My life in science, by Julián Adem

The National Autonomous University of Mexico produced the book 'Forjadores de la ciencia en la UNAM: conferencias del ciclo Mi vida en la ciencia, mayo-agosto de 2003 (UNAM, Coordinación de la Investigación Científica, 2003) which published lectures from the series of events in 'My life in science' held between May and August 2003. The 'My life in science' series honoured those at the UNAM who were 'Shapers of science'. We give an English translation of the lecture given by Julián Adem.

My life in science, by Julián Adem.


The distinction that I have just received makes me reflect on the people and factors that determined the initial course of my life, and I want to remember them to share this recognition with them.

My parents, Jorge Adem and Almas Chahín, came to Mexico from Lebanon, choosing the city and port of Tuxpan to start their family. My brothers, José and Antonio, my sisters, María Elena, Labibe, Alicia and Esbaide, all born in Tuxpan, with whom I shared the example and teachings of our parents, in the very provincial environment of that city, which in those days lacked good communications with the rest of the state and the country.

In 1938 an event occurred that changed my life, as well as that of many other Tuxpenos: Professor Manuel C Tello came to Tuxpan from Jalapa and established the secondary and high school that today bears his name, and which since then has depended on the Universidad Veracruzana. I was from the fourth generation of students, and received a solid preparation there, thanks to the commitment and great academic and human quality of teacher Tello and the other professors, most of whom were professionals who pursued their careers in Tuxpan and dedicated a good part of their time to teaching.

With a clear vocation towards the exact sciences, my brother José and I decided to study Engineering, at the then National School of Engineers of the National Autonomous University of Mexico (UNAM).

José left first, in 1941, and I in 1943. When we found ourselves in the university environment, we discovered that the then incipient Mathematics career existed in the Faculty of Sciences, whose studies were also located in the same Palacio de Minería, headquarters of the traditional National School of Engineers. We decided to study Mathematics simultaneously with Engineering. Subsequently, we received scholarships to study a doctorate abroad and we returned to Mexico at a moment of historical importance for the nation: the change from the National Autonomous University of Mexico to the brand new Ciudad Universitaria.

Unfortunately, my brother José passed away in 1991; he, however, left his enduring contribution to mathematics worldwide and created the Department of Mathematics of the Centre for Advanced Studies of the National Polytechnic Institute at the national level.

The environment of Ciudad Universitaria was favourable for the development of scientific research, which is the basis of teaching at the postgraduate level. Full-time researcher and professor positions were established, research institutes and centres began to consolidate, and new ones were created.

With several choices in my life, I have been fortunate to choose the right path to follow in scientific research and, through mathematics, to develop models that try to explain the causes and effects of climate change, and possibly predict them.

I belong to a generation of researchers and teachers who, upon returning to Mexico, with a new research discipline, had to devote themselves to the task of creating the infrastructure that would allow them to move forward, creating research institutes and centres, as well as new chairs, and training new researchers and professionals, who over the years have been consolidating these institutions. The beginning was difficult but undoubtedly the conditions that existed in the new Ciudad Universitaria were and continue to be propitious for progress.

In 1957 and 1958, the International Geophysical Year was held, an unparalleled event in the history of Earth Sciences, and in which Mexico played a very decent role worldwide, providing geophysical data on the oceans, continents and the atmosphere within its territory, through very close collaboration between university institutes and government agencies dedicated to these disciplines, such as the Navy, Agriculture, and Communications and Transportation Secretariats. In addition, joint projects were started, such as the establishment of a national tide gauge network. In January 1958, the scientific expedition to Socorro Island, in the Revillagigedo Archipelago, was carried out, which I had to lead, and in which researchers were from the Institutes of Geophysics, Geology, Biology and Geography of the UNAM, and the Secretary of the Navy.

The space age began in the International Geophysical Year, when artificial satellites were put into orbit for the first time, which are traveling observatories that have expanded knowledge of planet Earth and outer space with the large amount of data obtained.

From then on, Geophysical Sciences, and particularly Atmospheric Sciences, began to consolidate in Mexico and in the world. Starting in 1971, Consejo Nacional de Ciencia y Tecnología (CONACyT) was created, where the Indicative Programme on Meteorology was organised, to promote the strengthening and development of meteorological services and the teaching of Atmospheric Sciences in the country, at the undergraduate and postgraduate level. An inventory of educational institutions showed that at that time only master's studies in Geophysical Sciences existed, with an option for Atmospheric Sciences, at the Faculty of Sciences of the UNAM.

