Skip to content

Deciphering Svalbard’s climate history

April 11, 2019
tags: ,

By Paul Homewood



We are familiar with ice core data from Greenland showing that the climate there was warmer in the recent past. This study of ice cores in Svalbard, published in 2011 comes up with similar results:


During the past thousand years, the average winter temperature in Svalbard’s “capital” Longyearbyen has varied from minus 5 degrees Celsius around 1000 AD to minus 25 degrees around 1850.

“Stories about how cold it was in Svalbard during the golden age of hunting and trapping in the 19th century are not exaggerated,” says senior research scientist Elisabeth Isaksson. Using ice cores from three of Svalbard’s glaciers, she and her colleagues have reconstructed a thousand years of variations in winter temperatures for Longyearbyen and for Vardø at the northeastern tip of mainland Norway.

Temperatures and isotopes

Winter temperatures have been measured since 1911 in Longyearbyen and since 1840 in Vardø. Researchers from the project Svalbard ice cores and climate variability (SVICECLIM) have combined these valuable time series with data from ice cores drilled at three different sites in Svalbard. The research has received funding under the Research Council of Norway’s programme Climate change and impacts in Norway (NORKLIMA).

The researchers have made a particularly detailed study of a 121-metre long ice core extracted from the Lomonosovfonna glacier, 1230 metres above sea level. The ice at the bottom of the core is about 1000 years old.

The proportions of the stable isotopes 18O and 2H in ice vary with temperature. Isotopic composition can therefore be used as a proxy for historical air temperatures before the period for which we have instrumental measurements. Thermometer measurements from Vardø and Longyearbyen overlap with the ice core data back to 1911 and 1840. The researchers used the measured temperatures from these two sites and the isotope data from the ice core from the overlapping time period (a method called “scaling”) to quantitatively reconstruct earlier temperature variations.


Ice cores from Svalbard provide a record of climate history (Photo: SVICECLIM)


Long period of cooling

“Data from a single ice core may not be representative. But we have used ice cores from several different parts of Svalbard, and can be fairly confident about our findings on climate fluctuations in Svalbard and North Norway as far back as the Viking Age,” says Elisabeth Isaksson.

The period between the 1300s and the end of the 1800s is known as the Little Ice Age. The SVICECLIM researchers have found no evidence of abrupt temperature changes during this period.


Three periods

The SVICECLIM project has shown that trends in winter temperature in Svalbard and North Norway over the past thousand years can be roughly divided into three. To start with, there was the long period of steady cooling beginning in the Middle Ages. This was followed by the very cold period of the 1800s, and then by rapid warming that started in about 1900.

“The rapid warming during the 20th century was already well documented. Now we have more reliable information on both the 1800s and earlier centuries. The ice core data suggest that Svalbard’s climate was about as mild in the 1300s as it is today. In fact, the summer temperatures may even have been higher,” explains Elisabeth Isaksson.


Elisabeth Isaksson has headed a project to reconstruct historical temperature fluctuations in Svalbard and North Norway. (Photo: SVICECLIM)


Elisabeth Isaksson and her colleagues are by no means the first scientists to have drilled ice cores to investigate past climate change, but nobody has previously made such detailed studies of Svalbard ice cores. The best-known large-scale ice coring programmes have been carried out in Greenland and Antarctica. Some of the ice cores cover a much longer time span than those from Svalbard – the deepest ice core from Antarctica goes back 800 000 years.

Svalbard has a maritime climate, which is strongly influenced by temperature fluctuations in the Atlantic Ocean. Greenland and Antarctica are much more like large continents with their own climate. This means that the ice core data from Svalbard complement data from Greenland and Antarctica.
Ice cores can tell us about more than temperatures

Elisabeth Isaksson and her team have also extracted other information from the ice cores. They have found evidence of the eruptions of the Icelandic volcanoes Laki and Grimsvötn in 1783 and 1906, Soviet nuclear tests in the 1950s and 1960s and the Chernobyl disaster in 1986. All these time markers are important for the researchers when they try to date the different layers of the ice cores.

The researchers have also been able to study the spread of pollutants to the Arctic. We know that the spread of sulphur in the atmosphere started around 1850. Concentrations of pollutants such as PCBs, DDT and brominated flame retardants rose gradually during the 1900s, but have begun to decrease again as their use has been banned. Now new pollutants are appearing in the upper layers of ice on the glaciers.

  1. April 11, 2019 9:24 pm

    Alarmists have been exploiting the recent water leaks at the Svalbard Global Seed Vault, and many greenies visit the place to hold hands and sing Kumbaya, which is funny because of the essential use of fossil fuels to get there, to stay warm and fed when there (the island has a coal-fired power station), probably feasting on reindeer steaks.

    But, the notion that oil saved the local whales from hunting is a vicious denier slur … the local whales had been hunted to near extinction before the oil industry got going. Kumbaya, oh for the good old days before coal and oil.

    • April 12, 2019 8:48 am

      Forgot to mention that the water leaks are not just any old water, they come from the sacred permafrost, making Svalbard an essential visit for greenies on a climate pilgrimage.

