Earth’s
atmosphere—carbon dioxide, methane, and nitrous oxide—
reached new record highs. The annual global average carbon
dioxide concentration at Earth’s surface for 2017 was 405.0
± 0.1 ppm, 2.2 ppm greater than for 2016 and the highest in
the modern atmospheric measurement record and in ice core
records dating back as far as 800 000 years. The global growth
rate of CO2 has nearly quadrupled since the early 1960s.
With ENSO-neutral conditions present in the central and
eastern equatorial Pacific Ocean during most of the year and
weak La Niña conditions notable at the start and end, the global
temperature across land and ocean surfaces ranked as the second or third highest, depending on the dataset, since records
began in the mid-to-late 1800s. Notably, it was the warmest
non-El Niño year in the instrumental record. Above Earth’s
surface, the annual lower tropospheric temperature was also
either second or third highest according to all datasets analyzed. The lower stratospheric temperature was about 0.2°C
higher than the record cold temperature of 2016 according to
most of the in situ and satellite datasets.
Several countries, including Argentina, Uruguay, Spain, and
Bulgaria, reported record high annual temperatures. Mexico
broke its annual record for the fourth consecutive year. On 27
January, the temperature reached 43.4°C at Puerto Madryn,
Argentina—the highest temperature recorded so far south
(43°S) anywhere in the world. On 28 May in Turbat, western
Pakistan, the high of 53.5°C tied Pakistan’s all-time highest
temperature and became the world-record highest temperature for May.
In the Arctic, the 2017 land surface temperature was 1.6°C
above the 1981–2010 average, the second highest since the
record began in 1900, behind only 2016. The five highest annual
Arctic temperatures have all occurred since 2007. Exceptionally
high temperatures were observed in the permafrost across
the Arctic, with record values reported in much of Alaska and
northwestern Canada. In August, high sea surface temperature
(SST) records were broken for the Chukchi Sea, with some
regions as warm as +11°C, or 3° to 4°C warmer than the longterm mean (1982–present). According to paleoclimate studies,
today’s abnormally warm Arctic air and SSTs have not been
observed in the last 2000 years. The increasing temperatures
have led to decreasing Arctic sea ice extent and thickness. On
7 March, sea ice extent at the end of the growth season saw
its lowest maximum in the 37-year satellite record, covering
8% less area than the 1981–2010 average. The Arctic sea ice
minimum on 13 September was the eighth lowest on record
and covered 25% less area than the long-term mean.
Preliminary data indicate that glaciers across the world lost
mass for the 38th consecutive year on record; the declines
are remarkably consistent from region to region. Cumulatively
since 1980, this loss is equivalent to slicing 22 meters off the
top of the average glacier.
Antarctic sea ice extent remained below average for all of
2017, with record lows during the first four months. Over
the continent, the austral summer seasonal melt extent and
melt index were the second highest since 2005, mostly due to
strong positive anomalies of air temperature over most of the
West Antarctic coast. In contrast, the East Antarctic Plateau
saw record low mean temperatures in March. The year was
also distinguished by the second smallest Antarctic ozone hole
observed since 1988.
Across the global oceans, the overall long-term SST warming
trend remained strong. Although SST cooled slightly from 2016
to 2017, the last three years produced the three highest annual
values observed; these high anomalies have been associated
with widespread coral bleaching. The most recent global coral
bleaching lasted three full years, June 2014 to May 2017, and
was the longest, most widespread, and almost certainly most
destructive such event on record. Global integrals of 0–700-
m and 0–2000-m ocean heat content reached record highs in
2017, and global mean sea level during the year became the
highest annual average in the 25-year satellite altimetry record,
rising to 77 mm above the 1993 average.
In the tropics, 2017 saw 85 named tropical storms, slightly
above the 1981–2010 average of 82. The North Atlantic basin
was the only basin that featured an above-normal season, its
seventh most active in the 164-year record. Three hurricanes
in the basin were especially notable. Harvey produced record
rainfall totals in areas of Texas and Louisiana, including a storm
total of 1538.7 mm near Beaumont, Texas, which far exceeds
the previous known U.S. tropical cyclone record of 1320.8 mm.