Students with degrees in Physics, Mathematics and Engineering were enrolled in this master's degree.

The inventory indicated that Mexico lacked undergraduate studies in Atmospheric Sciences. For this reason, the creation of a degree in this specialty at the Universidad Veracruzana was supported, which was created in 1976 and which, after an interruption, continues to be the only one in the country to date. Several students have finished their studies and have received their degrees, to later go on to strengthen the national meteorological services, and others have continued master's and doctoral studies, in Mexico and abroad, enriching research and teaching in the centres of Sciences of the Atmosphere and Ecology of the UNAM, as well as at the Universidad Veracruzana itself where, thanks to the strong support of the current university authorities, there has been an increase in teaching, research and dissemination activities, with a considerable increase in the number of students.

Creation of the Institute of Geophysics

I feel very moved when saying these words when the Institute of Geophysics has just turned fifty-four and the Centre for Atmospheric Sciences turned twenty-six, and it is not for nothing, since I have carried out my scientific research there since its foundation, and I dedicated most of my life to them as a researcher and as a director. I feel satisfied because I see that both institutions have borne many fruits and continue to do so.

To understand the foundation of the Institute of Geophysics, it is necessary to go back a few years, when the research and teaching infrastructure was developed at the University, especially in mathematics and physics, and the role that engineer Ricardo Monges López played in the said development. Once the infrastructure in mathematical and physical sciences was created, a logical step was to develop geophysics, in a country where there was already a tradition of Earth Sciences, where mining and oil have been powerful engines of geological and geophysical studies and where there are phenomena such as earthquakes, volcanic eruptions and hurricanes, droughts and floods.

The founder of the Institute was the engineer Ricardo Monges López, who died on 21 April 1983 at the age of 96 years and 6 months. His long life was fruitful and exemplary, standing out as a pioneer in the creation of the infrastructure of modern science in Mexico, especially mathematics, physics and geophysics. When the new University Statute was discussed in 1945, as director of the Faculty of Sciences, the engineer Monges López proposed the creation of the Institute of Geophysics. His proposal was approved, the Institute was included in Article 9 of the aforementioned Statute and, on 26 July 1946, the Rector commissioned him to present an organisation project for the new institute. On 8 October of that year, he was appointed director of the Institute of Geology, to develop the geophysical branches in it, before the new Institute began to function, and for that reason on that date he resigned from the direction of the Faculty.

During the time that he was director of the Institute of Geology, he dedicated himself to the study of the dynamics of the interior of the Earth by geological and geophysical methods and prepared the organisational project of the Institute of Geophysics.

He proposed and approved that the new Institute include the personnel and facilities of the National Seismological Service and the Teoloyucan Geomagnetic Station, which previously depended on the Institute of Geology.

Among the researchers of the nascent institute some very eminent ones were included, such as Manuel Sandoval Vallarta, Nabor Carrillo and Marcos Moshinsky, who shared their time as researchers with other university departments.

In March 1947, two years before the founding of the Institute, in order to begin preparing the personnel of the future Institute of Geophysics, the engineer Monges López invited Anselmo Chargoy and me to join the Institute of Geology, as research assistants, while still students of mathematics at the Faculty of Sciences. That invitation decided our future as researchers in the geophysical sciences and our admission to the Institute of Geophysics since its foundation.

At that time, I was preparing my civil engineering thesis under the direction of engineer Alberto J Flores, director of the National School of Engineers, on the development of a method to calculate the seismic effect on buildings. In order to obtain the seismic data I went to see the engineer Monges López. He was enthusiastic about my research and offered me the position of research assistant, with the initial task of finishing the thesis. On his side, Chargoy did his mathematical thesis on geomagnetism, under the direction of Dr Sandoval Vallarta.

Since March 1947, Chargoy and I met in the afternoons on the 4th floor of a building at Puente de Alvarado 71, to do our research. There were also several UNAM offices. As I recall, there was one from the Faculty of Sciences, another from the Scientific Research coordinator, Dr Nabor Carrillo, and a kind of UNAM job bank, run by Mr Horacio Labastida.

The programme presented for the operation of the Institute of Geophysics was approved by the university authorities and on 4 February 1949 it began to function under the direction of engineer Ricardo Monges López.

