www.geostrategis.com/p_mapm2.html

www.ecoinformatics.info

Google Earth and Climate Change: Google Earth provides a fascinating way to explore the earth remote ecosystems.
Few people would imagine that GE has the resolution and detail to monitor ecosystems, but an experienced interpreter can do remarkable
things with Google Earth.
A 2005 Google Earth visit to one of my old research sites in Manitoba, Canada, showed that Google Earth can be used to approximate the melting rates of permafrost in peat landforms. These two combined inages show a comparison of permafrost in peatplateaus just north of Lake Winnipeg. This area is within the so called southern sporadic permafrost zone, but because of its unique wetland situation permafrost is quite widespread (see for example E in 1926) and visible. Even the low resolution Google Earth images shows the melting edge clearly. The two major peat islands are aslo shown on the second image below as B and C.



The compsite figure below shows a combination of a1926 oblique aerial photo, a 1947 vertical air photo projected as oblique and a 2005 oblique Google Earth image. The permafrost around A is still present in 1947 but totally melted in 2004. The peat plateau B shows some melting (collapse holes) inside the plateau in 1947; but in 2005 they joined together and are forming a peripheral collapse. Area C is interesting because it was burned before 1926 regenerated a black spruce cover and shows still its frozen state in 2005. In fact the melting process in B and C seems very comparable. So fire does not necessarily increase the rate of permafrost melting. On the other hand, the the small peatplateau at touching the top of (A) melted within years after a fire in the late 60's.






A close up view from helicopter: Black Spruce (Picea mariana) grow on the frozen core in the middle. They are about 12-15 meters in height. The collapsing edge shows surface water and leaning trees and trunks sinking in the non-frozen wetlands. Tamarack (Larix Laricina) growth is denser around the original edge of the palsa.


Extensive collapse scars of former peat plateaus. Very little permafrost is left except for areas near (2). This area was burned a number of years ago. In these small areas of permafrost white birch and black spruce regeneration is seen. The relative recent collapse areas are marked with (1), older scar areas with (3)



Analysis page comparing 1929 and 1947 aerial photographs, and 2005 Google image and field work photos available at http://www.geostrategis.com/p_mapm2.html

website: www@geostrategis.com

This Peatland Sensitivity Map to Climate Warming was prepared by Kettles and Tarnocai (1999) and superimposed on Google Earth Satellite image. It covers the exaple of permafrost melting in the previous post. It shows that this area is considered extremely sensitive to climate warming.


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It is displayed as overlay in Google Earth for Manioba and a portion on Ontario in Canada.

In this area the southern permafrost line would move about 300 kms North.

Permafrost Sensitivity Map


In Canada peatlands cover about 12% of the land surface. (over 1.13 million km2). A large part of the carbon stored in peatlands could be released in the atmosphere as carbon dioxide and methane, further increasing climate warming.
More Information at: http://www.geostrategis.com/p_sensitivity.htm

http://www.geostrategis.com/p_mapm2.html

Hi jeanthie and welcome to Google Earth!

These are great - thank you for posting them!

Dear Heamit,
Thanks for your supportive comments. It is kind of nice to get back to use Google Earth to get back to my deep past. I used to be the first Head of Applications Development Division of the Canada Centre for Remote Sensing (1973-1975). Interpretation and analysis (visual or automated) of satellite and airborne images have always fascinated me, and GE allows me to play with this again. Of course I have done this stuff with ERTS and LANDSat imagery in those days, but now it is accessible to almost everyone!

By the way, the interesting part of this permafrost is that it is at the most southern edge of its occurrance. This is by no means the Arctic, but the Mid Boreal zone. While melting rates have been reasonably consistent in the last 50 years, you could expect significant more change in the next 20 years. Also surprising is that the permafrost occurs in some areas within 50 meters of the shoreline. See image below



for more information

www.geostrategis.com/p_mapm2.html

www.ecoinformatics.info

Quote:

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Few people would imagine that GE has the resolution and detail to monitor ecosystems, but an experienced interpreter can do remarkable
things with Google Earth.

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I think you will find that GE is used more and more for scientific research and documentation as more scientists find just how useful it is. The link to the website is very useful also. Thanks for your post.

