Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 24

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
PL
Elementem meteorologicznym bardzo istotnym z punktu widzenia mieszkańców miast jest wiatr, wpływający m.in. na temperaturę odczuwalną, zasięg miejskiej wyspy ciepła czy stężenie zanieczyszczeń w atmosferze. Na podstawie badań przeprowadzonych w Toruniu w 2012 roku stwierdzono duże deformacje kierunku oraz zmniejszenie prędkości wiatru w stosunku do terenów podmiejskich. Najmniejsze średnie prędkości wiatru odnotowano na terenach leśnych (0,2 m·s–1 ) oraz parkowych (0,6 m·s–1 ), a największe wystąpiły na obszarze o zabudowie wielorodzinnej (1,1 m·s–1 ). Analizie poddano również modyfi kacje kierunków wiatru. Największe wystąpiły na obszarze leśnym, a najmniejsze na obszarze o zabudowie zróżnicowanej.
EN
Wind is a particularly significant meteorological element from the point of view of the residents of cities, as it affects, for example, the subjective temperature, the extent of the Urban Heat Island or the concentration of atmospheric pollution. On the basis of observations carried out in Toruń in 2012, great deformations of wind directions and reduction of its speed were found as compared to suburban areas. The lowest values of annual mean speed were recorded in forest areas (0.2 m·s–1 ) and in parks (0.6 m·s–1 ). The highest winds, on the other hand, occurred in the area of multi-apartment buildings (1.1 m·s–1 ). Modifications of wind directions were also analysed and were found to occur to the greatest extent in forest areas, and in areas of diversified land development, the least.
PL
W artykule przedstawiono zróżnicowanie przestrzenne temperatury oraz wilgotności powietrza w rejonie Kaffiøyry (NW Spitsbergen) w sezonie letnim 2014 r. Na podstawie pomiarów na stanowiskach położonych na różnych wysokościach nad poziomem morza przeanalizowano zmiany temperatury i wilgotności powietrza w pionie, obliczono pionowe gradienty tych elementów. Uzyskane wyniki odniesiono do pionowych sondaży atmosfery wykonywanych w pobliskiej stacji w Ny Ålesund. Temperatura oraz wilgotność względna powietrza wykazują znaczne zróżnicowanie przestrzenne. Relacje między stanowiskami zmieniają się z dnia na dzień w zależności od rodzaju mas powietrza oraz zachmurzenia. Stwierdzono również zmienność pionowych gradientów temperatury i wilgotności względnej powietrza w cyklu dobowym.
EN
This article presents the spatial diversity of temperature and relative humidity of the air in the area of Kaffiøyra (NW Spitsbergen). In the summer season of 2014 (21 July – 31 August), observations were carried out at 9 measurement points equipped with temperature and humidity recorders. The points were located in two terrain profiles: the mountains where the highest point was situated at 590 m a.s.l. in the Prins Heinrichfjella range and from the terminal moraines to the firn field (375 m a.s.l.) of the Waldemar Glacier. On the basis of the measurements taken at the sites situated at different absolute heights vertical changes in air temperature and humidity were analysed and lapse rate of air temperature gradients were determined. The results were referenced to vertical atmospheric soundings carried out at the nearby station in Ny Ålesund. The air over NW Spitsbergen (Ny Ålesund) demonstrated a mean vertical lapse rate of 0.61˚C/100 m at the atmospheric layer up to six or seven hundred metres. On most days normal stratification was observed, where temperature fell with height, on 3 days a ground-level air temperature inversion occurred and on 9 days a temperature inversion occurred in the free troposphere. In the area of Kaffiøyra, air temperature decreased with height from 5.5°C on the coast (KH) to 2.5°C at 590 m a.s.l. (PH2). On the Waldemar Glacier, the mean air temperature ranged from 5.0°C on the moraines (ATA) to 3.6°C on the firn field (LW2). The relationship between the sites changed on a daily basis, depending on the cloud amount, insolation and local circulation (e.g. connected with the influence of foenic wind). Averaged lapse rate in relation to the coast (KH) reached between 0.84°C/100 m (LW1-KH) and 0.39°C/100 m (KU-KH) or 0.40°C/100 m (ATA-KH). The mountain tops (PH1 and PH2) are also distinguished by their smaller lapse rate. An inversion in the vertical distribution of air temperature was also frequent and, for example, at the KT site it occurred at 33.9% of the hours and at 28.7% at ATA. On the Waldemar Glacier, inversion occurred at a frequency of 16.3% at its front (LW1) to 8.8% at its firn field (LW2). On the mountain tops, the inversion occurred at a frequency of 18% (PH2). The relative humidity of the air over Spitsbergen is high due to the prevalence of maritime air masses. According to the soundings conducted at Ny Ålesund, the humidity increased with the height, however in 13 cases a vertical inversion of relative humidity occurred – the overground air layers proved more saturated with water vapour. On Kaffiøyra, the average relative humidity of the air was 87.7% and increased up to approx. 500 m, above which it slightly dropped. This results from a high frequency of occurrence of Stratus clouds which do not reach the higher tops. The vertical gradients of relative humidity were diverse: at most sites, the relative humidity increased with the height, for example at the PH1 site, the gradient was 3.12%/100 m. A greater diversity of the relative humidity was typical of the hours around midday.
PL
W artykule przedstawiono historię badań polarnych prowadzonych w latach 1968-2015 przez pracowników Katedry Meteorologii i Klimatologii Uniwersytetu Mikołaja Kopernika w Toruniu. Omówiono i scharakteryzowano problematykę badawczą dominującą w opublikowanych w Polsce i za granicą artykułach i monografiach. Wskazano na główne obszary badawcze położone w Arktyce i Antarktyce dla których powstało najwięcej opracowań z zakresu meteorologii i klimatologii. Szczegółowo przedstawiono historię badań terenowych oraz ich rezultaty.
EN
The article presents the history of polar research conducted from 1968 to 2015 by researchers at the Department of Meteorology and Climatology at Nicolaus Copernicus University in Toruń. It discusses and characterises the predominant research issues appearing in articles and monographs published in Poland and abroad. The article also indicates the main study areas located in the Arctic and Antarctic which have been the subject of the largest number of papers in the field of meteorology and climatology. In addition, there is a detailed outline of the history of field research and its results. The researchers at the Department of Meteorology and Climatology at NCU participated in a total of 34 polar expeditions during this period, including to Iceland (1), Spitsbergen (27) and Antarctica (6) (Tab. 1, Fig. 1). They have published 371 scholarly papers in the field of meteorology, climatology, hydrology and cryology (Tab. 2, Figs. 2-4), including three post-doctoral theses (habilitations) and five doctoral theses (Tab. 4) as well as being the supervisors of 49 Master’s (magister) theses. In the last 20 years they have taken part in 16 research projects, including two international ones (Tab. 3).
