I guess I started thinking about ATO about around the year 2000. This is a scientific project with huge impact worldwide for science, but also for conservation. For me and some colleagues of the field of boundary layer research,

we have this, we can say this dream for more than two decades. The Germany proposal met here. Obviously this is sort of the dream of, well maybe not quite a lifetime, but the dream of a decade or almost two coming true.

ATO stands for Amazon Tall Tower Observatory, and it's focused on a 325 meter tall tower which we put here in the middle of the Amazon.

Basically the higher you go up, the broader the area, you get your influence in the air. And that is very important for us here. One of the main driving objectives behind the ATO research is to understand the global carbon cycle. So what we're trying to understand here is what is the role of the biosphere in regulating the atmospheric carbon cycle.

Does the Amazon forest right now act for instance as a sink that takes up carbon from the atmosphere, or is it maybe a source of carbon that goes into the atmosphere? This is a collaborative project between Germany and Brazil, with actually Brazil in a leading role, and the institutions that are involved are the National Amazon Research Institute, called INPA,

and the German Partner Institute is our institute, the Max Planck Institute for Chemistry and Mines. In the beginning, all the budget to build this tower would be German funds. But we were able to get Brazilian funds and share 50%, 50%.

The Brazilian institution, INPA, is strongly focused on research on the carbon cycle and on meteorology and micrometeorology, whereas our institution has an emphasis on aerosol chemistry and aerosol microphysics, as well as also on greenhouse gas composition and greenhouse gas concentrations in the atmosphere.

And at the end of 2010, we started the first measurements here of trace gases, which have ever taken place in this deep forest site, and that was great. And then, with the time in 2011, 2012, we have built up these first containers we have started to measure with this trace gas profile.

We had a first intensive operation campaign in the beginning of 2012, when also the aerosol measurements started to increase and grew up.

We want to understand how aerosol particles act as a source for cloud droplets and therefore also for rain. We also would like to understand the exchange between the biosphere here and the atmosphere above.

So we can understand better how the forest works in the relationship with the atmosphere. What is the gas exchange? What is the aerosol exchange? What is happening during the day, during the night? How is the forest coupled with the atmosphere? What is going in the wetter season, in the drier season?

A team of about 15 people putting together the tower over the course of five or six months.

After the foundation was built, basically it just kind of went together in a structure that the outer structure of the tower was built up, and it was more than 100 meters tall before they started putting in stairs.

We, of course, are very proud that this big tower, this big building,

is I guess the biggest one in South America or Latin America. It's there in the middle of the rainforest, and it's somehow surreal to see this happen in the middle of the forest.

The camp is amazing right now if we have four bathrooms, if we have two well-established stonemate houses where we can relax, where we can work. I think that the infrastructure of the tower has helped a lot of people who want to do what they want.

I have found that people have been able to use a good environment to work. The data which are generated at the other side, which we are measuring,

are directly transmitted to the labs and stored here. Before we had really campaigns which went there every week to make the download of the data and make a copy here in Manaus and send it to Germany.

I think it's the little spheres or something like that that make it really, really crunchy. It wasn't getting power. Okay, not my plan.

Yes, we do long-time measurements, and the other project is planned to stay at least 20, 30 years, so we are expecting to get a broad database, and over the years we can make a good statistic, we can get a deeper impression, also what is climate change doing with the forest, how is it reacting, and how is the system working.

And then we are here in an area of sustainable development. That means it is controlled by official institutions, and let's say for the next 10 years we do not expect any big change in the conditions of the pristine area.

The first steps are to equip the tower with the necessary instruments. The outer tower will be the biggest installation ever. It will be a very exciting work field, actually a challenge.

On the tall tower we will install some basic instruments on the top of the tower, using both inlet lines and instruments standing on top, because we want to extend our existing time series, so we will do sizing and also looking at the optical and chemical properties of the aerosol particles.

For me it is very interesting to see what is happening above 80 metres. Regarding the ozone question, I see at night sometimes an increase of ozone, and I cannot definitely see where is the source of ozone. Is it in 1 km height? Is it maybe only in 150 m height?

The measurements at ATO are hopefully going to help us answer actually what the role of long-range transport of atmospheric pollutants is in this region and in the world at large, how fast particles and pollution are produced,

how fast they are removed from the atmosphere, and how far this pollution can reach across the globe. I expect and hope that ATO will enhance our understanding for global climate systems, for regional weather systems also. It has always been a huge challenge, but what we are seeing now is that it is all coming together,

and hopefully when we have all the instrumentation installed at the tall tower, we will get this great data quality over many, many years from the ATO tall tower. Cheers!

Get to the platform at the end of each flight,

re-hook transfer to the other side. Not before or after, because certainly the stairs can be slippery, especially underneath the canopy.

How did the lightning run? Oh, not on top of the tower,

it is just a total rush from all the adrenaline and the excitement of coming up here. Today I am really impressed about this quick formation of the clouds. The sky is almost fully clouded, and we have the first precipitation events here, and that went more quickly than I expected today actually.

I think the work at ATO site, I think the work here at INPA, it is a perfect job to me, because I could combine all the things I love,

like the forest, the nature, and technology. Why in the world I could do that? All of these instruments humming away, and you open the other side of the door, and it is just jungle. This whole contrast was really interesting to me,

and I was excited to be in this new environment, and take part in the larger goals here, even if I am just working on the technical aspects, I am just trying to make sure everything is running. I feel lucky to be a part of it. We are able to include in the project the scientific interests of Brazil.

Yeah, I am very happy.

For me it is great, because I know that somehow we will prove that the Amazon rainforest is important for the world climate,

and that on the other side the climate changes are affecting the forest. When I went up the tower, for the first time in the very early morning, more or less at sunrise time, and I came at the level above the canopy 40-45 meters, and I have seen these banks of fog.