Other instruments are planned to be installed soon. The intensive field campaign period will take place in July.
]]>My name is Andrea, I’m a master’s student in physics from the University of Trento and I spent a couple of months in the Azores for my master’s thesis.
I’m studying the aerosol vertical structure from Pico, a remote island of the Azores, with a stratovolcano. An atmospheric observatory with meteorological observations is located at the top of the volcano. The position of that station is very particular, in fact thanks to its elevation it is situated in the so called “free troposphere”. And, for which reason should this matter? It matters, because it allows us to study air that comes from far away places, typically the North America. Within a certain approximation, we can say that the free tropospheric air is not influenced by the local emissions (I mean the emissions from the island itself) . This is motivated by the fact that the beginning of the free troposphere (called the boundary layer) is characterized by a thermal inversion (Figure 1). Thanks to the thermal inversion, the air masses do not easily exchange components at the boundary layer. The identification of the boundary layer is pretty easy if there are low clouds. In fact in that case the height at which the clouds disappear corresponds to the beginning of the free troposphere.
Figure1: The caldera of the Pico volcano with a visible thermal inversion as seen by the confined clouds.
However every time we speak of the atmosphere, we must keep in mind that the situation could be really dynamic, especially if you are on a remote island in the middle of nowhere, exposed to every kind of perturbation. For this reason, it is important to characterize the vertical structure of the atmosphere and to understand within which conditions measurements done at the observatory can be considered to be independent from local emissions.
How do I do this vertical characterization?
In theory it is pretty simple; I put all my instruments in a backpack and hike (Figure 2), starting from an elevation of about 1200 meters above sea level to the Pico Mountain Observatory (2200 meters above sea level). In my backpack, I have an instrument that collects pressure, temperature and humidity, although it is pretty small I usually put this instrument into a big case to protect it from direct exposure to solar radiation. I also have a nephelometer, this is the biggest instrument, and it measures the light scattered from the particles present in the atmosphere (i.e. Aerosol, dust, etc…). Moreover I carry a particle counter which allows me to measure the concentration of particles with diameters above 0.3 μm and 0.5 μm. This instrument is especially useful because it allows me to distinguish between the dust particles, generally bigger than 0.5 μm, and the combustion aerosols that are generally smaller. Finally I have a sunphotometer, an instrument that measures the intensity of the sunlight that reaches the detector. In this way, it is possible to have an idea of the quantity of haze present into the atmosphere above the observer. In addition to all these instruments, I also use a GPS in order to track my position and my elevation.
Figure 2: Andrea Baccani with his measurement backpack
A Strange Event
Recently, we noticed a very interesting event that I will describe briefly without much technical detail. On a clear day, with clouds well below the top of the mountain we noticed something unusual. Thin grey layers above the clouds are often visible and are an indication of the presence of some kind of particulate, like aerosol from anthropogenic emission or biomass burning, dust, etc… However on this specific day we noticed a particularity: the layer above the clouds was composed of three well-defined sub layers (Figure 3). This was the first time we observed an event like that and it would be very interesting to understand why that triple stratification happened and if the composition of the layers was different or not.
Figure 3: A photo of the aerosol layers above the clouds. High contrast was used to clarify the image (blue box).
The most interesting part is that these three layers were also present in my profiles measurement and this provides us with good informations about the height and the thickness of the layers.
To show this to you, I will use a couple of graphs. The first graph is the particle concentration profile (Figure 4). On the vertical axis there is the elevation while on the horizontal axis there are the particle concentrations. The particles with a size above 0.3 micron are shown in green and those above 0.5 micron are shown in blue. The first thing to notice is that both of the signals have a clear decrease around 1500 meters. This is likely associated with the passage into the free troposphere and is supported by the temperature profile that indicates an inversion at the same height (not reported here). Above the boundary layer there are evident variations in the signal of small particles concentration,while the signal for the bigger particles seems to be pretty stable (around 0.3 particles for cubic centimeter). Because most dust particles are bigger than 0.5 microns we may exclude the presence of dust in the layers. This is pretty important because dust is generally the most abundant type of remote atmospheric aerosols.