PL
W opracowaniu przedstawiono zagadnienie zróżnicowania pola wilgotności powietrza w Toruniu w 2012 roku. Do tego celu wykorzystano wyniki pomiarów z 5 punktów usytuowanych w różnych częściach miasta. Wilgotność powietrza została przedstawiona poprzez dwie jej charakterystyki: wilgotność względną (%) i ciśnienie pary wodnej (hPa). Uzyskane wyniki wskazują na duże zróżnicowanie wilgotności powietrza w mieście zarówno w świetle wartości średnich rocznych, miesięcznych, jak i dobowych. W przypadku wilgotności względnej średnio w roku najmniejszą wartość zaobserwowano w centrum miasta w punkcie LO1 (75%), natomiast największą w lesie na wschodzie. Zróżnicowanie wilgotności powietrza na terenie Torunia w 2012 roku 409 miasta w punkcie LBI (82%). W przypadku ciśnienia pary wodnej średnio w roku największe wartości wystąpiły w centrum miasta (LO1) oraz obszarze leśnym (LBI) – po 9,8 hPa, natomiast najmniejsze na północy miasta w punkcie WRZ (9,4 hPa). Zbadano także wpływ sytuacji synoptycznych na zróżnicowanie wilgotności powietrza na terenie miasta. Zarówno w przypadku wilgotności względnej, jak i ciśnienia pary wodnej obserwuje się nieco większe ich zróżnicowanie na terenie miasta w czasie występowania układów antycyklonalnych w porównaniu z cyklonalnymi. Jedynie latem między stacjami LO1 (centrum miasta) i LBI (obszar leśny na wschodzie miasta) następuje odwrócenie relacji wielkości różnic ciśnienia pary wodnej przy różnych układach barycznych. Na zróżnicowanie wielkości wilgotności powietrza wpływają pozostałe elementy meteorologiczne. Problem ten zbadano na przykładzie stacji LO1 i WRZ. Znaleziono istotną statystycznie korelację wielkości różnic wilgotności względnej oraz prędkości wiatru dla wszystkich pór roku. W przypadku zachmurzenia jego wielkość jest istotnie skorelowana z różnicami ciśnienia pary wodnej, natomiast z wilgotnością względną nie wykazuje korelacji.
EN
In this article the problem of spatial diversity of the air humidity field in Toruń in 2012 is addressed. For this purpose, results of measurements taken at 5 sites located in different parts of the city were used. The air humidity is presented through its relative humidity (%) and the water vapour pressure (hPa). The obtained results indicate a substantial diversity of air humidity in the city, whether represented as mean annual, monthly or diurnal values. In the case of the relative humidity, the lowest mean value was observed in the city centre, at LO1 (75%), whereas the highest value was recorded in a wood at the LBI (82%) site, located in the east of the city. As far as the water vapour pressure is concerned, the highest annual mean values occurred in the city centre (LO1) and the woodland area (LBI) – 9.8 hPa each, whereas the lowest readings were observed at WRZ in the north of the city (9.4 hPa). The influence of the synoptic situations on the diversity of air humidity in the city was also analysed. Both the relative humidity and the water vapour pressure were found to be slightly more diversified within the city when anticyclonic pressure systems prevailed, as compared to cyclonic systems. Only in the summer, between LO1 (city centre) and LBI (woodland in the east), did the correlation reverse. The diversity of air humidity is affected by meteorological elements. The problem was studied on the basis of the observations made at the LO1 and WRZ sites. A statistically significant correlation was found in the values of the difference in relative humidity and wind speed in all seasons of the year. In the case of cloudiness, its amount is significantly correlated with the differences in the water vapour pressure, but no correlation was found of this element with the relative humidity.
PL
W artykule przedstawiono zmiany poszczególnych składowych bilansu radiacyjnego w cyklu rocznym i dobowym w Koniczynce k. Torunia w latach 2011–2012. Badania prowadzono za pomocą Net Radiometer CNR 4 fi rmy Kipp & Zonen nad powierzchnią trawiastą. W Koniczynce roczne sumy K↓ wyniosły 3901,1 MJ·m–2 w 2011 roku i 3840,1 MJ·m–2 w 2012 roku. Średnie miesięczne wartości albedo wahały się od 16 do 57%, przekraczając 80% w dniach z pokrywą śnieżną. Bilans promieniowania krótkofalowego (K*) sięgnął 3039,1 MJ·m–2 w 2011 roku i 3085,6 MJ·m–2 w 2012 roku. Wypromieniowanie długofalowe (L↑) z cieplejszej powierzchni ziemi było większe (11 431,5 MJ·m–2 w 2011 r. i 11 405,8 MJ·m–2 w 2012 r.) niż zwrotne promieniowanie długofalowe atmosfery (odpowiednio 10 032,8 i 10 050,4 MJ·m–2), stąd też bilans promieniowania długofalowego (L*) przyjął wartości ujemne (odpowiednio –1398,7 i –1355,4 MJ·m–2). Bilans radiacyjny (Q*) był ujemny w styczniu i lutym 2011 roku oraz w okresie od listopada 2011 do stycznia 2012 roku i w grudniu 2012 roku, przyjmując najmniejsze wartości w grudniu 2011 roku (–40,9 MJ·m–2). Największe wartości Q* osiągnął w czerwcu 2011 roku (386,4 MJ·m–2) i lipcu 2012 roku (341,1 MJ·m–2). W sumie w ciągu roku powierzchnia ziemi w Koniczynce otrzymała 1640,4 MJ·m–2 w 2011 roku i 1730,2 MJ·m–2 w 2012 roku. Bilans promieniowania w Koniczynce wykazuje cykliczność dobową i roczną zaburzaną przez zachmurzenie oraz parę wodną i aerozole.
EN
This article describes changes in individual components of the solar radiation balance in an annual and diurnal course at Koniczynka near Toruń in the years 2011–2012. Observations were conducted on grass-covered surfaces, using a Kipp & Zonen CNR 4 net radiometer. At Koniczynka, the annual total incoming solar radiation (K↓) amounted to 3901.1 MJ·m–2 in 2011 and 3840.1 MJ·m–2in 2012. Mean monthly values of the albedo ranged from 16 to 57% and exceeded 80% when the ground was covered by snow. The short wave radiation balance (K*) reached 3039.1 MJ·m–2 in 2011 and 3085.6 MJ·m–2 in 2012. The upward long wave terrestrial radiation (L↑) emitted from warmer surfaces was greater (11,431.5 MJ. m–2 in 2011 and 11,405.8 MJ·m–2 in 2012) than the downward long wave atmospheric radiation (10,032.8 MJ·m–2 and 10,050.4 MJ·m–2, respectively), therefore the long wave radiation balance (L*) was negative (–1398.7 MJ·m–2 and –1355.4 MJ·m–2, respectively). The net radiation balance (Q*) was negative in January and February 2011, and from November 2011 until January 2012, as well as in December 2012, with the lowest values in December 2011 (–40.9 MJ·m–2). The highest values of Q* were observed in June 2011 (386.4 MJ·m–2) and July 2012 (341.1 MJ·m–2). All in all, the ground surface at Koniczynka received 1640.4 MJ·m–2 in 2011 and 1730.2 MJ·m–2 in 2012. The net radiation balance at Koniczynka follows a diurnal and an annual cycle, disturbed by cloudiness, water vapour and aerosols.
PL
W artykule przedstawiono przebieg warunków meteorologicznych na Stacji H. Arctowskiego (Wyspa Króla Jerzego, Szetlandy Pd., Antarktyka) w 2012 roku. Pomiary prowadzono za pomocą automatycznej stacji meteorologicznej Davis Vantage Pro+ w interwale godzinnym. Przeanalizowano zmienność ciśnienia atmosferycznego, promieniowania słonecznego, temperatury i wilgotności powietrza oraz kierunku i prędkości wiatru w cyklu rocznym i dobowym. Uzyskane wyniki porównano z dłuższym okresem pomiarowym (1977-1999) oraz z równoległymi danymi z innych stacji prowadzących pomiary meteorologiczne na Wyspie Króla Jerzego.
