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Observations of anthropogenic global warming

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Papers on climate in Denmark

Posted by Ari Jokimäki on December 6, 2009

In the spirit of COP15, which is about to start, I give you a list of papers dealing with the climate of Denmark (mostly excluding Greenland) in various ways.

Daily ocean monitoring since the 1860s shows record warming of northern European seas – Mackenzie & Schiedek (2007) “We use four of the world’s longest calibrated daily time series to show that trends in surface temperatures in the North and Baltic Seas now exceed those at any time since instrumented measurements began in 1861 and 1880. Temperatures in summer since 1985 have increased at nearly triple the global warming rate, which is expected to occur during the 21st century and summer temperatures have risen two to five times faster than those in other seasons. These warm temperatures and rates of change are due partly to an increase in the frequency of extremely warm years. The recent warming event is exceeding the ability of local species to adapt and is consequently leading to major changes in the structure, function and services of these ecosystems.” [Full text]

Environmental response to the cold climate event 8200 years ago as recorded at Højby Sø, Denmark – Rasmussen et al. (2007) “The need for accurate predictions of future environmental change under conditions of global warming has led to a great interest in the most pronounced climate change known from the Holocene: an abrupt cooling event around 8200 years before present (present = A.D. 1950), also known as the ‘8.2 ka cooling event’ (ka = kilo-annum = 1000 years). … In an ongoing project, the influence of the 8.2 ka cooling event on a Danish terrestrial and lake ecosystem is being investigated using a variety of biological and geochemical proxy data from a sediment core extracted from Højby Sø, north-west Sjælland (Fig. 2). Here we present data on changes in lake hydrology and terrestrial vegetation in response to climate change, inferred from macrofossil data and pollen analysis, respectively.” [Full text]

The influence of climate change on stream flow in Danish rivers – Thodsen (2006) A paper that has to wait a bit for confirmation. “The influence of climate change on river discharges in five major Danish rivers divided into 29 sub-catchments is investigated for the future period of 2071–2100. … Mean annual precipitation is found to increase 7%, potential evapotranspiration to increase 3% and river discharges to increase 12% on average, between a control period (1961–1990) and the future period.”

The Climate of Denmark 2002 – Cappelen & Jørgensen (2003) Technical report. “Despite a cold ending 2002 was considerable warm with a annual mean temperature of 9,2°C. At the same time the year was wet and very sunny. The combination of extraordinary heat and at the same time a lot of sunshine and precipitation are remarkable. Globally the year was the second warmest on record.” [Full text]

The effects of climate change on the birch pollen season in Denmark – Rasmussen (2002) “During the last two decades the climate in Denmark has become warmer and in climate scenarios (IPCC, 2001) it is foreseen that the temperature will increase in the coming decades. … In this study the already observed effects on the birch pollen season are studied. … In Copenhagen there is a marked shift to an earlier season – it starts about 14 days earlier in year 2000 than in 1977, the peak-date is 17 days earlier and the season-end is 9 days earlier.” [Full text]

Lake-level changes in the Late Weichselian Lake Toevelde, Moen, Denmark: induced by changes in climate and base level – Noe-Nygaard & Heiberg (2001) “The lacustrine Toevelde basin is a key locality for the study of Late Weichselian sedimentological, geochemical and climatic development in Denmark. … The sediment record covers a time span from about 14,700 to 9000 cal yr BP and starts with resedimented till. … Sedimentological, geochemical and palaeoecological data show that Lake Toevelde underwent significant fluctuations. Some of which can be directly linked to climate changes. Some rises correlate, however, with damming of the Baltic Basin caused by isostatic uplift of barriers. High-resolution stratigraphy may thus allow distinction between lake-level changes caused by climate fluctuations and base-level changes which are ultimately related to isostasy.”

Large-scale aeolian sand movement on the west coast of Jutland, Denmark in late Subboreal to early Subatlantic time – a record of climate change or cultural impact? – Clemmensen et al. (2001) “Holocene dunefield construction on the west coast of Jutland was episodic. One of the most intense phases of inland sand movement and dunefield construction took place in late Subboreal to early Subatlantic time. … The onset of this phase of dunefield construction may be related to an abrupt climatic change in the North Atlantic region at about 800 BC and a likely increase in storminess.”