Figure 4: The particle concentration profile observed from the Pico Mountain profile measurements.
Now we can notice that at the moment of the measurements, the first layer was approximately 450 meters thick, starting at a height of 1600 meters and ending at 2050. The second starts around 2100 meters and ends at 2250 meters and for the third later we can observed only the beginning at approximately 2300 meters above the sea level. Clearly the identification of the position of the layers is subjected to some uncertainties that we estimate to be approximately around 50 meters.
In order to confirm these observations we will look at the nephelometer data shown in the graphs below (Figure 5). The elevation is again on the vertical axis and the scattering coefficient is on the horizontal axis. The scattering coefficient, is a measure of the light scattered intensity (it corresponds to the size and the number of particles that scatter the light). In this data the three layers are somewhat less evident because the level of noise is higher, however their position corresponds quite well to those measured with the particle counter.
Figure 5: The aerosol scattering profile observed from the Pico Mountain profile measurements.
In summary, we measured the three aerosol layers above clouds with two different instruments. These measurements provide evidence to conclude that what we measured is effectively what we saw looking at the horizon and was not an artifact. However at this moment, this is only a preliminary analysis that requires further technical investigations in order to be confirmed. Moreover, it will be interesting to analyze additional data collected at the station in order to obtain more information about these layers and maybe understand their composition and origin. So, stay tuned because maybe some updates will come!!!
See also – Portuguese News about this study
]]>Publican em 4 de setembro de 2015 (English Version Available)
Escrito por David Borges, Ilha Maior
A estação ‘Pico Nare’ que está colocada na cratera da montanha continua a ser um observatório de excelência para estudar a poluição atmosférica que circula no Atlântico Norte.
Essa importância foi sublinhada em declarações a Ilha Maior por Claudio Mazzoleni. O cientista diz que a estação do Pico é única e está para a Europa como a do Hawai está para o continente americano: “São como sentinelas que intercetam a poluição que vem do oeste. No caso do Pico a estação é um ponto no meio do Atlântico, uma torre única que permite acesso à troposfera livre, possibilitando o estudo das propriedades dessas partículas.”
A cientista Lynn Mazzoleni, que nos últimos anos tem utilizado o observatório para desenvolver vários tipos de estudos, adianta que apesar das dificuldades sentidas para garantir o necessário financiamento o observatório não irá fechar. Segundo a cientista da Michigan Tech (universidade no michigan), além do interesse dos Estados Unidos em tudo o que se relaciona com o clima, Portugal também está atento ao observatório existindo inclusivamente um grande grupo ligado à investigação da atmosfera e da química que tem uma proposta para utilizar a estação como local privilegiado para desenvolver vários estudos atmosféricos.
“Há sempre coisas novas para descobrir e queremos saber mais e mais. Até já agora vimos a transformação de partículas de uma forma que nunca tinha sido observada antes porque a morfologia muda com o transporte e suspeitamos que isso é uma consequência das nuvens”, diz a cientista norte americana acrescentando que entre os vários estudos em curso na estação fundada em 2001 por Richard Honrath “os cientistas tentam identificar o segundo componente na atmosfera que contribui para o aquecimento e que pode constituir uma das grandes causas do aquecimento global resultante de incêndios ou de outros tipos de combustão”.
Além deste trabalho um dos estudos em curso atualmente na ‘Pico Nare’ está a ser desenvolvido por um aluno da universidade italiana de Trento.
O trabalho consiste em subir e descer a montanha com instrumentos de bolso para melhorar a precisão das medições, tentando caracterizar a composição vertical dos aerossóis na atmosfera
O estudo faz parte da tese final de Andrea Baccarini, tendo o aluno optado pelo Pico para, não trabalhar apenas em laboratório: “A estação do Pico é o local ideal para um estudo deste tipo por ser um local remoto fora das grandes cidades onde é possível fazer as medições na troposfera livre, o que permite ter a certeza que o que medimos não é de produção local da ilha, mas proveniente do norte dos Estados Unidos, Canadá e Alasca onde há muita falta de água e as partículas que vão para a atmosfera chegam a atingir esta ilha.”