EN
This paper presents the meteorological conditions at the Arctowski Station (King George Island, South Shetland Islands, Antarctica) in 2012. Measurements were carried out using an automatic weather station Davis Vantage Pro+. At the Arctowski Station the global solar radiation in the period from January 19 to December 31, 2012 amounted to 2985.3 MJ.m-2 (8.60 MJ.m-2.day-1). Taking into account the full year from 1 February 2012 to 31 January 2013, this totaled to 2909.6 MJ.m-2 (7.97 MJ.m-2.day-1). The highest monthly value of solar radiation occurred in December, 567.8 MJ.m-2 (18.32 MJ.m-2.day-1) and the lowest in June, 10.4 MJ.m-2 (0.35 MJ.m-2.day-1). The average annual air temperature was –1.5°C, with the highest monthly average in January (2.4°C) and lowest in June (–5.6°C). The maximum of air temperature was 9.6°C, and the minimum –17.2°C. In 2012 the average atmospheric pressure at sea level was 989.0 hPa, with a characteristic semi-annual oscillation of pressure with two minima: in summer (January 985.3 hPa) and winter (June 979.4 hPa) and two maxima: in autumn (April 996.7 hPa) and spring (September 994.9 hPa). The lowest pressure was 946.8 hPa and the highest 1020.7 hPa. At the Arctowski Station SW, NE, E and SE winds dominate in accordance with gradient of air pressure and the local orography. The average wind speed at 2 m above the ground was 4.8 ms-1, with maximum in winter (June 6.1 ms-1) and minimum in summer (December 3.1 ms-1). The maximum wind speed exceeded 40 ms-1. Relative air humidity was 83%. There is less humidity in summer (January 78%) than in winter (July, 87%). In the course of humidity indicate the day with low humidity during foehn winds. Arctowski Station area is warmer to other regions of King George Island (about 1°C in summer and 1.5°C in winter). On the King George Island and Antarctic Peninsula area occurred increase of air temperature. At the neighboring station Bellingshausen in the years 1968-2012 air temperature rise by 0.17°C/10 years.
PL
W pracy przedstawiono problem występowania susz meteorologicznych na rolniczym obszarze zlewni Strugi Toruńskiej. Analizę zmienności miesięcznych susz meteorologicznych w latach 1951-2010 przeprowadzono na podstawie danych ze stacji Zintegrowanego Monitoringu Środowiska Przyrodniczego w Koniczynce (Pojezierze Chełmińskie). Jest to rejon charakteryzujący się niewielką sumą roczną opadów - 548 mm, o bardzo dużej ich zmienności z roku na rok (od 307 mm w 1951 r. do 1050 mm w 1980 r.). W poszczególnych miesiącach zmienność opadów jest jeszcze większa (współczynnik zmienności zmienia się od 49% w marcu do 93% w czerwcu). Intensywność suszy w każdym miesiącu oceniono za pomocą wskaźnika standaryzowanego opadu SPI (Standardized Precipitation Index). W Koniczynce w badanym wieloleciu susze pojawiały się we wszystkich miesiącach roku. Stwierdzono 73 okresy suszy, które łącznie trwały 186 miesięcy, czyli przez 26% miesięcy badanego wielolecia. Najczęściej pojawiały się jednomiesięczne susze (28 razy), oraz dwu- (15 razy) i trzymiesięczne (po 13 razy). Przeciętny okres suszy trwał 2,5 miesiąca, a najdłuższy - 10 miesięcy. Najwięcej ekstremalnych susz pojawiło się w marcu, kwietniu, sierpniu i grudniu, silnych susz w lutym i we wrześniu, a umiarkowanych w sierpniu i w grudniu. Dla rolnictwa istotne znaczenie mają susze meteorologiczne w okresie wiosennym (III-V) i letnim (VI-VIII). W wieloleciu 1951-2010 trwały one łącznie 96 miesięcy, co stanowi 13% badanego okresu i powodowały opóźnienie siewu i wschodów roślin lub całkowite ich usychanie. W niektórych latach, np. w 1971, 1975, 1996, 2003 r., wczesnowiosenną suszę meteorologiczną poprzedzała dodatkowo susza w miesiącach zimowych.
EN
The paper presents the problem of meteorological droughts in an agricultural catchment of the Struga Toruńska. The analysis of monthly variation of meteorological droughts between 1951 and 2010 was based on data from the Station of Integrated Environmental Monitoring in Koniczynka (Chełmno Lakeland). The region is characterized by a small sum of annual rainfall (548 mm), and a high year-to-year variability (from 307 mm in 1951 to 1050 mm in 1980). For particular months, the variability coefficient was even higher ranging from 49% for March to 93% for June. The intensity of drought in each month was assessed using Standardized Precipitation Index (SPI). In Koniczynka, droughts were recorded in all months of the year. Seventy three periods of drought were recorded which lasted in total 186 months i.e. 26% of the study period. Most frequent were one-month droughts (28), two-month (15) and three-month (13) droughts. The average dry period lasted 2.5 months; the longest lasted 10 months. The extreme droughts appeared most often in March, April, August and December (3 cases in each), severe droughts - in February and in September (4), and moderate droughts in August and December (7). Meteorological droughts particularly important for agriculture are those in the spring (March-May) and summer (June-August) time. In the years 1951-2010 they lasted 96 months in total, which represented 13% of the study period (March-August). They caused delayed sowing and sprouting of plants or complete plant wilting. Moreover, in some years (1971, 1975, 1996, 2003) meteorological drought in the winter months preceded the early spring drought.
EN
This paper presents the outline, methodology, and the state of the realization of a research project. Its goal is to study the influence of environmental, dynamic, and anthropogenic factors on meteorological and biometeorological conditions. It is also planned to work out a map of Toruń topoclimates. The research was performed for over a year on the basis of a network of 26 measurement points selected in different places in Toruń and its neighbourhood with automatic registration of basic meteorological elements and thermal imageries from Terra ASTER satellite. The environment geographic information system created in ArcGIS is used for interpolation of individual meteorological elements and for distribution of biometeorological indices. Various spatial data were used such as land cover, land use, localization and height of buildings, digital elevation model (DEM), and present-day colour orthophotomap. Project results relating to the variability of Toruń bioclimatic conditions may be used for organization of tourism and recreation, and the created map of topoclimates for spatial planning and further development of the city.
PL
Praca prezentuje założenia, metodykę oraz stan realizacji projektu naukowo-badawczego, którego celem jest zbadanie wpływu czynników środowiskowych, dynamicznych i antropogenicznych na warunki meteorologiczne i biometeorologiczne wraz z planowanym opracowaniem mapy topoklimatów miasta Torunia. Badania prowadzone są od ponad roku w oparciu o założoną w wybranych miejscach Torunia i okolic sieć 26 punktów pomiarowych z automatyczną rejestracją podstawowych elementów meteorologicznych oraz docelowo satelitarne obrazy termalne pozyskane z satelity Terra ASTER. Zbudowany w środowisku ArcGIS system informacji geograficznej (GIS) wykorzystywany jest do interpolacji rozkładu poszczególnych elementów meteorologicznych oraz rozkładu wskaźników biometeorologicznych. Do tego systemu pozyskano i wprowadzono już wiele danych przestrzennych, jak pokrycie/użytkowanie terenu, lokalizacja i wysokość budynków, model wysokościowy terenu (DEM) oraz aktualną barwną ortofotomapę. Uzyskane w projekcie wyniki dotyczące zmienności warunków bioklimatycznych Torunia będą mogły być wykorzystane w organizacji turystyki i rekreacji, a utworzona mapa topoklimatów w planowaniu przestrzennym i dalszym rozwoju miasta.
