About the Cache:

This cache guides you to Lake Biograd and is established to raise public awareness on ongoing climate change by showing you a beautiful glacier lake in an amazing environment (and teaching you a lesson ;)).

Please be aware that this earthcache is placed in a national park and therefore, an entry fee of 3 € per person is required to maintain environmental protection. Parking slots are available directly at the lake.

How to get to the coordinates?

The easiest way is taking the marked educational trail. The complete trail is running once around the lake (approximately 3.5 km) and takes 1 hour. It is also possible to rent boats at the lake and approach it by water-side.

Safety first:

Do not exceed any security border. No photo is worth to risk your life!

Lake Biograd is a freshwater lake of glacial origin located in the heart of Biogradska Gora national park. It is the largest and most famous lake of Bjelasica. The lake has been created in the thermal basin of Biograd river. Biograd river is supplying the lake with water and Jezerštica river is draining it.

Lake Biograd Lesson

Lake Biograd is a glacial lake. It is included in the Biogradska Gora National Park. The lake is located on the Bjelasica mountain in northern Montenegro.

Glacial lakes are refered to as water bodies originated by glacial activity. They get formed when a glacier erodes the land and afterwards melts, filling the depression created by the glacier. Roughly 10,000 years ago, close to the end of the last glacial period, European glaciers began to retreat. Particularly between hills many glaciers left behind large deposits of ice and stones. By the end of the ice age those ice deposits melted and created glacial lakes.

Often you can find further evidences of the glacier surrounding the lakes, such as moraines and eskers. The coastlines of such an area are commonly irregular, reflecting same geological processes. By contrast, lakes attached to rivers appear smoother. These areas were carved more by water erosion than coastlines without. However, in general the water exchange of glacial lakes is relatively slow. Since the glaciation of the Little Ice Age, 50% of all glaciers over the world got lost due to climate change creating a shift from frozen to liquid water. Besides that glacial lakes are an important component of Earth's hydrosphere, they can further record regional climate change in different time scales. Thus, they are often considered as one important information carrier to reveal climate change and its regional responses.

The formation and characteristics of glacial lakes vary between location. Internationally, there has been no accepted standard for a classification system of glacial lakes. One commonly known classification system divides the lakes into:

1. Glacial erosion lake - water body in the depression formed by erosion and abrasion of glacier in the process of glacier movement

2. Moraine-dammed lake - water body between moraine ridge and glacier due to the obstruction of moraine ridge

3. Ice-blocked lake - dams are composed of glacier ice

4. Supraglacial lake - water body on the surface of glacier due to different ablation

5. Subglacial lake - water body within the glacier

6. Other glacial lake - water body formed by landslide, rock collapse, avalanche and debris flow blocking the valley

Tasks

Tasks to log this cache as found

Go to the given coordinates and answer the questions.

Station 1:

Here you can find a table with the most important key facts about the lake. Please message me lake area, volume, length, maximum width, maximum depth and coastline length. Considering the knowledge you have gained up to now and taking books or internet for help, please tell me which kind of glacial lake we have here and explain why (Hint: What do you see at the location and why?).

Station 2:

Here you can find a special stone. Please measure the diameter of the stone and describe color and shape. Please give a suggestion which kind of mineral it might be. How did it end up here?

Station 3 (anywhere at the lake):

Provide a photo of you or your GPS in front of the lake in order to monitor further development of the lake.