Irma was the strongest tropical cyclone globally in 2017 and the
strongest Atlantic hurricane outside of the Gulf of Mexico and
Caribbean on record with maximum winds of 295 km h−1. Maria
caused catastrophic destruction across the Caribbean Islands,
including devastating wind damage and flooding across Puerto
Rico. Elsewhere, the western North Pacific, South Indian, and
Australian basins were all particularly quiet.
Precipitation over global land areas in 2017 was clearly above
the long-term average. Among noteworthy regional precipitation records in 2017, Russia reported its second wettest year
on record (after 2013) and Norway experienced its sixth wettest year since records began in 1900. Across India, heavy rain
and flood-related incidents during the monsoon season claimed
around 800 lives. In August and September, above-normal
precipitation triggered the most devastating floods in more
than a decade in the Venezuelan states of Bolívar and Delta
Amacuro. In Nigeria, heavy rain during August and September
caused the Niger and Benue Rivers to overflow, bringing floods
that displaced more than 100 000 people.
Global fire activity was the lowest since at least 2003; however, high activity occurred in parts of North America, South
America, and Europe, with an unusually long season in Spain
and Portugal, which had their second and third driest years
on record, respectively. Devastating fires impacted British
Columbia, destroying 1.2 million hectares of timber, bush, and
grassland, due in part to the region’s driest summer on record.
In the United States, an extreme western wildfire season
burned over 4 million hectares; the total costs of $18 billion
tripled the previous U.S. annual wildfire cost record set in 1991.
Europe and the Middle East
(2017)
In 2016, the dominant greenhouse gases released into Earth’s
atmosphere—carbon dioxide, methane, and nitrous oxide—
continued to increase and reach new record highs. The 3.5 ±
0.1 ppm rise in global annual mean carbon dioxide from 2015
to 2016 was the largest annual increase observed in the 58-
year measurement record. The annual global average carbon
dioxide concentration at Earth’s surface surpassed 400 ppm
(402.9 ± 0.1 ppm) for the first time in the modern atmospheric
measurement record and in ice core records dating back as
far as 800000 years.
One of the strongest El Niño events since at least 1950 dissipated in spring, and a weak La Niña evolved later in the year.
Owing at least in part to the combination of El Niño conditions
early in the year and a long-term upward trend, Earth’s surface
observed record warmth for a third consecutive year, albeit
by a much slimmer margin than by which that record was set
in 2015. Above Earth’s surface, the annual lower troposphere
temperature was record high according to all datasets analyzed,
while the lower stratospheric temperature was record low
according to most of the in situ and satellite datasets.
Several countries, including Mexico and India, reported
record high annual temperatures while many others observed
near-record highs. A week-long heat wave at the end of April
over the northern and eastern Indian peninsula, with temperatures surpassing 44°C, contributed to a water crisis for 330
million people and to 300 fatalities.
In the Arctic the 2016 land surface temperature was 2.0°C
above the 1981–2010 average, breaking the previous record of
2007, 2011, and 2015 by 0.8°C, representing a 3.5°C increase
since the record began in 1900. The increasing temperatures
have led to decreasing Arctic sea ice extent and thickness. On
24 March, the sea ice extent at the end of the growth season
saw its lowest maximum in the 37-year satellite record, tying
with 2015 at 7.2% below the 1981–2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the
second lowest value on record, 33% lower than the 1981–2010
average. Arctic sea ice cover remains relatively young and thin,
making it vulnerable to continued extensive melt. The mass of
the Greenland Ice Sheet, which has the capacity to contribute
~7 m to sea level rise, reached a record low value. The onset
of its surface melt was the second earliest, after 2012, in the
37-year satellite record.
Sea surface temperature was record high at the global scale,
surpassing the previous record of 2015 by about 0.01°C. The
global sea surface temperature trend for the 21st centuryto-date of +0.162°C decade−1 is much higher than the longer
term 1950–2016 trend of +0.100°C decade−1. Global annual
mean sea level also reached a new record high, marking the
sixth consecutive year of increase. Global annual ocean heat
content saw a slight drop compared to the record high in 2015.