Once the Institute was inaugurated, the fundamental problem was to train researchers, without having a Geophysics school in Mexico, for which Monges López dedicated himself to choosing young people who were interested in geophysical sciences so that they could go to foreign universities to specialise, giving them all assistance and offering them appropriate jobs on their return.

From January 1951 to May 1953 I was doing my doctorate in applied mathematics in the United States at Brown University. Upon my return to Mexico, after the initial construction of the brand new Ciudad Universitaria had been completed, the Institute of Geophysics was established on floors 3, 4 and 5 of the then Tower of Sciences, and now Tower II of Humanities. Upon returning, the engineer Monges López invited me to help him with the academic-administrative task. However, I received his support to go abroad again in October 1954, this time to the International Institute of Meteorology, Stockholm University, Sweden, where I did studies in Atmospheric Sciences, and research under the direction of Professor Karl-Gustaf Rossby, a pioneer of modern meteorology.

Upon my return to Mexico, I had the privilege of collaborating with engineer Monges López as assistant director, a position I held for three years. By then, thanks to the creation of the Institute of Geophysics, Mexico was prepared to play a worthy role in the International Geophysical Year.

In October 1959, at the age of 73 and after 10 years at the head of the Institute, the engineer Monges López resigned and I was named titular director.

There was true continuity in the consolidation and growth of the Institute of Geophysics, periodic renewal of directors, growth and improvement of the academic level of researchers, as well as new equipment, buildings and facilities, up to the present time, with doctor Jaime Urrutia Fucugauchi as director.

We are very satisfied because, with the participation of the Institute, Mexico has joined the frontier level international of geophysical research, the Seismological Service has been improved and national geophysical problems are studied and solved, in coordination with other government and university agencies, having a scientific basis for it.

In addition, there is the Centre for Atmosphere Sciences, of which I was the founding director and which was created in February 1977 with personnel belonging to the Institute of Geophysics. Also, the now Institute of Marine Sciences and Limnology, when initially created as a centre, absorbed researchers and technicians in Physical Oceanography belonging to the Institute of Geophysics. In addition, the current Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), in Ensenada, began as an oceanographic project of the Institute of Geophysics, presented to CONACyT when I was director, which started operating in May of 1972 with Dr Nicolás Grijalva in charge.

Geophysical research has always been linked to teaching, and over several years the current teaching infrastructure has been created. The Faculty of Sciences, in its Physics major, includes a series of optional geophysics subjects, and the Faculty of Engineering also includes programmes that provide preparation in Earth Sciences, especially in applied aspects.

The UNAM offers studies in Earth Sciences at an advanced level, in which the Institutes of Geophysics, Geography and Geology, the Institute for Research in Applied Mathematics and Systems, and the Centre for Atmospheric Sciences participate, as well as the Faculty of Sciences and the Faculty of Engineering.

Master's degree and PhD studies are offered through these agencies within the framework of the Graduate Program in Earth Sciences, comprising more than 50 lines of research, under the direction of more than 120 tutors. In addition, the Institute of Marine Sciences and Limnology offers a doctorate that includes, among others, the specialty of Physical Oceanography.

Creation of the Centre for Atmospheric Sciences

Forty-nine years ago, upon returning to Mexico in May 1954, and after having completed my doctorate in Applied Mathematics at Brown University, Providence, Rhode Island, I found myself, like all who return, in a period of adaptation to reorganise my research within the Institute of Geophysics.

A few days later I met Dr C C Wallén, sent by UNESCO to advise our country on meteorological studies, and especially regarding the artificial stimulation of rain, which at that time seemed very promising and with immediate results. Doctor Wallén was installed in the Institute of Geophysics, in the Ciudad Universitaria.

I gave a series of three lectures at the Institute of Geophysics Seminar on the theme "Applications of the equations of the mechanics of continuous media in geophysics", and in one of the lectures the formulation of the equations of fluid dynamics and its possible application to the atmosphere. Doctor Wallén attended the lectures, without making any comment. However, the next day he picked me up from my cubicle and pointed out that studies like the ones I suggested were already being carried out by meteorologists, and that Professor C G Rossby, a pioneer in such studies, was then in Sweden at the International Institute of Meteorology at Stockholm University, and he asked me if I would be interested in spending time at the Institute. A few days later I received a personal invitation from Professor Rossby, and with the consent of engineer Ricardo Monges López I left for Sweden in October 1954 for a postdoctoral stay that would decide my entry into research in the area of atmospheric science.