PL
W artykule porównano wyniki rejestracji usłonecznienia heliografem Campbella-Stokesa (HCS) i czujnikiem świecenia Słońca DSU12 (DSU12) w Koniczynce k. Torunia w latach 2006-2010. W tym okresie średnie roczne wartości usłonecznienia wyniosły 1644,1 godz. (HCS) i 1699,1 godz. (DSU12). Różnica sięgnęła 55,0 godz., co stanowi 3,3% wartości zmierzonej HCS. Największe różnice występują w ciepłej połowie roku, kiedy to DSU12 rejestruje większe usłonecznienie, np. w czerwcu średnio o 24,1 godz., natomiast w chłodnej połowie roku usłonecznienie zarejestrowane przez DSU12 było mniejsze, np. w listopadzie o 9,4 godz. W przeliczeniu na jeden dzień różnice te sięgają od -0,31 godz. w listopadzie do 0,80 godz. w czerwcu. W wartościach względnych najmniejsze różnice występują w marcu (1,7%), kwietniu (1,5%) i wrześniu (3,7%). Zdecydowanie większe różnice, sięgające - 44,7% miesięcznego usłonecznienia, występują w grudniu. Przeprowadzona analiza wykazała wyraźną zmienność sezonową różnic usłonecznienia między porównywanymi przyrządami. Dlatego też przy przeliczaniu miesięcznych sum usłonecznienia celowe jest stosowanie odrębnych równań regresji do każdego z miesięcy. W tym celu, ze względu na indywidualne cechy każdego przyrządu, celowe jest prowadzenie kilkuletnich synchronicznych pomiarów za pomocą przyrządów tradycyjnych i automatycznych.
EN
In the article are compared the results of recording sunshine duration using a Campbell-Stokes heliograph (HCS) and a DSU12 sunshine duration sensor (DSU12) carried out at Koniczynka near Toruń in the years of 2006-2010. In the analysed period the annual mean values of sunshine duration were recorded as 1644.1 hours (HCS) and 1699.1 hours (DSU12). The difference reached 55 hours, i.e. 3.3%. The biggest differences occurred in the warm half of the year, when the DSU12 recorded more sunshine, e.g. on average 24.1 hours more in June. However in the cold months of the year the sunshine duration recorded using the sensor was shorter, e.g. at 9.4 hours in November. The average differences per day ranged from -0.31 hours in November to +0.80 hours in June. In relative values, the smallest differences occurred in March (1.7%), April (1.5%) and September (3.7%). Considerably larger differences, reaching -44.7% of monthly sunshine duration, were observed in December. The comparison demonstrated a distinct seasonal variability of the differences in sunshine duration between compared recorders. Therefore, it seems reasonable to apply separate regression equations for each month to determine monthly sums of sunshine duration. To this end, due to specific characteristics of each instrument, it is advisable to keep parallel records for several years using traditional and automatic recorders.
PL
Celem niniejszego opracowania jest porównanie średniej dobowej prędkości wiatru zmierzonej różnymi przyrządami oraz obliczonej różnymi metodami w sezonie letnim w warunkach klimatu polarnego. Material źródłowy stanowiły wyniki pomiarów prędkości wiatru na Kaffi0yrze (Ziemia Oskara II) na Spitsbergenie wykonywanych w sezonach letnich (od 21 lipca do 31 sierpnia) w latach 2005-2010. Pomiary prędkości wiatru prowadzono za pomocą automatycznej stacji meteorologicznej firmy Davis oraz anemometrem ręcznym Windmaster II. Pomiary automatyczną stacją meteorologiczną dokonywane były z krokiem czasowym co 10 minut (144 razy na dobę), natomiast anemometrem Windmaster II 4 razy na dobę (00, 06, 12, 18 UTC, tj. 01, 07, 13, 19 LMT). W opracowaniu oceniono dokładność obliczania wartości średniej dobowej prędkości wiatru z 3, 4, 8, 24, 48 i 144 terminów w ciągu doby. Przeprowadzona analiza dowodzi, obliczanie średniej dobowej prędkości wiatru z 8, 24, 48 i 144 terminów w ciągu doby (wg danych z automatycznej stacji meteorologicznej) można porównywać bez szkody dla wartości średniej. W opracowaniu wykaŹzano m.in., że, przeciętny błąd estymacji średniej dobowej obliczonej z 48, 24 i 8 terminów w porównaniu do średniej liczonej ze 144 pomiarów jest równy 0,00 ms-1. Pomiary anemometrem Windmaster II w stosunku do pomiarów automatycznych dają natomiast wyniki zawyżone (średnio o ok. 0,4 ms-1).
EN
The purpose of this article is to compare the mean daily wind speed in the polar summer season, measured using various instruments and calculated using various methods. The sources of informaŹtion were the results of wind speed measurements taken in the Kaffi0yra region of Spitsbergen (Oscar II Land) in the summer period (21 July - 31 August) of 2005 - 2010. The measurements were carried out using a Davis automatic weather station and a Windmaster II anemometer. The measurements obtained from the automatic weather station were taken at 10-minute intervals (144 times per day), whereas those from the Windmaster II unit - four times per day (at 00:00, 06:00, 12:00 and 18:00 UTC, or 01:00, 07:00, 13:00 and 19:00 LMT). This study evaluates the accuracy of the calculated mean daily wind speed from 3, 4, 8, 24, 48 and 144 intervals throughout the day. An analysis proved that the determination of a mean daily wind speed using the measurements from 8, 24, 48 and 144 intervals per day (according to the data from the automatic weather station) can be compared without affecting the mean value itself. This study demonstrates e.g. that the average error of estimation of a mean daily value calculated from 48, 24 and 8 intervals is 0.00 ms-1 as compared to an average value determined using all 144 intervals. However, the measurements taken by means of the Windmaster II anemometer give overstated results in comparison to the automatic measurements (at about 0.4 ms-1 on average).
PL
W artykule przedstawiono zróżnicowanie wilgotności względnej powietrza oraz opadów atmosferycznych w rejonie Forlandsundet (NW Spitsbergen) w sezonie letnim (21 VII - 31 VIII) 2010 roku. Do analizy wzięto cogodzinne dane wilgotności względnej (z 18 stanowisk) oraz sumy opadów atmosferycznych z okresów 1-3 dniowych (z 11 stanowisk). Dla obydwu badanych elementów meteorologicznych stwierdzono znaczne przestrzenne zróżnicowanie ich wartości uwarunkowane rodzajem podłoża, wysokością nad poziom morza, odległością od morza, ekspozycją oraz lokalną cyrkulacją atmosferyczną. Zbadano wpływ cyrkulacji atmosferycznej na wartości wilgotności względnej i opadów atmosferycznych korzystając z kalendarza typów cyrkulacji dla Spitsbergenu.
