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GeoTalk: Research reflections and lessons learned from Pinhas Alpert

GeoTalk: Research reflections and lessons learned from Pinhas Alpert

GeoTalk interviews usually feature the work of early career researchers, but this month we deviate from the standard format to speak to Pinhas Alpert, professor in geophysics and planetary sciences at Tel Aviv University and recipient of the 2018 Vilhelm Bjerknes Medal. Alpert was awarded for his outstanding contributions to atmospheric dynamics and aerosol science. Here we talk to him about his career, research, and life lessons he has learned as a scientist.  

Thank you for talking to us today! Could you introduce yourself and tell us a little more about your career path?

I was born in Jerusalem, Israel on 28 Sept 1949. I received my BSc (Physics, Math & Computers) and MSc (Physics) as well as my Phd (Meteorology) at the Hebrew University of Jerusalem (1980; supervised by late Prof. Yehuda Neumann, Head of the Department of Meteorology).

Then I did my post-doc studies at Harvard University (US) with Professor Richard Lindzen (1980-1982) and got a position at Tel Aviv University in 1982.

I served as the Head of the Porter School of Environmental Studies, Tel-Aviv University, Israel, from 2008 to 2013, following three years as Head of the Department of Geophysics and Planetary Sciences also at Tel Aviv University.

My research focuses on atmospheric dynamics, climate, numerical methods, limited area modeling, aerosol dynamics and climate change. As part of my PhD, I built an atmospheric model, which is used in Belgium (LLN) and Finland (UH) for research.

I’ve published three books, and I am the co-author of more than 347 articles (240 peer-reviewed; 107 in books).

Some more recent work includes developing with my colleagues a novel way for monitoring rainfall using cellular network data. From this method we were able to create a new kind of advanced flood warning system.

I also developed a novel Factor Separation Method in numerical simulations. This methodology allows researchers to calculate atmospheric synergies, and has been adapted by many groups worldwide.

I established and head the Israel Space Agency Middle East Interactive Data Archive (ISA-MEIDA). Currently it is called the Israeli Atmospheric and Climatic Data Center (IACDC), which provides easy access to geophysical data from Israel and across the globe. I served as co-director of the GLOWA-Jordan River BMBF/MOS project to study the water vulnerability in the E. Mediterranean and also served as the Israel representative to the IPCC Third Assessment Report Working Group 1.

In addition to my research projects and positions I have supervised 42 Master students and 23 Doctoral students; some of them have become professors themselves in universities in Israel and abroad.

My current group consists of nine students as well as four post-docs and researchers.

I married my wife Rachel (RN) in 1971 and we have eight children and sweet grandchildren (not to count).

This year you received the 2018 Vilhelm Bjerknes Medal for your outstanding contributions to atmospheric dynamics and aerosol science, most notably your involvement with the Factor Separation Method and novel monitoring systems.

For those readers who may not be so familiar with your work, could you give us a quick summary of your research contributions and why it’s important?

“Remember to do the research that you love the most.” (Credit: Pinhas Alpert)

The Factor Separation Method, first introduced in 1993, allowed scientists to compute the separation of synergies (or interactions or non-linear processes) among several factors for the first time in a quantitative approach.

This allowed researchers to compare for the first time different factors which contribute to some important processes like: heavy rainfall, floods, cyclone deepening, and model errors. The methods have now been applied in many areas of research, including environmental studies, paleoclimatology, limnology, regional climate change, rainfall analysis, cloud modelling, pollution, crop growth, and forecasting.

As to our novel method for monitoring atmospheric moisture: science today does not really know well enough how rainfall or moisture are distributed in the atmosphere.

This is true for all the world but it is particularly so over semi-arid or mountainous regions. For instance over Israel, a semi-arid region, we have about 100 rain gauges, while data from three cellular companies provide us with about 7000 cellular links from which we can calculate distribution of rain in real-time. Many severe flood events particularly over the semi-arid area of S. Israel have not been monitored at all by the classical approached including rain gauges and radar.

My colleagues and I developed a way to monitor such atmospheric conditions that taps into cellular communication networks (the network that lets us use our mobile phones for example). These networks are highly sensitive to the effects of weather phenomena and are widely spread across the world. By using data recorded by cellular communication providers, we found that these networks can provide important information on dangerous weather conditions.

For example, in one study published in the Bulletin of the American Meteorological Society we demonstrated that the technique could be used to monitor dense fog events. This is very important since there are no alternative methods to monitor fog on roads and highways, and furthermore they contribute to hazardous weather in which often hundreds of cars may be involved.

At the 2018 General Assembly, you gave a medal lecture on your personal perspective on the evolution of atmospheric research over time. What are some of the biggest lessons you have learned as a researcher?