It was the time when electronic computers were becoming available for research, which made it possible to try to solve fluid dynamics equations in a practical way, and the era of numerical models for climate prediction began, which was a magnificent opportunity for an applied mathematician. My ticket to Sweden was paid for by the Ministry of Foreign Affairs, at the request of the then coordinator of Scientific Research, Dr Alberto Barajas.

Upon returning to Mexico in May 1956, I began lines of research in atmospheric sciences at the Institute of Geophysics. The first was a continuation of the investigations carried out in Stockholm, referring to the causes of the trajectory of cyclones and which were published in Tellus in 1956. The other line of investigation was aimed at giving a physical explanation of the range of observed temperature in the atmosphere. The results of these latest investigations were presented at the XII Assembly of the International Geodetic and Geophysical Union, in Helsinki, in 1960, proving to be a new approach to study climate, and has served as a foundation for the development of the Thermodynamic Climate Model. In these investigations, the first computer installed at UNAM was used, by the founder of the Computer Centre, engineer Sergio Beltrán. José Luis Ottalengo Lara, in programming and computing, and Gustavo Camacho Gurza, in relation to solar radiation, cooperated with me in the initial investigation. The first article was also published in Tellus in 1962.

On the other hand, Dr C C Wallén, during his one-year stay, formed the Institute of Applied Sciences, where Pedro A Mosiño and Ernesto Jáuregui were initially hired. After Wallén, UNESCO sent Dr Edmund Fournier D'Albe, a specialist in cloud physics, who promoted the experiments to stimulate rainfall and the observations of solar radiation. During his four or five years of stay, Fournier D'Albe consolidated the Institute of Applied Sciences, which at that time occupied the third and fourth floors of the building where the Computer Services Centre and the Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas (IIMAS, the Applied Mathematics and Systems Research Institute) were located, in Ciudad Universitaria.

At the end of his mission, Fournier D'Albe was replaced by Dr Etienne Stretta, whose specialty was hydrology, promoting studies of groundwater hydrology. Ignacio Galindo, Armando Báez, Humberto Bravo, Rodolfo del Arenal and Jesús Martínez Guerrero also worked at the Institute of Applied Sciences.

In 1957, the staff of this Institute installed the Solar Radiation and Atmospheric Chemical stations in Altzomoni (on the slopes of Iztaccíhuatl), in Veracruz, and also in Chihuahua. Similarly, they founded the Central Solar Radiation Observatory in Ciudad Universitaria.

The influence of UNESCO specialists on the approach and solution of problems related to atmospheric circulation and aquatic resources were decisive.

In 1962, when the UNESCO mission withdrew, the staff of the Institute of Applied Sciences became part of UNAM. Thus, Mosiño, Báez, Bravo and Galindo joined Geophysics, and they started the Synoptic Meteorology, Atmospheric Chemistry, Pollution and Solar Radiation sections, respectively. In addition, Martínez Guerrero reinforced the Instrumentation area. On the other hand, Jáuregui joined Geography with his studies in Climatology and from Arenal to the Institute of Geology, with studies in Geohydrology.

From this moment on, a research group in Atmospheric Sciences began to consolidate at the Institute of Geophysics, with participation both nationally and internationally.

On 15 November 1961, the Mexican Geophysical Union and the International Geophysics journal were created. Of the 51 founding members, eleven were from the specialty of Atmospheric Sciences. I was appointed president.

In the period from 1971 to 1976, CONACyT gave high priority to atmospheric sciences, creating the National Indicative Meteorology Programme, which I presided over as executive member, and where the engineer Mosiño was Technical Secretary.

This programme oversaw the restructuring and modernisation of meteorological services, and a project was prepared that, unfortunately, was opposed by the military meteorological sector and was not implemented. This project is still valid and was presented again in 1988, as an urgent national need, without success. Said project can be updated once more to re-propose the modernisation of meteorological services.

In 1976 the research groups related to atmospheric sciences had reached a certain maturity in the Institute of Geophysics. The National Indicative Meteorology Programme in which they had actively participated was a great stimulus and the urgent need was felt to form a university unit dedicated to such studies. Thus, parallel to the project for the restructuring and modernisation of meteorological services, the project for the creation of an atmospheric research centre at UNAM was prepared. The idea of the new centre was well received by the then rector, Dr Guillermo Soberón, and the project was prepared in close collaboration with the coordinator of Scientific Research, Dr Agustín Ayala Castañares.