O aluno da universidade italiana explica que seria possível realizar o trabalho mesmo que não houvesse a estação do Pico, porque os instrumentos podem ir no bolso. No entanto esclarece que a ‘Pico Nare’ contribui para de forma mais precisa comparar e confirmer as medições com as dos instrumentos de bolso.
Andrea Baccarini não sabe quando é que terá conclusões para apresentar, mas espera que até final do ano ter conseguido trabalhar todos os dados recolhidos e apresentar os resultados o mais rápido possível.
]]>Published on September 4, 2015 (Versão em Português Disponível)
This story was translated using Google Translate.
Written by David Borges, Ilha Maior
The station ‘Pico NARE’ that is placed in the mountain crater remains an observatory of excellence to study air pollution that flows in the North Atlantic.
This importance was underlined in a statement to Ilha Maior by Claudio Mazzoleni. The scientist says that Pico is unique and is to Europe as Hawaii is to the American continent: “They are like sentinels that intersect each other pollution coming from the west. In the case of Pico it is a point in the middle of the Atlantic, a unique tower that provides access to the free troposphere, allowing the study of the properties of these particles. ”
The scientist Lynn Mazzoleni, which in recent years has used the observatory to develop various types of studies, said that despite the difficulties to ensure the necessary funding the observatory will not close. According to the scientist at Michigan Tech, in addition to the United States’ interest in all that relates to the climate, Portugal is also aware of the Observatory; there is even a large group linked to the investigation of the atmosphere and the chemistry that has a proposal to use station as a privileged place to develop various atmospheric studies.
“There are always new things to discover and want to know more and more. So far, we have already seen the transformation of particles in a way that had never been observed before because the morphology changes with transport and we suspect that it is a consequence of the clouds,” the North American scientist says. Adding that among the various ongoing studies at the station founded in 2001 by Richard Honrath, “scientists try to identify the second component in the atmosphere that contribute to warming and that can be a major cause of global warming resulting from fires or other types of combustion.”
In addition to this work, one of the currently ongoing studies at the ‘Pico NARE’ is being developed by a student of the Italian University of Trento.
The work consists of going up and down the mountain with portable instruments to improve the accuracy of measurements, trying to characterize the vertical composition of aerosols in the atmosphere.
The study is part of the final thesis for Andrea Baccarini, the student who opted to work at Pico and not only work in the laboratory: “Pico is an ideal place for such a study because it is a remote location outside the major cities where it is possible to make measurements in the free troposphere, which allows to make sure that what we measure is not spot on the island production, but from the northern United States, Canada and Alaska where there is a lot of lack of water and the particles that go to atmosphere get to reach this island. ”
The student of the Italian university said it would be possible to carry out the job at Pico Mountain, because the instruments can go in your backpack. However, he clarifies that the ‘Pico NARE’ station contributes to more accurately compare and confirm measurements with those of portable instruments.
Andrea Baccarini does not know when he will have to present conclusions, but he expects that by the end of the year have been able to work all the collected data and he will present the results as soon as possible.
See also – Story by Andrea Baccarini
]]>
Professor of Chemistry at Azores University
Dr. Fialho is a founding collaborator of the Pico Mountain Observatory. He has been measuring black carbon at the site since 2001.
Dr. Fialho is the primary point of contact for activities at the Pico Mountain Observatory.
]]>To learn more please see: Dzepina et al., ACP, 2015.
]]>Sometimes our work at the Pico Mountain Observatory is both mentally and physically challenging, but it is always rewarding. Since we arrived almost two weeks ago, the weather has been fairly uncooperative. We had a few days of warm sunshine, kindly reminding us of why we are here, “to sample the air of the marine free troposphere far away from direct emission sources”. From our previous work at this remote location, we recently published two technical papers about our observations of soot morphology and aerosol chemistry. These technical observations inform the scientific community about the effects of long-range transport on the aerosol mainly from North America.
