Summer Institute for Historical Geophysics, Åland Islands

On the character of the institute

The Summer Institute for Historical Geophysics, on the self-governing Åland Islands in the Baltic Sea, started in 1993. For more than 30 years it has performed scientific research and issued publications and books within its field; all of them are available here.

The publications and books of the institute deal with historical geophysical data and their use in geophysics as well as history. Emphasis is on the Nordic countries and the Baltic Sea area. Geophysically, they are concerned with positioning, gravity, postglacial rebound, tides, sea level changes, and climate changes. Historically, they are concerned with the times from the Vikings up till today, with a concentration on the last three centuries.

Publication series: Small Publications in Historical Geophysics

The series “Small Publications in Historical Geophysics” contains 32 publications, which are accessible below; they have also been issued in print.

1. Ekman, M: Postglacial uplift of the Åland Islands, and the world's oldest preserved sea level gauge. 1995.
2. Ekman, M: Extreme annual means in the Baltic Sea level during 200 years. 1996.
3. Ekman, M: Anomalous winter climate coupled to extreme annual means in the Baltic Sea level during the last 200 years. 1997.
4. Ekman, M, & Mäkinen, J: An analysis of the first gravimetric investigations of the Earth's flattening and interior using Clairaut's theorem. 1998.
5. Ekman, M: Long-term changes of interannual sea level variability in the Baltic Sea and related changes of winter climate. 1998.
6. Scherneck, H-G, & Ekman, M: Analysis of tidal observations in the Arctic Ocean made during the Vega expedition. 1999.
7. Ekman, M: Determination of global sea level rise and its change with time. 2000.
8. Ekman, M: Computation of historical shore levels in Fennoscandia due to postglacial rebound. 2001.
9. Ekman, M: An investigation of the tidal conditions at the loss of the world's most impressive sailing ship. 2002.
10. Ekman, M: The visibility of the midwinter sun at the first Viking settlement in America - calculations compared with the Icelandic sagas. 2002.
11. Bergström, H, & Ekman, M: A period of anomalous winter climate and the Scandinavian glacier maximum in the 1700s. 2002.
12. Ekman, M: The world's longest sea level series and a winter oscillation index for northern Europe 1774 - 2000. 2003.
13. Ekman, M: A royal Swedish-Norwegian Viking fleet conflict studied by postglacial rebound and other calculations. 2004.
14. Ekman, M: Changes in winter climate variability deduced from the Baltic Sea level, and the winter that never arrived. 2005.
15. Ekman, M: The first land uplift map that could have been constructed - but never was. 2006.
16. Ekman, M: A secular change in storm activity over the Baltic Sea detected through analysis of sea level data. 2007.
17. Ekman, M: CPS - A forerunner to GPS invented by an Åland traveller in the 1700s. 2008.
18. Ekman, M, & Ågren, J: A study of Tycho Brahe's astronomical latitude determination of Uranienborg using satellite positioning and deflections of the vertical. 2009.
19. Olsson, P-A, & Ekman, M: Crustal loading and gravity change during the greatest storm flood in the Baltic Sea. 2009.
20. Ekman, M: An investigation of a pioneering triangulation across the Åland Islands. 2009.
21. Ekman, M, & Ågren, J: Reanalysing astronomical coordinates of old fundamental observatories using satellite positioning and deflections of the vertical. 2010.
22. Ekman, M: A geophysical and astronomical analysis of an old painting of the Stockholm sluice. 2011.
23. Ekman, M, & Ågren, J: A study of Celsius’ astronomical latitude determination of the Uppsala observatory using satellite positioning and deflections of the vertical. 2012.
24. Ekman, M: Postglacial rebound modelling during 300 years based on Fennoscandian sea level data. 2012.
25. Ekman, M: An investigation of Celsius’ pioneering determination of the Fennoscandian land uplift rate, and of his mean sea level mark. 2013.
26. Ekman, M, & Ågren, J: A partial reanalysis of the French arc measurement at the Arctic Circle to prove Newton’s theories. 2013.
27. Ekman, M: An investigation of the first determination of heights of Nordic lakes above sea level. 2014.
28. Ekman, M: On the first conformal projection in official topographic mapping. 2015.
29. Ekman, M: The midwinter sun at Viking settlements in North America and the North Atlantic Islands – Calculations compared with the Icelandic sagas. 2016.
30. Ekman, M, & Olsson, P-A: Gravity determinations at the observatories of Uppsala and Stockholm during three centuries. 2017.
31. Ekman, M: Calculation of historical shore levels back to 500 A.D. in the Baltic Sea area due to postglacial rebound. 2017.
32. Ekman, M: A study of sleep time as a function of season of the year in the 1700s using geophysical data. 2018.

Book: The Changing Level of the Baltic Sea during 300 Years: A Clue to Understanding the Earth

In this book sea level data from the Baltic Sea spanning nearly 300 years are used to draw conclusions about the Earth as a whole: its interior, its oceans, and its atmosphere. For information on how to buy the book see How to buy a book below. The book is also available here as a pdf file.

Specifications of the book:

• Description of the book and table of contents
• The whole book as a pdf file (37 MB)

Book: Where on Earth are We? Using the Sky for Mapping the Nordic Countries 1500 - 2000

In this book data from positionings towards celestial bodies during 500 years are used to draw conclusions about the mapping of the Nordic countries and its development up till today’s satellites. For information on how to buy the book see How to buy a book below. The book is also available here as a pdf file.

Specifications of the book:

• Description of the book and table of contents
• The whole book as a pdf file (6 MB)

Book: The Man behind "Degrees Celsius": A Pioneer in Investigating the Earth and its Changes

In this book the life and works of Anders Celsius in the early 1700s are investigated, including early studies on latitude, longitude, gravity, land uplift, sea level change, temperature, air pressure, magnetism and northern lights. For information on how to buy the book see How to buy a book below. The book is also available here as a pdf file. (For a booklet on Celsius in Swedish, see the Swedish version of the web site.)

Specifications of the book:

• Description of the book and table of contents
• The whole book as a pdf file (15 MB)

Book: Gravity in the Nordic Area from Newton till Today: What, how, and why?

This is a book not only for gravity people, but also for others who have wondered what gravity actually is, how gravity on the Earth and especially in the north has been determined through history, and why so much effort is put into obtaining knowledge of gravity. For information on how to buy the book see How to buy a book below. The book is also available here as a pdf file.

Specifications of the book:

• Description of the book and table of contents
• The whole book as a pdf file (37 MB)

How to buy a book

A book can be ordered as follows: 1) Send 20 euro or its equivalent to the International Red Cross. 2) Send an e-mail to martin.ekman[symbol]​historicalgeophysics.ax informing that the amount has been paid, which book is wanted, and the postal address where to send the book. 3) The book will normally be shipped within a week.

A little about the person behind

The person behind the institute is Martin Ekman, associate professor in geophysics at Uppsala University in Sweden. He has worked as a research geodesist in Sweden and as a lecturer in nautical geophysics on the Åland Islands, besides running the activities of the institute. His scientific papers, besides the ones above, have been published in various international journals, mainly Geophysical Journal International, Journal of Geophysical Research, Global and Planetary Change, Terra Nova, and Bulletin Géodésique.

Contact

For questions, if any, contact martin.ekman[symbol]ha.ax.