Alpine glacier retreat continued around the globe, and
preliminary data indicate that 2016 is the 37th consecutive
year of negative annual mass balance. Across the Northern
Hemisphere, snow cover for each month from February to
June was among its four least extensive in the 47-year satellite
record. Continuing a pattern below the surface, record high
temperatures at 20-m depth were measured at all permafrost
observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island.
In the Antarctic, record low monthly surface pressures were
broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high
surface pressure records for August and November were set
at several stations. During this period, record low daily and
monthly sea ice extents were observed, with the November
mean sea ice extent more than 5 standard deviations below the
1981–2010 average. These record low sea ice values contrast
sharply with the record high values observed during 2012–14.
Over the region, springtime Antarctic stratospheric ozone
depletion was less severe relative to the 1991–2006 average,
but ozone levels were still low compared to pre-1990 levels.
Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981–2010 average of 82, but
fewer than the 101 storms recorded in 2015. Three basins—the
North Atlantic, and eastern and western North Pacific—experienced above-normal activity in 2016. The Australian basin
recorded its least active season since the beginning of the
satellite era in 1970. Overall, four tropical cyclones reached
the Saffir–Simpson category 5 intensity level.
The strong El Niño at the beginning of the year that transitioned to a weak La Niña contributed to enhanced precipitation
variability around the world. Wet conditions were observed
throughout the year across southern South America, causing
repeated heavy flooding in Argentina, Paraguay, and Uruguay.
Wetter-than-usual conditions were also observed for eastern
Europe and central Asia, alleviating the drought conditions of
2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after
being plagued by drought for several years. Even so, the area
covered by drought in 2016 at the global scale was among the
largest in the post-1950 record. For each month, at least 12% of
land surfaces experienced severe drought conditions or worse,
the longest such stretch in the record. In northeastern Brazil,
drought conditions were observed for the fifth consecutive
year, making this the longest drought on record in the region.
Dry conditions were also observed in western Bolivia and Peru;
it was Bolivia’s worst drought in the past 25 years. In May, with
abnormally warm and dry conditions already prevailing over
western Canada for about a year, the human-induced Fort
McMurray wildfire burned nearly 590000 hectares and became
the costliest disaster in Canadian history, with $3 billion (U.S.
dollars) in insured losses.
Most of the dozens of essential climate variables monitored each year in this report continued to follow their long-term trends in 2014, with several setting new records. Carbon dioxide, methane, and nitrous oxide—the major greenhouse gases released into Earth’s atmosphere—once again all reached record high average atmospheric concentrations for the year. Carbon dioxide increased by 1.9 ppm to reach a globally averaged value of 397.2 ppm for 2014. Altogether, 5 major and 15 minor greenhouse gases contributed 2.94 W m–2 of direct radiative forcing, which is 36% greater than their contributions just a quarter century ago.
Accompanying the record-high greenhouse gas concentrations was nominally the highest annual global surface temperature in at least 135 years of modern record keeping, according to four independent observational analyses. The warmth was distributed widely around the globe's land areas, Europe observed its warmest year on record by a large margin, with close to two dozen countries breaking their previous national temperature records; many countries in Asia had annual temperatures among their 10 warmest on record; Africa reported above-average temperatures across most of the continent throughout 2014; Australia saw its third warmest year on record, following record heat there in 2013; Mexico had its warmest year on record; and Argentina and Uruguay each had their second warmest year on record. Eastern North America was the only major region to observe a below-average annual temperature.