This year’s fieldwork is now underway and just as we picked up some momentum, the weather became difficult to predict. This means, that sometimes we will not be able to do our work upon reaching the Observatory and sometimes traversing up and down the mountain is dangerous and especially so with high winds and rain. This year is particularly special, because we are hosting a guest scientist from Trento Italy, who’s planning to collect some very special mountain profile measurements by carrying several small instruments on his back. Thus, sitting in the apartment and waiting for ideal conditions is absolutely out of the question.
This week, we selected a day with the best chance for dry conditions during most of the day and we decided to go for it. By the way, did I mention the mountain hike is quite strenuous with difficult footings even for experienced hikers and we scientists are not mountaineers. When we arrived at the Casa da Montanha to check-in, Isabel warned us the mountain will not likely be very good. Isabel has been working at the Casa da Montanha for many years and she has seen a number of injuries, thus sometimes she is a bit more cautious than we are. Besides on this day, we were anxious to get going to collect our measurements and finish necessary repairs at the observatory and so we said, “ok” and went ahead.
We started our hike and then almost immediately hit cool cloudy conditions, which seemed to persist. This was a bit disappointing because the mountain profile measurements are compromised by cloud drops. Luckily for us, the cool cloud appeared to be low on the mountain and so we charged ahead into the sunshine a bit further up. The sunshine and lack of clouds were very inspiring and ideal for the mountain profile measurements. So, we discussed turning on the backpack instrumentation once again. At this moment, a newly married couple from the US overheard us talking and inquired about our pack. They were impressed with our story and so we charged ahead with vigor.
The rest of the hike was smooth with clear skies and ample sunshine. We reached the summit caldera and felt happy to have good weather to do our work. Although a short while later, while I was fully immersed in the electronics of the pesky hi-volume air samplers, the air rapidly cooled and increased in humidity. Then suddenly, it was raining! Because I hadn’t noticed the weather change, all of the electronic boards of my precious high-volume air samplers were exposed to the elements. The effort to put them away and protect them from water takes only about 30 minutes – which feels like a long time in cold wet rain. As I worked, the rain increased and I started to feel really frustrated with the design of the sampler, which seemed excessively unfriendly. To dry out and calm down, I went into the tiny Observatory. It’s a small instrument-dedicated space with lots of sensitive instruments and plenty of obstacles to bump into. My favorite spot is the low ceiling between the two tiny rooms.
After my colleagues finished working outside in the cold wet cloud, we reconvened inside and started talking about the small things to be done inside before leaving. This was disappointing, because we had just recently arrived and didn’t accomplish much yet. Meanwhile, the weather was consistently getting worse, as it sometimes does in mountain environments, and so we knew that it was time to go. We would be cold and wet from the dense cloud in just a short time and we would be hiking down a steep mountain for at least two hours. That’s two or three hours from hot showers, cold beers and tasty Azorean treats. It’s those things that motivate us to get down off the mountain, despite the very unpleasant and sometimes dangerous conditions.
To distract our minds from thinking about the weather and all of the things that we didn’t accomplish, we often talk about the new language oddities that we’ve picked up in our recent observations of the locals. Portuguese is an interesting and complicated language, especially for non-latin language speakers. But in the Azores, the words don’t sound at all like they do on Babbel.com. They offer only Brazilian Portuguese and although there are lots of differences between European and Brazilian Portuguese…I suspect there are even more differences between the Azorean and Brazilian Portuguese as well. In most conversations, I get that cute little smile that tells me my effort is appreciated, but perhaps it will be easier for them to speak English with me.
This effort to mentally distract myself is very important, because honestly, I’m sometimes feeling insecure with my footings and just enough uncomfortable that I am worried about getting down off the mountain safely. Once down, all is well and we focus on recovery food and drink. Then after the basic human needs are fulfilled, we wonder when will we go back up and how will the weather be.