My take-away messages were:

It seems impossible to predict which research will become a scientific breakthrough because,

  1. the message from your research came too early. For example, the Italian scientist Amedeo Avogadro first proposed the existence of a constant number of molecules in each kilomole of gas and calculated this number (6.022×1023). However, he was ridiculed for it, and only after he passed away was it accepted by the scientific community. Now every student must learn the Avogadro number in any basic thermodynamics course.
  2. the message was not clear or strong enough: When we are sure about our finding we must be strong in our statements and not too modest. Otherwise, the scientific community assumes that what we claim in our article is only a conjencture.
  3. the message was not given the right exposure. For example, in 1778-9 the French scholar Pierre-Simon Laplace was the first to develop the mathematical terms the Coriolis Force, an important term in physics that explains air acceleration due to Earth’s rotation. However, it was until 60 years later that the French mathematician Gaspard-Gustave Coriolis gave these terms their physical meaning, i.e. that air-parcels in the Northern Hemisphere for instance turn to the right due to the Earth rotation. And, this was the main reason why these terms were called after Coriolis and not after Laplace.

 

Pinhas Alpert receiving the Vilhelm Bjerknes Medal at the EGU Awards Ceremony during the 2018 General Assembly. (Credit: EGU/Foto Pfluegl)

I also discussed whether researchers should invest their time in a concentrated topic, or spread their interests. A common question in atmospheric research, which is particularly bothering early career researchers, is which of these primary three directions should they choose to follow: 1. theoretical approach; 2. analysis of observations and 3. Employ atmospheric models.

One option is to spread your efforts in two or three of these directions. while the more easy approach is often to focus on only one of these three routes. My take-away message during my talk was that, while it certainly more difficult to spread your research to 2-3 of these pathways, it is a very personal decision. There is no right answer that applies to everyone, and your choice depends very much on your personal preference. Remember to do the research that you love the most.

And the other most important take-away message for success is hard work. As Thomas Edison once said in an interview in 1929, “None of my inventions came by accident. I see a worthwhile need to be met and I make trial after trial until it comes. What it boils down to is one per cent inspiration and ninety-nine per cent perspiration.”

Recently, the IPCC released a special report on the consequences of global warming and the benefits of limiting warming to 1.5ºC above pre-industrial levels. You had mentioned that you served as the Israel representative to the IPCC Third Assessment Report Working Group I. What would you say were some key lessons learned from contributing to an IPCC report? Do you think it is important for researchers to be involved in the policy process?

One of the most amazing things I have learned from my participation there was how much politics and debate are involved there. There are a lot of negotiations between the representatives of the various countries, who sometimes spend hours on the wording of sentences.

Yes, it is very important for researchers to bring the messages from their work to decision makers. However, this should only be done when you are convinced that your results are important for the society. Hence, it is my opinion that early career scientists should focus more on promoting their science and be less involved in the policymaking process. Without a strong scientific backing, it may interfere with your research. Again, here as well, the decision should be strongly based on your personal feelings.

Interview by Olivia Trani, EGU Communications Officer

Imaggeo on Mondays: A pink and blue evening

Imaggeo on Mondays: A pink and blue evening

At sunset, the light travels a longer path in the atmosphere to reach our eyes than when the sun is high in the sky. At this time of the day, the light is more subject to scattering, as it interacts with more air (molecules and particles) before reaching our eyes, which explains why the sun is much less luminous and can be observed directly without being dazzled.

The sun appears redder because among the visible colours it emits, the blue radiation has been scattered by air molecules before this blue light reaches the observer. Indeed, the Rayleigh scattering theory says that the blue light (wavelength near 400 nm) is 16 times more scattered than the red light (wavelength near 800 nm). So the blue light is deviated outside the sun direction and only the remaining red light reaches the observer looking in the sun direction. This phenomenon also gives the blue colour of the sky when we look elsewhere than the direction of the sun.

Clouds consist of particles of liquid or solid water that are much larger than air molecules. It is then the Mie scattering theory that applies. This scattering favors no colour, which explains the milky colour of the clouds during the day. The clouds have the same colour of the solar radiation that strikes them. They therefore take a red colour at sunset and sunrise.

The night I took this photo, the beauty of the show was tinged with sadness: I came to the Pic du Midi Observatory in the Pyrenees (2800 m altitude) to observe the stars, not the clouds! This night of stars observation was a very great birthday present from my lab colleagues.

Luckily, the ceiling of the cloud layer lowered a little and the night was clear enough. The next morning, at dawn, the sea of ​​clouds confined in the valleys also offered a grandiose spectacle.