But it was the oceans that drove the record global surface temperature in 2014. Although 2014 was largely ENSO-neutral, the globally averaged sea surface temperature (SST) was the highest on record. The warmth was particularly notable in the North Pacific Ocean where SST anomalies signaled a transition from a negative to positive phase of the Pacific decadal oscillation. In the winter of 2013/14, unusually warm water in the northeast Pacific was associated with elevated ocean heat content anomalies and elevated sea level in the region. Globally,
upper ocean heat content was record high for the year, reflecting the continued increase of thermal energy in the oceans, which absorb over 90% of Earth’s excess heat from greenhouse gas forcing. Owing to both ocean warming and land ice melt contributions, global mean sea level in 2014 was also record high and 67 mm greater than the 1993 annual mean, when satellite altimetry measurements began. Sea surface salinity trends over the past decade indicate that salty regions grew saltier while fresh regions became fresher, suggestive of an increased
hydrological cycle over the ocean expected with global warming. As in previous years, these patterns are reflected in 2014 subsurface salinity anomalies as well. With a now decade-long trans-basin instrument array along 26°N, the Atlantic meridional overturning circulation shows a decrease in transport of –4.2 ± 2.5 Sv decade–1.
Precipitation was quite variable across the globe. On balance, precipitation over the world’s oceans was above average, while below average across land surfaces. Drought continued in southeastern Brazil and the western United States. Heavy rain during April–June led to devastating floods in Canada’s Eastern Prairies. Above-normal summer monsoon rainfall was observed over the southern coast of West Africa, while drier conditions prevailed over the eastern Sahel. Generally, summer monsoon rainfall over eastern Africa was above normal, except in parts of western South Sudan and Ethiopia. The south Asian summer
monsoon in India was below normal, with June record dry.
Across the major tropical cyclone basins, 91 named storms were observed during 2014, above the 1981–2010 global average of 82. The Eastern/Central Pacific and South Indian Ocean basins experienced significantly above-normal activity in 2014; all other basins were either at or below normal. The 22 named storms in the Eastern/Central Pacific was the basin's most since 1992. Similar to 2013, the North Atlantic season was quieter than most years of the last two decades with respect to the number of storms, despite the absence of El Niño conditions during both years.
In higher latitudes and at higher elevations, increased warming to be visible in the decline of glacier mass balance, increasing permafrost temperatures, and a deeper thawing layer in seasonally frozen soil. In the Arctic, the 2014 temperature over land areas was the fourth highest in the 115-year period of record and snow melt occurred 20–30 days earlier than the 1998–2010 average. The Greenland Ice Sheet experienced extensive melting in summer 2014. The extent of melting was above the 1981–2010 average for 90% of the melt season, contributing to the second lowest average summer albedo over Greenland since observations began in 2000 and a record-low albedo across the ice sheet for August. On the North Slope of Alaska, new record high temperatures at 20-m depth were measured at four of five permafrost observatories.
In September, Arctic minimum sea ice extent was the sixth lowest since satellite records began in 1979. The eight lowest sea ice extents during this period have occurred in the last eight years. Conversely, in the Antarctic, sea ice extent countered its declining trend and set several new records in 2014, including record high monthly mean sea ice extent each month from April to November. On 20 September, a record large daily Antarctic sea ice extent of 20.14 × 106 km2 occurred.
The 2014 Antarctic stratospheric ozone hole was 20.9 million km2 when averaged from 7 September to 13 October, the sixth smallest on record and continuing a decrease, albeit statistically insignificant, in area since 1998.
In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events.
According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earth’s surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range.
In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new
daily maximum sea ice area of 19.57 million km2 reached on 1 October.
ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming.
Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970.
In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost.
At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series.
Large-scale climate patterns influenced temperature and weather patterns around the globe in 2011. In particu-lar, a moderate-to-strong La Niña 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 Niña. 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°C from 2010 to 2011, associ-ated with cooling influences of La Niña. 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 temper atures were anomalously cold. This led to large spring time stratospheric ozone reductions in polar latitudes in both hemispheres. Ozone concentrations in the Arctic strato-sphere 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 radia-tive 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 Niño to La Niña, 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 tem-peratures were more than 3°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 tempera-ture of -12.3°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 pres-sure on sea ice and the generally cool conditions around the Antarctic perimeter.Unauthenticated | Downloaded 05/07/21 10:23 AM UTC