  2. April 11, 2019 10:18 pm

    Reblogged this on Climate Collections.

  3. A Norwich Tory permalink
    April 12, 2019 10:17 am

    I look forward to hearing Roger Harrabin on this on the BBC news.

  4. April 12, 2019 10:17 am

    From the blog post:
    ice core data suggest that Svalbard’s climate was about as mild in the 1300s as it is today. In fact, the summer temperatures may even have been higher

    That would be the closing stage of the Medieval Warm Period. Similar story in Greenland:

    Interpretation of ice core and clam shell data suggests that between 800 and 1300, the regions around the fjords of southern Greenland experienced a relatively mild climate several degrees Celsius higher than usual in the North Atlantic

    ‘several degrees Celsius higher’ – and warmists think a fraction of that nowadays must be man-made?

    Another point:
    Due to the Gulf Stream, Svalbard’s west coast is the world’s most northerly ice-free area.

  5. TinyCO2 permalink
    April 12, 2019 10:32 am

    Svarlbard is a very useful metric for the Atlantic. Important because the ‘missing’ modern heat is supposed to be in the oceans. It suggests that the Atlantic wasn’t any colder in the 1300s than it is now. If anything about CO2 theory is correct, you would expect modern winters to be warmer, especially at high latitudes. It’s interesting that summer temperatures might have been higher. Are we seeing a continuation of the downward trend in warm spikes shown in the Greenland cores but with a small boost from CO2? Or should we be still on the overall downward trend as illustrated by the LIA and CO2 is the only thing stopping us from falling into a real ice age?

    I’d like to see modellers recreate the last 10,000+ year temperature trends using the inputs they think matter because basic solar doesn’t seem to explain the past. If we don’t know what cause the RWP, MWP, the Holicene Optimum and the LIA, how can we predict what we will experience naturally? Are we due a double warm period like 400,000YBP or are we near the end? Do we count the period prior to the Younger Dryas as the start of this warm period? My wild ass guess is that the sun does more stuff than we’ve been able to observe and insolation is only part of what triggers an ice age or a warm period.

    • matthew dalby permalink
      April 14, 2019 12:42 am

      You seem to be unaware of the solar cloud theory. Basically galactic cosmic rays create ionized particles in the atmosphere that in turn act as nuclei that water vapour can condense on to form clouds. When the sun is active (e.g. during the 20th century, during the Medieval Warm Period, roughly 10th & 11th centuries, and the Roman Warm Period) its magnetic field is stronger which results in fewer cosmic rays reaching the Earth, meaning fewer clouds, and more sunlight reaching the surface causing warming. The opposite happens during periods of lower solar activity such as happened during the Little Ice Age (known as the Maunder and Dalton minimums). Although ocean cycles such as the PDO and AMDO can cause warming and cooling on time scales of several decades, and CO2 emissions may have caused a small amount of warming, the solar cloud theory is the only thing I have read about that can explain temperature changes on a millenial time scale. The only answer that alarmists have is to try and downplay the change in temperature between the MWP and LIA (a la the hockey stick and its countless imitators) or talk about solar irradiance and either willfully or mistakenly take this to be the only way in which the sun can influence climate. Basically the modellers have invested so much time and their reputations in the CO2 theory, plus it has become so politicised that they aren’t going to admit they got it wrong, which is why they talk about temperature changes since the industrial revolution as the CO2 theory can’t explain earlier temperature changes.
      I recommend anyone who is skeptical about the “consensus” view of climate change to read “The Chilling Stars” by Henrik Svensmark & Nigel Calder (ISBN-13: 978-1840468-15-1). In my opinion the best book yet written about climate change.

  6. dave permalink
    April 12, 2019 12:00 pm


    This following – “Believing six impossible things…” – is of interest, although it requires a little knowledge of the hidden compromises in computerized mathematics to appreciate some of it.

  7. April 12, 2019 1:14 pm

    @Dave does that auto embed here ?

    • April 12, 2019 1:14 pm

      yes all I did was post the Youtube URL , and it auto-embedded

    • April 12, 2019 1:36 pm

      Is this the video where he explains why comparing Arctic ice extent year to year is crazy

      • Athelstan. permalink
        April 12, 2019 3:18 pm

        I wish sometimes that I could uptick you, keep up the good work stew!

        a blumin’ stalwart and very important contributor.

      • April 12, 2019 10:08 pm

        I just clicked the LIKE button next to your post
        ,cos viewing this blog via gives you that facility

      • dave permalink
        April 12, 2019 4:41 pm

        “Is this the video…?”

        No; it is more about the ignoring of fundamental mathematical and philosophical constraints. And, by implication, how “Computer says!” in the mouth of “a scientist” is akin to a low rank priest pretending to be transmitting directly a message from God.

  8. Athelstan. permalink
    April 12, 2019 3:15 pm

    “The ice core data suggest that Svalbard’s climate was about as mild in the 1300s as it is today. In fact, the summer temperatures may even have been higher,” explains Elisabeth Isaksson.”

    I’ll be gone to hockey sticks and thoroughly trashed.

Comments are closed.

%d bloggers like this: