The latest upcoming Super- El Niño has been all over the news recently. An event as big as the 1997/1998 Niño is foreseen and already the effects of extended forest fires in Indonesia and greater rainfall in coastal South America are being seen. With that in the back of our minds we, Hans van Aken, Kees Nooren and I set off last August for our flight to Quito, Ecuador. On our way from the airport to town we were impressed by the fresh road cuts with thick strata of volcanic ash. The Ecuadorian capital, the highest in the world, is situated in a valley surrounded by volcanoes on different levels, which makes for interesting detours when you try to find your way around. After some sight-seeing and getting used to the altitude (trying not to pant while climbing the tallest bell tower) we met up with Susana Leon and Manuela Ormaza from Quito Catholic University. Manuela, a student specialized in Páramo botany - the South American Alpine grasslands - would join our team up the mountains.
We aim to capture the impact of El Niño over the past century and further back in time and try to understand its drivers. The displacement of warm surface water from the west to east in the Pacific Ocean, which is what happens during an El Niño event, causes above normal evaporation and cloud formation that hit the Cordilleras of Ecuador and Peru. This is where our lakes come in. They capture the sediment and vegetation signals (pollen) washed in during an El Niño event … at least this is our hope! Sediment cores from the lakes possibly contain individual El Niño events back some 15 thousand years. But how to read such an archive? We set out to sample a whole range of lakes between about 3000 and 4200 m to collect reference material from all the possible indicators and potential proxies that our main lake archive, where a long sediment core had been collected earlier, would produce. What typically is a single phrase in a project proposal became a pretty tough expedition carrying our coring material on our backs along small muddy and steep Inca trails. It was soon clear that our original plans where too ambitious but we did collect a nice range of sites, meanwhile awed by the views and variety of the landscape.
It is clear that Ecuador is proud of its nature and is determined to protect its environment well, creating awareness also to the locals with billboards, road signs and generally very clean streets. Although a large part of the country’s economy now comes from oil production in the Amazonian lowlands and the black fumes of the trucks and busses put the “VW-gate” into perspective, they seem to be on the right track generally. That means that bringing your samples out of the country is not a minor issue. Armed with hopefully the right paperwork and local collaborators we managed to convince the authorities we were not smuggling orchids or hummingbirds and in the end were allowed to go.
Back in the lab in Utrecht we now look at the massive task of piecing together El Niño’s history and past activity from the sediment samples using the palaeoclimatologist toolbox. Anything that helps us to get a high resolution record of past temperature and rainfall will help and right now we look at pollen, diatoms, chemical elements and grainsize to read our history. Kimberley Hagemans is full time on the project, and together with MSc students (right now Martin Stekelenburg) we will keep you posted!