Impact of Forest Fires on Melting of Permafrost in Peatlands.
The GE image below shows This is an example of a 1930 fire which burned part of a large peatplateau complex. After the burn black spruce regenerated naturally and no increased melting was observed in 1974. Even in 2004 this Google Earth image shows that permafrost still exists with a similar distribution as in the non burned area. Melting has continued at a steady pace.. Fire records in this area do not show significant fires in the last 15 years. A few very small areas can be found (see recent small burn), bit the immediate impact of those cannot be assessed. GE resolution is not adequate for that in this area. Although fire generally did not have an impact of acceleration of melting rates, one particular small peatplateau totally collapsed after a burn in 1965.



This picture below was taken 1970 from helicopter. It shows the area burned in previous image. The area B was not burned in 1930, the area A is also a part of a stand which survived the fire. The regeneration is primarily Black Spruce, with an occasional bright dots of White Birch. The light colored collapse areas around the edge and in the centre are quite distinct.


Typical fire regeneration on permafrost peatplateaus in this area, trees are 30-40 years old. The peat auger in this picture is in the permafrost which starts at about 50 cm or 2 ft below the surface. (late August).




Website: www@geostrategis.com

More information

http://www.geostrategis.com/p_mapm2.html

Palsa near Cranberry Portage, Manitoba.



This image gives a good cross section of the permafrost development in the peat and clay layer. The fieldwork for this diagram was carried out between 1968-1970 by two of my forest ecologist friends Steve Zoltai and Charles Tarnocai.

This cross section is very indicative of the situation described in the first post on permafrost melting just north of Lake Winnipeg. The glacial lake Agassiz clays form the mineral layer, which is covered by up to two meters of organic material. Permafrost extends into the clay layer. Onviously the premafrost was developed after the galcial lake retreated and the organic layer formed. It is actually the result of a very intricate interaction of climate, microclimate and forest cover and insulating properties of sphagnum mosses.

More information at

http://www.geostrategis.com/p_mapm2.html
and
www.ecoinformatics.com

Jeanthie,

Thanks for the great post. You have done some wonderful work.

Rick Marshall

This folder contains a series of aerial photos taken between 1926
( aerial obliques) , 1946, 1967, 1971 which provide a source of comparison for studying the melting of permafrost in the form of palsas and peatplateaus at the most southern limits of occurance.
For more information: www.geostrategis.com and
http://www.geostrategis.com/p_mapm2.html




Site A:
Collapsing of permafrost is regularly distribute over the area. The red areas show the location of permfrost melting between 1947 and and 1957. Most of the area was burned in 1930 (except the darker treed- black spruce islands (on permfrost), but there are no signs that the burn accelerated melting rates. For example some of these darker 'black spuce on permafrost islands' have almost completely melted away between 1967 and 2000+, the date of the GE image. use the transparency slider to compare the two dates. Maximum extent of the permafrost in this area is likely correlated with the 'little ice age'. Just outside the overlay about 1.3 km north west of the left top corner is a small area burned about 3 years before the date of the GE image.



Site B: This area is interesting because most of the permafrost has diappeared. The small dark tread areas of black spruce on permanently frozen peat plateaus were all that was left of the once extensive permafrost. At its maximum extent about 65% of this site had permfrost. In this area most of the melting actually occured before 1946. In 1967 only the small dark spots remained. They tend to occur on the edges of the former peat plateaus. Most of these have disappeared now or are significantly smaller. Barely 1% of this site still has permafrost.Aerial Photo 1967; Red marks show areas melted between 1946 and 1967. Fieldwork carried out in 1973.



Site C:This photograph was taken as part of a multi-sensor aerial flight over the study area by the Canada Centre for Remote Sensing Airborne Division for the Manitob Remote Sensing Program. The colour photo was taken towards the end of the growing season. This site is remarkable because many of the small permafrost island still exist today and show relative small rates of melting.


Site D: Significant melting occured here before 1926 and this 1926 oblique photo gives an excellent image of the collapse scars which remain after the melting of the permafrost. Melting has continued since 1926, but permafrost remains are still visible on the GE image
Approximatearea coverd by the oblique aerial photo.


Site E:
This photo compared with the underlying Google Earth image provides a 60 year time frame to study the melting of permafrost. The permafrost in the form of Black Spruce forested peat plateaus and palsas is delineated on the photo after filedwork in this area in 1969-1971. Most of the smaller bodies of permafrost have disappeared and the larger ones show slow but steady melting around the perimeter.