Fans of Steven Spielberg will remember the opening scene of Arachnophobia, which showed thousands of spiders crawling in a large cave. Speleologist Giovanni Badino can tell you all about that cave -- that it is one kilometre long, 150 meters wide, and has a 350 meter deep shaft -- because Badino has vivid memories of the cave Sima Aonda, in Tepui, Venezuela. "We were almost trapped inside the cave because of a [waterfall] of 300 meters falling around [us]," says Badino. It happened in 1994.
His team of 10 was dragged down to the bottom of the cave by a [waterfall] that formed due to heavy floods. "We spent the whole night returning to the surface [of the cave], leaving two people there." Twenty hours after the fall, the rest of the team was finally brought on dry land. "It was a situation of extreme difficulty, in another world," says Badino. But what struck him most was not the danger of the situation -- it was how beautiful and fascinating he still found the underground world to be.
The underground is not an environment that many scientists will feel comfortable working in. But for those with a taste for adventure -- and no claustrophobia -- a whole new world opens for exploration. Job opportunities in this field may still be very few, but with new technologies developing, Badino sees them expanding fast in the future. "We are only in the commencement of really studying the underground world," says Badino.
In addition to Venezuela, Badino's research interests have taken him to Chile, Brazil, Mexico, Argentina, Nepal, Uzbekistan, Pakistan, Iceland, and Antarctica. Most of these expeditions took place with Associazione La Venta  , a geographic exploration team that Badino helped found in 1990.
When he is not exploring caves around the world, Badino is developing theories of underground fluid and heat exchange at the Department of General Physics at the University of Turin, in Italy, and making use of an underground lab he has set up 80 km from the campus.
Originally a specialist in cosmic ray physics -- mainly underground supernova neutrino detection -- Badino is now studying underground climate and how it relates to outside climate. Climatic parameters in caves -- temperature, humidity, and water discharge -- are very stable over a period of time that is short on the geological scale, because they remain close to equilibrium with the outside atmosphere. Still, "the caves are never in exact equilibrium with the outside." Badino studies "the effects of small disequilibria between the external and internal climates." In a closed system like a cave, even minor fluctuations can have a major impact. A very small variation in temperature, for example, can cause water to condense on the cave walls and dig into the rocks, leaving a record of the current state of the atmosphere outside.
"The main problem [in my research] is technical," says Badino. The climatology instruments currently available are made to measure outside temperatures, which commonly fluctuate 15 degrees Celsius over a single day. Within a cave, you'll be hard-pushed to find temperature variations exceeding a tenth of a degree. "We have instruments for cave climate that give us very bad accuracy and are currently not sufficient to understand the physical processes that are working underground," says Badino. One way around this is to use 10 to 20 thermometers to give an average value and capture the fluctuations. Meanwhile, Badino is also looking into designing instruments that are sensitive enough for underground research. "It is a small field, but I am a pioneer for the theoretical modelling of these [physical processes] and for pushing the accuracy [of the instrumentation]," says Badino.
Working in an extreme environment often means having to plan as much as possible, then adjusting the research to what's feasible. "In the cave near Turin it is very easy to make precise measurements, as I have two labs within the cave," he says. But accurate measurements are much harder to make on research trips abroad, where he has only a month, at most, to do it all with equipment that isn't permanently installed. It is crucial, Badino says, to get to know the cave beforehand, so that "you know the technical difficulties that you are going to meet there, and you choose the measurements that you will be able to do," he says. Still, the challenges of the underground system are always limiting. "You try to do a hundred measurements, and if you come back with 30, you're happy."
A less than comfortable working environment
When carrying out research underground there are other problems besides instrument limitations. For one thing, you have to get down there. "In Italy, Spain, and France, the caves are very vertical, so you have to use single-rope techniques, similar to [mountain climbing]," says Badino. "In England, the caves are not vertical and [contain] a lot of water, so you have to use scuba equipment." At the best of times, caves present a cold and moist environment, with large water discharges, slippery floors, and bad rocks. "You need to be a specialist in [your] field and, furthermore, to be a caver," says Badino. But scientific speleologists need to be better than average, "because where a caver spends a few minutes for walking, you have to spend hours for data acquisition."
Mental strength is key to this job. "Underground, you can not see the top or the bottom [of the cave], and the cave tries to forbid your work," explains Badino. "You have to know that you want to go, in order to go." And caving is also far from being a risk-free activity. Compared to mountain climbing, accidents are less common, but they "are always very serious," says Badino. "The main difficulty is that you are often very far from the entrance (up to 20-25 hours of movement), and in case of [an] accident, you need more or less 10 hours of rescue for each hour of walk."
Finding a Niche Underground
Of course one doesn't just decide to become a caving scientist. "It is almost impossible to begin with the purpose of becoming a scientist [working] in caves," says Badino. One usually starts by being a caver. A few of those who fall in love with caving may then decide to study caves in detail, to specialise in this research field. "Caving clubs can give you a general preparation for caving -- how to move and what to do," says Badino. After that, the key is to get in touch with other scientific cavers, and find a niche for oneself.
So far, opportunities in underground research have been few, and most of them are in the protection of caves that are open to the public. Badino estimates that currently there are only a thousand researchers working on caves, while these make for a large, and almost unexplored system. This has its advantages. "There is a small competition to publish because the possible research fields are many, but the researchers are just a few, and very often they work in fields where they are not strong specialists, but only amateurs," says Badino. "On one side this is very good, because it is quite easy to find something new." But on the downside, one will often have to fight to get people interested in their work, and this means that few research grants are available. "[Breaking into this field] is difficult, but you can be the first to study a new planet," says Badino. "From this point of view the situation today is especially [exciting] because there is an increasing interest in the underground research fields."
But Badino believes that job market trends will change in the near future. "Only in recent times, due to electronics and dating-techniques developments, we are seeing that in the caves, small temperature variations and large fluids exchanges are at work. And that the caves can be considered as times archives, because all the external processes like glaciations, vegetation variations, and valley digging have left a track underground." The refinement of dating techniques should allow scientists to study caves over the world and read climate archives that go back millions of years.
Meanwhile, there is much reward to be gained for caving scientists. "It is a [great] emotion to work in galleries that you have discovered, in a completely new world," Badino says. "It is also an emotion to be in a cave you believe to know well, and for the first time to start to understand its way of working. It is another level of exploration."