Dynamic climatologic processes of barometric cave systems using the example of Jewel Cave and Wind Cave in South Dakota, USA

Abstract

Ringeis: Dynamic climatologic processes of barometric cave systems using the example of Jewel Cave and Wind Cave in South Dakota, USA Jewel and Wind Cave are two big barometric cave systems in Sout� Dakota, USA. The entrances of Jewel and Wind Cave are roug�ly 50 km apart, and until now it is unknown w�et�er t�eir entrances belong to two separate caves or to one muc� larger cave system. One possibility for testing t�ese two competing �ypot�eses is to measure and analyse t�e climatic conditions in t�e vicinity of t�ese entrances and wit�in t�e caves in detail. In t�is context, t�e t�ermal conditions and air currents are crucial. These in turn can be c�aracterised by t�e spatial and temporal patterns of t�e dynamics of air entering and leaving t�roug� t�e respective entrances; even t�oug� t�ese dynamics are coupled to atmosp�eric pressure fluctuations outside t�e caves, t�ey differ for different cave systems and provide a "fingerprint" t�at �as implications for t�e size and structure of individual cave systems. To give an example, Jewel and Wind Cave as t�e second and fourt�-largest cave systems on eart� s�ow some similarities, but many more noticeable differences regarding t�eir climatological be�aviour, despite t�eir close proximity to eac� ot�er. The last big measurement campaigns on t�e climatic systems of t�e two barometric caves were carried out by Herb and Jan Conn in t�e 1960s, (Conn 1966). Despite t�eir elementary work, t�e tec�nical possibilities were very limited in t�ose days. The self-constructed me-c�anical measurement equipment could only be used for basic measurements. Herb Conn was still able to identify t�e basic mec�anism very clearly. He also carried out a number of different calculations on barometric air flow t�at remain important COBISS: 1.01

A review of factors affecting cave climates for hibernating bats in temperate North America

“…Inversions are temperature increases at higher altitudes instead of decreases as is typical. Thus, entrances in valleys may draw in colder air masses than entrances on hill tops during winter (Pflitsch et al 2010). Forest cover may also reduce MAST Fig.…”

“…Changes in barometric pressure can affect airflow (and temperature) into caves but is likely not as widespread a factor as thermal convection in most caves (Tuttle and Stevenson 1978). Because thermal and barometric processes are happening concurrently in many caves, the exact processes driving air movements can be difficult to discern (Pflitsch et al 2010). In most caves (especially small caves or caves with large openings), airflows due to barometric changes are hardly measureable because of the small amounts of air being exchanged and the almost immediate equalization between outside and inside pressure (Pflitsch et al 2010).…”

The importance of air temperature as a key parameter to identify climatic processes inside Carlsbad Cavern, New Mexico, USA

“…In the reverse case, with low atmospheric pressure drawing air out of the cave, warmer air flows from the Lake of the Clouds or the Bell Cord Room into the Left Hand Tunnel, resulting in rising air temperatures. This, in comparison to the effects in the wellknown barometric caves like Wind Cave and Jewel Cave in South Dakota (Pflitsch et al, 2010), seems to be relatively insignificant, but it explains a few climatic effects inside the Left Hand Tunnel and also for the whole cave.…”

Climatologic studies inside Sandy Glacier at Mount Hood Volcano in Oregon, USA

“…These flow rates, however, are still higher than those of many other known static and even dynamic caves. (Pflitsch et al, 2010) The flow direction reveals a clearly pronounced vertically structured flow system in this part of the glacier cave. Thus for the area close to the ground, a clear and steady outflow was found, while air was flowing in upwards along the ceiling.…”

“…27 and 28). Some of us who have been inside a cave know strong winds caused by convection or barometric pressure effects very well (Pflitsch et al, 2010). But a combination of high airflow velocities and high temperatures inside a glacier cave as a mostly frozen environment had not been observed or measured yet.…”