Where is the famous Azores high pressure? That high pressure is optimal for our work for several reasons, including: the warm sunshine & predictable nice days, the good downward transport of long-range transported aerosols form the upper troposphere and the ability to collect aerosol without compromising the instruments or the samples. On the contrary, the low pressure brings wet weather, unpredictable and dangerous storms, upward fluxes of clean lower troposphere air masses and high humidity or suspended droplets that potentially damage our instruments and compromise our samples.
After two days of waiting, another potentially good hiking day presents itself. We hiked up slowly, still a bit stressed from the time before. Luckily, the weather was stable and we were able to finish the things we set out to accomplish a few days before and even tackle a few more. The descent on that day was especially good with stable conditions and a good sense of accomplishment.
Publicado em 16 de agosto de 2013 (English Version Available)
Escrito por David Borges
A Universidade Tecnológica do Michigan, com o apoio da Fundação Nacional de Ciência, do Departamento de Energia dos Estados Unidos e da NASA, está a desenvolver dois novos projetos na estação Pico Nare instalada no topo da montanha do Pico para estudar o efeito climático dos aerossóis. Os projetos, com dois e três anos de duração, baseiam-se no estudo das propriedades químicas e também das características óticas das partículas como a cor e a forma que determinam a sua interação com a luz solar.
Na estação colocada desde 2001 na cratera da montanha os especialistas esperam observar aerossóis provenientes do continente americano, resultantes por exemplo do fumo de grandes incêndios localizados sobretudo na parte norte do continente, com origem no Canadá e/ou Estados Unidos da América.
Os aerossóis são partículas muito pequenas suspensas no ar, resultants de combustão ou outras atividades do ser humano e que podem ter uma duração entre 1 a 2 semanas, dependendo da sua origem e das condições atmosféricas. As partículas interagem com a luz solar e dependendo das suas características tanto podem refletir a luz de volta para o espaço e assim arrefecer a atmosfera ou, se forem pretas ou castanhas, absorver a radiação e contribuir para aquecer a atmosfera.
Os estudos que estão a ser realizados por Lynn Mazzoleni, Claudio Mazzoleni, Kendra Wright e Lorentyna Harkness são um desafio para os cientistas que realçam as excelentes condições proporcionadas pela montanha do Pico. Segundo Lynn Mazzoleni ao Pico pode garantir condições que não existem noutra parte do mundo: “Escolhemos o Pico porque a montanha permite-nos ficar com frequência acima das nuvens, possibilitando o estudo das propriedades dessas partículas. Este vulcão tem uma forma muito interessante porque o ar circula a montanha em vez de ser empurrado para fora, permitindo que no topo contactemos com a troposfera livre. É como uma ligação que há na atmosfera e que permite que tudo esteja bem misturado e quando a poluição a atinge prolonga- se durante um pouco mais de tempo sendo transportada através dos continentes.”
A cientista da Universidade do Michigan realça igualmente a qualidade ambiental do arquipélago, sublinhando que esse é um fator fundamental para o resultado final do estudo: “Além da forma especial da montanha do Pico, o facto do ambiente cá ser muito limpo impede que sejamos influenciados pela poluição local, que por si só é escassa, facilitando o nosso trabalho porque os instrumentos são muito sensíveis e é importante que não sejam influenciados pela poluição local”.
Embora algumas das medicos que estão a ser realizadas ofereçam resultados imediatos, também há amostras recolhidas no topo da montanha que os especialistas têm de levar para análise na universidade e só depois dos dados tratados e recolhidos poderão tirar conclusões.
]]>Kendra Wright, Lorentyna Harkness, Claudio Mazzoleni and Lynn Mazzoleni were interviewed by David Borges, a local newspaper reporter in Madalena, in July 2013. Here’s the newspaper story that resulted from our talk.
Published on August 16, 2013 (Versão em Português Disponível)
This story was translated using Google Translate.
Written by David Borges
]]>