EN
In the paper some main results concerning spatial differentiation of relative humidity and precipitation in the Forlandsundet region (NW Spitsbergen) in summer season (21 VII - 31 VIII) of 2010 are presented (Table 1, Figs 1-2). For analysis hourly data from 18 and 11 sites, respectively for relative humidity and precipitation have been used. Relative humidity was measured using automatic weather stations Davis Ventage Pro2 and MadgeTech sensors. On the other hand, for measurements of precipitation Hellmanns' ombrometers and automatic weather stations Davis Ventage Pro2 have been utilised. Large spatial differences of relative humidity and precipitation noted in the study area were influenced by different factors, e.g. character of ground, altitude above sea level, distance from the sea coast, exposition to the sun and incoming air masses, and local atmospheric circulation. Highest mean values of relative humidity (94.6%) occurred at the site surrounded by the sea (Sarstangen Peninsula, SAT), while the lowest one (86.4%) at the site located 200 m from the Waldemar Glacier termini (ATA) (Table 3, Fig. 3). The first half of the day saw highest values of relative humidity than the second one (Fig. 4). The reason of this may be explained by the opposite daily course of air temperature. Daily courses are getting more and more clear in line with decreasing value of cloudi-ness (Fig. 5). In the Forlandsunet region most frequent were air masses which can be described as humid and very humid. Days with moderate dry and dry air were noted very rarely (Fig. 6). Relative humidity shows usually very high and statistically significant correlation between data from the analysed sites (Table 3). Weak and not statistically significant correlations (r < 0.3) were calculated only between the following pair of sites SAT-PH2 and SJ1-PH2. In the summer 2010 the lowest total of precipitation (8.5 mm) in the KH station, out of all Toruń Polar Expeditions since 1975, have been observed (Table 4). In the firn part of the Waldemar Glacier seasonal total of precipitation was 3-4 times greater than in sites located on coastal plains. In the Kaffioyra Plain and Waldemar Glacier region vertical lapse rate was twofold greater between KH and LW1 than between KH and LW2 (14.7 and 7.7 mm/100m, respectively). In the entire study area, highest summer total of precipitation occurred in the middle part of the Prins Karls Forland island. Relationships between atmospheric circulation and relative humidity as well as precipitation were investigated using data from the KH station and calendar of daily synoptic types for Spitsbergen constructed by Tadeusz Niedźwiedź (Table 5). The most humid conditions in the summer 2010 were observed during inflow of air masses from south-western direction (6.6% above summer mean), while most dry air (-9.7%) - from the north-eastern direction. Similar relationships have been found for precipitation. Analysis of relationships occurring between direction of winds and relative humidity data confirms also the above results. Highest values of relative humidity (>90%) were observed during winds inflowing from the southern sector, while the lowest ones - from the north-eastern direction (Fig. 7).
PL
W artykule przedstawiono wyniki rejestracji składowych bilansu promieniowania na 3 stanowiskach: Kaffioyra-Heggodden (KH), Lodowiec Waldemara-czoło (LW1) i Lodowiec Waldemara-pole firnowe (NW Spitsbergen) w okresie od 16.07 do 31.08.2010 r. Pomiary prowadzono przy pomocy Radiometru CNR4 firmy Kipp&Zonen. Co minutę rejestrowano natężenie promieniowania słonecznego K?, promieniowania odbitego (K?), promieniowania ziemi (L?) i promieniowania zwrotnego atmosfery (L?). Na tej podstawie obliczono bilans radiacyjny (Q*), składający się z bilansu krótkofalowego (K*) i długofalowego (L*). Stwierdzono niewielkie różnice pomiędzy stanowiskami KH i LW2 założonymi na podłożu morenowym. Najmniej korzystny Q* wystąpił na LW2 nad powierzchnią śnieżno-lodowcową charakteryzującą się wysokim albedo. W artykule zbadano zróżnicowanie przestrzenne składowych bilansu radiacyjnego z dnia na dzień oraz w cyklu dobowym.
EN
Measurements of radiation balance (Q*) were carried out in the Kaffioyra region (NW Spitsbergen) between 16 July and 31 August 2010 at three stations with different surfaces: KH on the glacial moraine of the Aavatsmark (11.5 m a.s.l.), LW1 - on the terminal moraine of the Waldemar Glacier (130 m a.s.l.), and LW2 - on the firn field of the Waldemar Glacier (375 m a.s.l.) - Fig. 1. A Kipp&Zonen CNR 4 Net Radiometer was used to register - minute by minute - the short wave radiation balance (K*), which is the difference between incoming solar radiation K? and reflected solar radiation (K?), and the long wave radiation balance (L*), which is the difference between downward long wave atmospheric radiation (L?) and upward long wave radiation (L?) - Table 1. In the studied period the maximum intensity of incoming solar radiation reached 709.4 W.m-2 at KH, 882.1 W.m-2 at LW1 and 836.2 W.m-2 at LW2. The mean diurnal sums of incoming solar radiation ranged from 11.04 MJ.m-2 at KH to 10.46 MJ.m-2 at LW1 and 10.60 MJ.m-2 at LW2 (Table 2, Fig. 2). The surface albedo varied, reaching between 13% (LW1) and 15% (KH) on the moraines, and up to 61% (LW2) on the firn field (Table 2, Fig. 3). Thus the lowest value of short wave radiation balance, +4.31 MJ.m-2, was registered at LW2, whereas it was doubled on the moraines: KH +9.50 MJ.m-2 and LW1 +9.09 MJ.m-2 (Table 4, Fig. 4). The flux of downward long wave atmospheric radiation coming from the atmosphere does not reveal any significant differences between individual stations: KH: 27.26 MJ.m-2, LW1: 27.47 MJ.m-2 and LW2 - 27.37 MJ.m-2 in 24h (Table 3). The Earth's surface (upward long wave radiation) was losing, on average: 30.31 MJ.m-2, 29.88 MJ.m-2 and 30.10 MJ.m-2, respectively, and the mean daily values of long wave radiation balance were negative: KH -3.05 MJ.m-2, LW1 -2.42 MJ.m-2 and LW2 -2.73 MJ.m-2. The surface radiation balance (Q*) was the most favourable on moraine bases: LW1 +6.67 MJ.m-2, KH +6.45 MJ.m-2, whereas the snow-covered firn field received the smallest amount of energy: LW2 +1.58 MJ.m-2 (Table 4, Fig. 5). In spite of the polar day, the diurnal cycle of the radiation balance components appears symmetrical with regard to the solar noon, related to the elevation of the sun over the horizon and the temperature of the surface and of the atmosphere. The flux of incoming solar radiation reached its peaks during midday hours with the following mean values: KH: 278.7 W.m-2, LW1: 275.9 W.m-2, and LW2: 295.2 W.m-2 (Fig. 6). At the time of lower culmination of the sun the values of K* were falling to zero. The balance of long wave radiation was negative and reached its highest values around midday hours (KH -50.0 MJ.m-2, LW1 -40.1 MJ.m-2 and LW2 -47.5 MJ.m-2). Q* was the highest in midday hours, when it was 2.5 times higher for moraine bases (KH +194.8 MJ.m-2 and LW1 +201.5 MJ.m-2) than for snow and glacial surfaces (LW2 +79.1 MJ.m-2). At low elevation of the sun Q* became negative: KH -6.8 MJ.m-2, LW1 -5.4 MJ.m-2 and LW2 -19.4 MJ.m-2. On individual days the diurnal cycle of the components of Q* was affected not only by the elevation of the sun, but also by the atmospheric state and the presence of clouds, in particular. For example, on 27 and 28 July 2010 a different weather types occurred (Table 5, Fig. 7). On the first day the sky was completely overcast with St and Sc clouds and no sunshine was observed. On the following day it cleared up with partial cloudiness (Cu, Ac, Ci), and the sunshine duration reached 16.2 h. On 27 July a slight influx of incoming solar radiation was registered (mean intensity 68.6 W.m-2, diurnal sum 5.92 MJ.m-2), K* was 5.14 MJ.m-2, and L* -0.84 MJ.m-2 due to the total cloudiness, which supported substantial downward atmospheric radiation (downward long wave atmospheric radiation 339.3 W.m-2). On the other hand, on 28 July, when the amount of cloudi-ness was moderate, the maximum intensity of incoming solar radiation was 668.7 W.m-2. In 24 hours the total radiation that reached the surface amounted to 22.04 MJ.m-2, and K* increased to 18.90 MJ.m-2. L* was negative (-5.26 MJ.m-2) due to substantial radial emittance of the ground (upward long wave radiation 352,0 W.m-2) and some downward atmospheric radiation (downward long wave atmospheric radiation 291.1 W.m-2). However, the overall radiation balance was three times higher than on 27 July and amounted to 13.65 MJ.m-2. In the studied period, the individual components of Q* were decreasing in value, as a result of the lower and lower elevation of the sun over the horizon and the ending of the polar day.