Eemian Lake development, hydrology and climate: a multi-stratigraphic study of the Hollerup site in Denmark – Björck et al. (2000) “A classic northwest European open section with lacustrine Eemian sediments, Hollerup, has been studied with respect to sedimentology, geochemistry, stable isotopes, diatoms and mineral magnetic analyses, and correlated by geochemistry and diatoms to a previously pollen analysed section by Andersen (1965). … Our studies show that the onset of the Eemian was characterized by a major lake level rise followed by an almost 3000 yr long period of high, but oscillating lake levels. It is argued that the latter part of this period of highly maritime climate can be defined as the Eemian climatic optimum. This period was interrupted by a few hundred years long phase of low lake level, coinciding with the immigration of spruce, followed by medium-high lake levels. The next c. 3500 yr, coinciding with the Carpinus pollen zone, seem to have been characterized by fairly humid and mild conditions, although slightly more arid than during the preceding optimum. The Carpinus period ended with a more than 1000 yr long gradual lake level fall, and this period of lake level change, concurring with the transition into the Pinus pollen dominated period, terminated with an extreme low lake level event. This 300–500 yr long arid phase coincides with a distinct peak in pine pollen, and was followed by higher but slightly oscillating lake levels in a cooler climate. The end of the Eemian seems to have been characterised by a gradual cooling, until almost pure clastic sedimentation and a marked expansion of herb pollen grains mark the onset of the Weichselian.”

Observed Air Temperature, Humidity, Pressure, Cloud Cover and Weather in Denmark – with Climatological Standard Normals, 1961-90 – Laursen et al. (1999) Technical report. “This report presents the observed air temperature, relative and absolute humidity, mean sea level atmospheric pressure, cloud cover, snow cover, snowfall, fog and thunder in Denmark on a monthly basis from up to 44 Danish stations. The observations mainly cover the climatological standard normal period 1961-1990, but some series covering periods of less than 30 years between 1961 and 1998 are also included.” [Full text]

Interglacial and glacial climate oscillations in a marine shelf sequence from Northern Denmark — a multidisciplinary study – Kristensen et al. (1998) “A 22.5 m long marine shelf sequence in northern Denmark covers the climatic shifts from glacial environments, through interglacial and into early glacial conditions. The interglacial was interrupted by two cool intervals. Also the early glacial succession experienced oscillations of the climate, and a period with ameliorated temperature conditions has been separated as an interstadial. … The climatic changes in this eastern part of the North Sea region are closely linked with changes in the North Atlantic circulation pattern, and the environmental fluctuations at Nørre Lyngby are therefore believed to reflect fluctuations in the past regional climatic and oceanic system.”

Morphology and vegetation of a dune system in SE Denmark in relation to climate change and sea level rise – Vestergaard et al. (1991) “Recordings by the Danish Meteorological Institute show, that the mean temperature of Denmark has remained fairly constant and the mean precipitation in winter has increased very slightly during the last c. 100 years, and that the relative sea level rise in Danish waters amounted to between + 9 cm and -3 cm during the same period of time. For the W Baltic area a doubling of CO2-level in the atmosphere is predicted to cause an increase in mean temperature by 3–4°C, an increase in length of growing season by c. 55 days, an increase in aridity, and a sea level rise of between 25 and 165 cm. Based on recent observations of morphology, soil and vegetation of a W Baltic dune system, possible effects of these changes upon vegetational composition, phytogeography, nutrient economy, stability, and ground water level of coastal dunes are discussed.”

Closely related

Climate Research in Denmark

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Wrong trend

Posted by Ari Jokimäki on November 2, 2009

Hey, this is wrong way around!


In this particular occasion (today’s situation just few minutes ago), there is 32 paperlist views and 9 clicks to papers. This is quite common situation. The paperlists in this blogs are just lists of links to scientific papers. I’m not even giving full abstracts in the lists, just a few selected sentences.

So click those links, dear readers. 🙂

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New index page

Posted by Ari Jokimäki on September 7, 2009

I have made an index page for the paperlists, as requested:

If you have any comments and suggestions about that, post them here.

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Paperlists – some updates

Posted by Ari Jokimäki on September 5, 2009

I have been wondering if the links in my paperlists have been unclear, especially if everyone have realized that there usually are two links; first one to the official abstract page of the paper, and the second one to the PDF file containing the whole paper. Links have been side-by-side so they might be unclear. Therefore I have decided to move the PDF links at the end of each entry so that they are clearly separated from the abstact links. I’ll update all the old postings little by little.

Some of you may have wondered what are the paperlists for that I keep posting. One reason for it is that I’m using the paperlists myself, so they serve as linklists for my own benefit. I also hope that others benefit from them too in order to gain some real information about climate science straight from the source of the information, i.e. the scientists.

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AGW Observer

Posted by Ari Jokimäki on July 28, 2009

Hi and welcome to AGW Observer!

This blog is about climate science with an emphasis on the observations of the climate change that is currently ongoing. Specifically the emphasis will be on those observations that show that it is mankind that is and has been causing this current climate change by greenhouse gas emissions. The AGW in the title stands for Anthropogenic Global Warming, which is a commonly used term for the current human-caused climate change.

I am not a professional climate scientist, but just an interested layman who has been getting familiar particularly to the observational side of the issue by reading the research papers on the subject. I hope I can offer some relevant information on the subject especially as the public discussion on the subject tends to focus more on what climate models can do instead of emphasizing the observational body of evidence which is very large and in my opinion convincing by itself even without far-reaching climate theories or models.

Have fun.

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