By Claudine Vanbauce, Université de Lille, Laboratoire d’Optique Atmosphérique, France

If you pre-register for the 2019 General Assembly (Vienna, 07–12 April), you can take part in our annual photo competition! From 15 January until 15 February, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: The ash cloud of Eyjafjallajökull approaches

Imaggeo on Mondays: The ash cloud of Eyjafjallajökull approaches

This photo depicts the famous ash cloud of the Icelandic volcano Eyjafjallajökull, which disrupted air traffic in Europe and over the North Atlantic Ocean for several days in spring 2010. The picture was taken during the initial phase of the eruption south of the town of Kirjubæjarklaustur, at the end of a long field work day. Visibility inside the ash cloud was within only a few metres.

The eruption was preceded by years of seismic unrest and repeated magma intrusions. A first effusive fissure opened outside the ice shield of the volcano at the end of March 2010, followed by an explosive eruption in the main crater of the volcano in April 2010.

Iceland was well prepared for the eruption – the rest of the world obviously was not. The region around Eyjafjallajökull is sparsely populated, residents were prepared days before the eruption and the evacuation went smoothly. However, the grain size of the ejected volcanic ash was fine enough so that the unfavourable and unusual wind direction during these days transported the ash all the way to Europe and led to air space closures almost all over the continent.

By Martin Hensch, Nordic Volcanological Center, University of Iceland (now at Geological Survey of Baden-Württemberg, Germany)

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

An overnight train view of China’s Anthropocene – Part 1

An overnight train view of China’s Anthropocene – Part 1

The nighttrain from Shanghai to Beijing is a comfortable affair. The train is new and clean. My travel partner and I can charge our phones and relax on soft beds. The railway is almost frictionless, and overall the experience is similar to any ride in the West. But outside, as the vehicle roars through the early night, things become increasingly hazy. As we reach further out from the Shanghai metropolis there is a slow realisation that the urban air-polluted luminous glow would not be left behind.

For those who have yet to visit China, it’s hard to truly convey the extent of the air pollution problem. During our time in Shanghai the smog was all encompassing; we could feel it settle on our skin and invade our lungs with every breath. Outdoors there was no escaping it. The Chinese air pollution forecast designated the risk level ‘moderate,’ and we wondered what ‘high’ would entail.

Inside the train we lay on opposite bunks. I fixed the window blind ajar to keep a sleepy eye on nighttime tree tops and apartment blocks as we dart by. We passed endless residential towers as we edged by cities we would never become familiar with, some of which appear desolate, almost entirely unlit, but I can’t imagine for long. Once we passed directly under a giant coal fired power station and by countless fields illuminated in the haze by nocturnal agriculture. There are trucks loading at 3 a.m. Along this 1200 km stretch – think Paris to Madrid – the foggy dim light rarely ceded.

This true-color image over eastern China was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS), flying aboard NASA’s Aqua satellite, on Oct. 16, 2002. The scene reveals dozens of fires burning on the surface (red dots) and a thick pall of smoke and haze (greyish pixels) filling the skies overhead. Credit: NASA (via Wikimedia Commons)

My traveling companion is a children’s doctor. She raised her concerns: what chance do children born in these cities today have of living long healthy lives? Will they live full lives breathing in this industrial gunk? She explained to me that respiratory diseases kill because of chronic inflammation in the lungs, similar to that experienced from exposure to cigarette smoke. Such inflammation can in time lead to reduced lung function and, consequently, increased pressure on the heart due to less oxygen intake. Then, as the heart works harder to introduce the oxygen the body needs, it can fail, leading to premature death.

Estimates on health issues relating to long-term exposure to air pollution in China are hard to come by. It’s also hard to assess how dangerous such exposure is, but it’s likely China will experience an epidemic of respiratory related illnesses in the near future. One recent study reported that the Chinese population will suffer about 1.6 million premature deaths each year due to air pollution. As well as the human cost of lost loved ones, these air pollution related health risks will become a tremendous financial burden on the national health system. In 2007, The World Bank estimated that the annual health cost of outdoor urban air pollution in China for 2003 was between 157 and 520 billion Chinese yuan, around 1-3% of China’s gross domestic product.

However, this year China announced it would, for the first time, introduce a human health air pollution watchdog. According to Chinese officials, this is the first attempt by the national government to address how pollution affects public health. One day, scientists will be able to report on how generations born today can benefit from such endeavours. But for now, the future remains uncertain.

This is Part 1 of a two-part series on the impact of air pollution in China and the country’s steps to usher a clean era for the 21st century. Keep an eye out for Part 2, appearing next week on Geolog.

By Conor Purcell, a Science & Nature Writer with a PhD in Earth Science

Conor Purcell is a science journalist with a PhD in Earth Science. He is the founding editor of www.wideorbits.com and can be found on twitter @ConorPPurcell and some of his other articles at cppurcell.tumblr.com.

Editor’s note: This is a guest blog post that expresses the opinion of its author, whose views may differ from those of the European Geosciences Union. We hope the post can serve to generate discussion and a civilised debate amongst our readers.