PL
W artykule przedstawiono podsumowanie wyników badań dotyczących zmian temperatury gruntu w otoczeniu Stacji Polarnej UMK na Kaffioyrze (NW Spitsbergen) w sezonie letnim. Do analizy wzięto dane pomiarowe z 5 głębokości (1, 5, 10, 20 i 50 cm) z 3 różnych ekotopów (plaża, morena i tundra) wykonane w trakcie 17 dotychczasowych wypraw polarnych zorganizowanych przez Instytut Geografii UMK w różnych latach okresu 1975-2009. W celu uzyskania pełnej porównywalności wyników wybrano okres 21.07-31.08, dla którego dostępne są kompletne dane dla niemal wszystkich sezonów letnich analizowanych w artykule. Serie temperatury gruntu na wszystkich stanowiskach i poziomach są ze sobą bardzo silnie skorelowane. Wyraźnie największy wpływ na zmierzone wartości temperatury gruntu w całej badanej warstwie wywiera tempe-ratura powietrza (współczynniki korelacji wahają się od 0,6 do 0,86). Inne elementy meteorologiczne takie jak prędkość wiatru, zachmurzenie i usłonecznienie również w sposób istotny wpływają na temperaturę gruntu, ale głównie w warstwie 0-20 cm (współczynniki korelacji wahają się od 0,15 do 0,28). Istotny statystycznie, chociaż ilościowo bardzo niewielki, wpływ na temperaturę gruntu w warstwie do 20 cm ma także opad atmosferyczny.
EN
In the present paper a comprehensive synthesis of ground temperature changes on the Kaffiřyra Plain (NW Spitsbergen) in the summer season (21st July to 31st August) from 1975 to 2009 is described. This has been done with two main aims in mind: i) to examine the influence of different ecotypes on ground temperature values in the layer 1-50 cm, and ii) to examine long-term changes of ground temperature. The highest values of long-term average ground temperature in the summer season have been observed between 20th and 25th July. After this period a gradual decrease in ground temperature is observed (Table 2, Fig. 3). One clear cold singularity can be distinguished here occurring at the end of July and start of August which is connected with a significant decrease in air temperature observed very often during this time. In the period 1978-2009 the warmest ground in the entire analysed layer was observed at the ‘Moraine’ site (6.2°C), and the coldest was at the ‘Tundra’ site (5.1°C) – Table 3, Fig. 4. However, in the shallowest layer (up to 1 cm) markedly the warmest site was the beach, while the coldest was at a depth of 50 cm (Fig. 4). The reason for the large decrease of temperature in this layer was that this was where the permafrost roof was at its shallowest. As a consequence of this temperature behaviour in the layer, the ‘Beach’ site shows the greatest lapse rate of ground temperature (-0.78°C/10 cm) (Table 4). In the warmest summer seasons a greater range of ground temperature in the daily cycle is observed than in the coldest ones, which is very clearly seen, in particular in the layer from surface up to 20 cm (Fig. 5). In the study period a significant increase in ground temperature in the layer 1-20 cm was observed starting in 1998, while at a depth of 50 cm this rise can be seen from 2005 onward (Fig. 6). Very high and statistically significant correlation have been found between series of daily ground temperature taken from all sites and all measurement depths (Table 5). Air temperature is a meteorological variable, which has the greatest influence on the values of ground temperature. Correlation coefficients between series of its daily values and series of average daily ground temperature in all analysed depths at the ‘Beach’ site oscillate from 0.6 to 0.86 (Table 6, Fig. 7). Important factors controlling values of ground temperature in the layer 0-20 cm are also wind velocity, cloudiness and sunshine duration (correlation coefficients oscillate between 0.15 and 0.28).
PL
W artykule przedstawiono zróżnicowanie temperatury i wilgotności względnej powietrza oraz kierunku i prędkości wiatru w rejonie Kaffioyry (NW Spitsbergen) w sezonach letnich 2005-2009. Na podstawie pomiarów w 8 punktach stwierdzono znaczne różnice topoklimatyczne uwarunkowane rodzajem podłoża, wyso-kością nad poziom morza, odległością od morza, ekspozycją oraz lokalną cyrkulacją atmosferyczną. W rejonie Kaffioyry często występują sytuacje inwersyjne, związane nie tylko ze stratyfikacją termiczno-wilgotnościową napływających mas powietrza, ale również oddziaływaniem czynników lokalnych. Zróżnicowanie topoklima-tyczne zmienia się w zależności od stopnia zachmurzenia i pory doby oraz w czasie formowania się wiatrów lokalnych (wiatry lodowcowe i fenowe).
EN
The paper presents the spatial differentiation of the meteorological conditions in the summer seasons in the Kaffiřyra in the period 2005-2009. The meteorological measurement points (4 automatic weather stations and 4 electronic devices measuring temperature and humidity, 2 m a.g.l.) were located on the Kaffiřyra Plain (KH) on the Waldemar Glacier area (ATA, LW1, LW2) and on the mountains: Kuven (KU), Grĺfjellet (GF) and Prins Heinrichfjella (PH1, PH2). The analysed five seasons had changeable weather conditions dependent on types of synoptic situations. The highest air temperatures were recorded on the coast (KH 5.8°C) and on the marginal zone of the Waldemar Glacier (ATA 5.1°C). On the glaciated area air temperature is decreasing with the altitude (LW2 2.9°C). The largest temperature lapse-rate is recorded at the transitional area between the glacier and its marginal zone. Growing altitude lowers air temperature on the mountain ridges (GF 4.0°C, PH2 3.6°C), but temperature inversions are recorded quite frequently in the region. Relative air humidity is high due to low temperature and large frequency of occurrence of maritime air masses. The highest mean relative air humidity was recorded on the coast (KH 88%) and on the firn field of the Waldemar Glacier (LW2 84%) as well as on the mountain ridges (PH2 92%). The course of the relative humidity is significantly influenced by foehn winds. Wind directions and velocity in the study area are strongly dependent on the synoptic situation and influence of local factors, mainly orography (foehn winds). Wind regime in the Waldemar Glacier significantly differs from that observed in the Kaffiřyra (here the tunnel effect is observed as a consequence of the narrow Forlandsundet, presences to the abovementioned plain), mainly due to katabatic winds occurrence.
PL
W opracowaniu przedstawiono zróżnicowanie warunków opadowych w rejonie Kaffioyry (NW Spitsbergen) w sezonie letnim na podstawie danych z lat 1980-2008. Zbadano wpływ cyrkulacji atmosferycznej i warunków lokalnych na opady atmosferyczne. Uzyskane wyniki porównano ze stacją Ny-Alesund.
EN
Precipitation in the Arctic, including Spitsbergen, is very important for both the biosphere and for the mass balance of glaciers. Our knowledge about its values inside Arctic islands is limited because almost all meteorological stations are located on tundra below 200 m a.s.l. Therefore any information about precipitation conditions occurring on glaciated and non-glaciated areas lying in the inner parts of Spitsbergen is very valuable. In this paper we present results of precipitation measurements carried out in north-western Spitsbergen (the Kaffioyra region and the Ny Alesund station) in selected summer seasons during the period 1980-2008. Precipitation measurements in the Kaffioyra region have been done during Toruń Polar Expeditions in three stations (base station – Kaffioyra-Heggodden (KH) and two glacier stations located in the lower part (LW1) and upper part (LW2) (see Figure 1 and Table 1). Data for the Ny Alesund (NA) station were obtained from the Norwegian Meteorological Institute. In the KH and NA stations measurements were recorded every day, while in LW1 and LW2 they were generally taken every 1-2 days. Results of precipitation conditions are presented for a common period of observations, i. e. for 21st July-31st August. The influence of atmospheric circulation on precipitation was investigated using the catalogue of circulation types constructed by Niedźwiedź (2009). In the summer season precipitation is greater at the end of the study period, than at the beginning. Year-to-year variability of summer precipitation totals is very large. For example, in KH, the highest precipitation (122.5 mm) occurred in 1997, while the lowest (12.3 mm) was in 2007 (Table 2). Also, the frequency of daily precipitation (.0.1 mm) is significantly greater in most wet summer (61.9%) than in most dry summer (28.6%) (see Table 3). Daily precipitation of .10 mm is rare in the KH station and occurred in only 4 out of the 12 summer seasons. It is well known that precipitation is greater in the inner parts of Spitsbergen than in tundra areas. Less is known, however, about the magnitudes of these differences. For the Kaffioyra region precipi-tation observations are available for 9 summer seasons (Tables 5 and 6). From these Tables and Figure 2 it is clear that precipitation on glaciers is almost always greater than in tundra. On average, summer precipitation totals are greater in LW1 and LW2 than in KH by 21.5 and 35.1 mm, respectively. The greatest differences occurred in 1980, while the lowest were in 2007, when even in LW1 precipitation was lower than in KH (Table 5, Figure 3). Lapse rates of precipitation in the Kaffioyra region are greatest between tundra and glaciated areas (oscillating between 13.2mm/100m and 18.5mm/100m between KH and LW2 and KH and LW1, respectively (Table 7)). On the other hand, this lapse rate between stations LW1 and LW2 is the lowest (only 10.7 mm/100 m). Correlation coefficients of 10-day precipitation totals between the meteorological stations in the Kaffioyra region are very high and exceed 0.9. The greatest precipitation in the Kaffioyra region occurred during the inflow of air masses from the southern sector (Table 8, Fig. 7).
PL
W artykule przedstawiono zmienność przestrzenną przebiegu rocznego ciśnienia atmosferycznego na Antarktydzie. Stwierdzono dwa typy przebiegów rocznych ciśnienia. Na wybrzeżu występuje przebieg charaktery-zujący się półroczną oscylacją, z maksymalnymi wartościami w sezonie letnim i zimowym oraz najniższymi w przejścio-wych porach roku. We wnętrzu kontynentu najwyższe ciśnienie występuje latem, a najniższe w chłodnej połowie roku. Największe amplitudy roczne ciśnienia występują we wnętrzu kontynentu. W ostatnich dwóch dekadach XX wieku zaznaczyły się istotne zmiany w przebiegu rocznym ciśnienia atmosferycznego.
EN
At the polar latitudes of the Southern Hemisphere a circulation cell functions which is connected with the strong baric wedge feature of the atmosphere occurring between the Antarctic anticyclone and a very deep circumpolar trough by the Antarctic coastline. The circulation system in the Antarctic region shows seasonal variability called Southern Annular Mode (SAM). In the cold season the tropospheric exchange of air masses strengthens due to the increase of the katabatic winds? speed. The relocation of air masses from over Antarctica to its peripheries has an influence on the annual course of the atmospheric pressure. In the elaboration mean monthly air pressure values were taken into account from 106 Antarctic stations from the beginning of measurements to 2000. On the basis of these data the mean annual course of the atmospheric pressure has been counted as well as the yearly pressure range. Annual courses from two periods: 1958-1980 and 1981-2000 were also compared. Over the Antarctic the annual course of the atmospheric pressure is complex. At the costal part of the continent there are two maxima (in summer and in winter) and two minima in the transient seasons. This course is called semi-annual oscillation (SAO) in the literature. However this phenomenon shows certain regional specifics. On the Antarctic Peninsula and South Orkney Islands the winter maximum is more distinct, while minima are shifted to February and November. In the inland the winter maximum decreases with the distance from the coast and at stations situated in the highest parts of the glacial plateau the highest pressure values occur in summer and distinctly lower ones in winter. At some inland stations a slight increase of the pressure can be observed in the middle of winter what refers to the thermal coreless winters occurring frequently in this region. The annual range of the atmospheric pressure decreases from the coast (15-7 hPa) to the interior of the continent, where it reaches values above 20 hPa. During the last two decades of the 20th century significant changes took place in the annual courses of the pressure in comparison to the years 1958-1980. On the South Orkney Islands and the Antarctic Peninsula the pressure increased in summer and in autumn, while in winter distinctly decreased. At the remaining part of the Antarctic coast pressure decrease occurred in every seasons, and in the Weddell Sea region the autumn and spring minimum significantly deepened. At the majority of the stations the annual amplitudes of the atmospheric pressure decreased after 1980. These changes contributed to the disturbances in the functioning of the Antarctic climate system. On the Antarctic Peninsula the air temperature increased, while at many stations in the Eastern Antarctic considerable cooling occurred.
17
EN
Diurnal air temperature ranges (DTR) have been counted based on the monthly mean values of the daily maximal and minimal air temperature from 23 Antarctic stations. DTR shows a considerable spatial differentiation on the Antarctic. The lowest DTR values (4-6°C) occur along the western coast of the Antarctic Peninsula and on the subantarctic islands. At the remaining coast of Antarctica the mean DTR vary from 6-7°C to 10°C at the stations situated on higher geographical latitude. In the Antarctic inlands the largest DTR values occur at the highest parts of glacier plateau (8-9°C), while on the South Pole they are distinctly smaller (6°C). In the annual course of DTR the following types have been distinguished: oceanic type at the western coast of the Antarctic Peninsula with small DTR in summer (2-4°C) and twice higher in winter; oceanic-continental type at the coast of Eastern Antarctic with large DTR during the whole year; continental-oceanic type with high DTR in summer and still higher (up to 13°C) in winter occurring at Western Antarctic and in the Weddell Sea basin; continental type characteristic for the interior of the continent with the highest DTR in summer (11-12°C) and smaller in winter; polar type with small DTR in summer (to 3°C) and considerable higher in winter (7-8°C). A decrease of DTR occurred on the Antarctic in regions characterized by increasing temperature in the second half of the 20th century, especially on the western coast of the Antarctic Peninsula, on the coast of Ross Sea and on the Queen Maud Land. The decrease in the DTR values was connected with the quicker increase of daily minimal air temperatures. On the other hand, in the regions where cooling was noted the DTR values increase (inlands of Eastern Antarctic and South Pole, and the Weddell Sea basin), mainly due to the fall in daily minimal air temperatures.
EN
The progressive increase in the concentration of greenhouse gases in the atmosphere in consequence leads to the rise of the global air temperature. According to the III Report of IPCC (2001) from 1880 the mean temperature on the Earth has grown by 0.6°C ą0.2°C. The reaction of polar regions to the greenhouse effect is unknown. The Antarctic climate shows a considerably greater variability in comparison with the lower latitudes of the Southern Hemisphere. This is conditioned by interactions between the atmospheric circulation, the ocean, and the cryosphere. According to the scenarios of global greenhouse effect the temperature at the polar regions should grow by 3°C in summer and 4-5°C in winter. However, these model researches are not confirmed in reality. This shows that our knowledge concerning the functioning of climate system of the polar regions is insufficient. In the paper we have used monthly mean air temperature values for 21 stations being in operation on the Antarctic in the years 1958-2000 and for 34 stations making observations in the years 1981-2000. After checking the homogeneity of the series by the Alexandersson?s (1986) test we have counted the trends of air temperature. The average trend for annual and seasonal values were expressed by temperature change per 10 years. In the years 1958-2000 on the Antarctic the trend of the mean annual values of the air temperature shows great spatial differentiation. These differences are connected with the radiation balance depending on the variability of cloudiness and the albedo of the surface, and on the transformation of pressure fields and changes of the atmospheric circulation. Statistically significant (on 0.95 significance level) air temperature increase occurred on the western coast of the Antarctic Peninsula (for example Faraday 0.67°C/10 years) and at the stations Belgrano and McMurdo. A negative air temperature trend occurred on the South Pole (-0.21°C/10 years) and on the Droning Maud Land. The temperature changes in the region of the Antarctic Peninsula are correlated with the extension and surface of sea ice, especially in winter. There are considerable differences of air temperature trends on the Antarctic between the periods 1958-1980 and 1981-2000. The period 1958-1980 is characterized by an increase of air temperature, especially on the shore of continent (Casey 0.84°C/10 years, Faraday 0.76°C/10 years, Halley 0.69°C/10 years). The interior of the continent is distinguished by stability of weather conditions. Year-to-year temperature changes are smaller, then at the coast (the trend at the Amundsen-Scott station average 0.26°C/10 years). During the last years (1981-2000) significant changes took place in the tendency of air temperature on the Antarctic. In many regions of the Antarctic cooling began, on the cost of East Antarctica the temperature decreases, on the coasts of the Wilkes Land (Casey -0.82°C/10 years) and the Weddell Sea (Halley -1.13?C/10 years, Larsen Ice -0.89°C/10 years), especially in the autumn-winter period. In the interior of the continent also lower and lower temperatures occurred (Amundsen-Scott -0.42°C/10 years, Dome C -0.71°C/10 years). The cooling can be observed in all seasons, but it is the greatest in summer and autumn, when the decrease of solar radiation was observed in connection with the growing cloudiness. Vostok situated at the highest parts of ice dome does not show statistically significant trend. An increase of the temperature was observed in the interior of West Antarctica (Byrd 0.37°C/10 years). The warming rate of the climate became weaker on the Antarctic Peninsula (Faraday 0.56°C/10 years). The largest temperature changes occurred in the autumn-winter season when in the Antarctic Peninsula region the temperature increased, while in the interior and at the coast of East Antarctica considerably fell. Climate changes during the last 20 years of the 20th century showed the weakening of the warming rate on the Antarctic Peninsula and distinct cooling on the East Antarctica. The lack of warming, or even cooling, on the East Antarctica, is favourable to maintain the present climate system in this region. The increasing air temperature on the West Antarctic, especially on the Antarctic Peninsula caused many natural consequences. The ablation of glaciers clearly intensified, deglaciation takes place, glaciers retreat. The environmental changes lead to disturbances in the functioning of the Antarctic ecosystem.
19
EN
On the Antarctic the annual course of air temperature shows a considerable spatial differentiation. Over the inland the course of temperature during the year is conditioned by insolation-radiational factors. On the coast the role of circulation factors connected with the advection of air masses from above the ocean or from the interior of the continent. In the paper mean monthly air temperatures from 56 stations making standard meteorological observations and from 38 automatic weather stations (AWS) have been used. On the Antarctic there types of annual air temperature courses can be distinguished: Oceanic - characterised by positive air temperatures in the summer season with the highest temperatures in February and by mild temperatures in the winter months (to -10°C). As a result of the ocean influence spring is considerable colder then autumn. The annual amplitudes are small (to 10-15°C). This type occurs on the western coast of the Antarctic Peninsula and on the subantarctic islands. Continental - with very low air temperatures. The warmest month is December with temperatures below -30°C in the interior of the continent. In winter the lowest mean monthly temperatures reach -70°C. The temperature frequently increases in the middle of winter; this phenomenon is called kernlose winter. The annual amplitude of air temperature is not high and in the interior its value reaches 30-35°C. The continental type includes the whole Antarctic except the narrow coastal belt. Coastal - characterised by air temperature around 0°C in the summer period. The warmest month is January. The lowest temperatures occur in January (-30° do -40°C). The growth of temperature in spring delays the heat uptake for the melting of sea ice. The annual amplitude of the air temperature is quite high and exceeds 20°C. Due to the influence of circulation factors on the Antarctic the annual course of the air temperature shows a large variability from year to year.
EN
The meteorological measurements were carried out on NW Spitsbergen on the Waldemar Glacier (surface 2.66 km2) in three points: ATA (133 m a.s.l., marginal zone), LW1 (130 m a.s.l., snout of glacier), LW2 (380 m a.s.l., firn part). The base station of Toruń Polar Expedition is situated on the north part of Kaffioyra (KH, 11 m a.s.l.), about 3 km away from glacier. The air temperature and relative air humidity were measured by termohigrographs in standard meteorological boxes, and precipitation by Hellmanns pluwiometer in the period 14.07-8.09.1999. The weather conditions on the Kaffiöyra region are determined by solar and circulation factors. In the summer season 1999 north and east advection of air masses dominated. The meteorological conditions on Waldemar Glacier are formed by the influence of two contrasting environments: the glacier and its moraine foreground. The mean air temperature in summer 1999 at the Kaffiöyra equaled 5.4°C and at the moraine of the Waldemar Glacier (ATA) 5.2°C. On the glacier the air temperature was much lower, and on the snout (LW1) was 4.5°C and decreases with the altitude (LW2 3.2°C) . The average gradient of air temperature between LW1 and LW2 stands was 0.53°C/100 m. Between the warmed up dark moraine ground (ATA) and the melted surface of the glacier a ?thermal jump? occurred (0.4°C on the distance 160 m). The highest maximum of air temperature at KH was 18.1°C, and on the Waldemar Glacier 16.4°C (LW1) and 16.5°C (LW2). The relative air humidity on Spitsbergen are formed under the influence of oceanic water and foehn phenomena. In summer season 1999 the mean relative air humidity was 84% at the Kaffioyra and increased with the altitude on the Waldemar Glacier (LW1 ? 86%, LW2 ?89%). In the period 21-07-31.08 at the Kaffioyra sums of the precipitation equaled 58.4 mm and on the glacier: 85.2 mm (133 m a.s.l.), 100,6 mm (233 m a.s.l.), 108.9 mm (380 m a.s.l.) and 131.8 mm (421 m a.s.l.). In summer season the meteorological conditions on the Waldemar Glacier show a large variability. It is a result of incoming air masses, warm from moraine foreground up the glacier and cool from the glacier plateau, from the interior of Spitsbergen.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.