Being director of the Institute of Geophysics, I had to lead, and later present, the project before the Technical Council of Scientific Research for its discussion and approval, at the end of 1976.

The agreement for the creation of the Centre came out on 21 February 1977. It was integrated with the personnel who provided their services in the Departments of Atmospheric Sciences and Environmental Contamination, in the Laboratory of Atmospheric Chemistry and Water Contamination of the Institute of Geophysics, and in the Electronics and Atmospheric Mechanics workshops of the same.

At the beginning of its activities, the Centre was constituted with the research areas corresponding to the groups of researchers from the Institute of Geophysics, who changed their assignment to form part of the Centre.

The Centre was growing and improving its academic level, consolidating interdisciplinary research groups that carry out research on the following topics: the physical bases of climate and the development of models to explain and possibly predict its fluctuations, numerical models of short-term weather forecasting, synoptic meteorology, tropical cyclones, atmospheric electricity, cloud physics and urban weather, atmospheric chemistry, aerobiology, environmental pollution, environmental cytogenetics and mutagenesis, and radiation transfers. There is also an Instrumentation Laboratory, dedicated to the construction of instruments and to maintaining the existing equipment at the Centre.

The Centre for Atmospheric Sciences has reached a certain level that places it as the most important scientific research institution in the country in atmospheric sciences.

My main lines of research and contributions

1. Energy Balance Climate Models
The first Energy Balance model was published in 1962 in the Tellus journal. In the formulation of the model, an exchange coefficient (Austausch) similar to the one proposed by Defant in 1921 is used for the turbulent transport of thermal energy. Subsequently, the Saltzman models appeared in 1968, Sellers in 1969, Budyko in 1969 and others. At present there are numerous models of this type, which are of great importance for climate studies. This work served as the basis for developing the Thermodynamic Climate Model, which includes the Northern Hemisphere and a realistic distribution of continents and oceans.
2. Thermodynamic model for climate prediction
My best-known scientific contribution, and perhaps the most important, is the Thermodynamic Model for long-term weather forecasting. The investigations related to said model described in various articles establish that it represents a physico-mathematical basis, with great practical reality, for long-term prediction. These works are well-known and have been used in several countries, especially in the United States, Russia, Belgium, Japan, Germany, the Netherlands and Mexico.

The Thermodynamic Model is used for the prediction of temperature and precipitation anomalies for a period of one month for the entire Northern Hemisphere. The results of the model are verified based on observations, having obtained satisfactory results and continuing research to improve the results by incorporating new factors or refining existing ones.

At the Lamont Observatory at Columbia University, New York, many numerical prediction experiments have been carried out using this model since 1979. A verification over the territory of the United States has shown that the model has superior predictability to the traditional methods used at the American Weather Service. These results appeared in the Bulletin of the American Meteorological Society in 1986.

Dynamic-stochastic models based on the Thermodynamic Model, which have been recently developed by Russian scientists, are a new line of research of great importance for climate prediction.

In Mexico, of course, this model is also being adapted for the monthly and seasonal prediction of temperature and precipitation, and preliminary results have already been published. Collaborations with groups from the United States and Russia make it possible to complete the data banks and join efforts to improve predictions.
3. Numerical prediction of ocean temperatures
As a fundamental aspect of climate prediction, research has been carried out dealing with atmosphere-ocean interaction and ocean temperature prediction for the Northern Hemisphere.

This work is the first worldwide attempt to numerically predict ocean temperatures.

The results of 73 predictions published in Sweden in the international geophysical journal Tellus show that the method is successful and can be further improved by refining the incorporation of some of the factors.

Recent work has incorporated new oceanographic factors that improve predictions and, using a fine resolution grid (60 km), the annual cycle of surface temperature in the Gulf of Mexico has been simulated and experiments have begun for the prediction with higher resolution of monthly temperature anomalies in the same region.
4. Paleoclimatology and climate changes
The Thermodynamic Model is recognised worldwide as one of the main approaches to study the climate and its fluctuations. Its importance in relation to other models is described by Henderson-Sellers and K McGuffie (1990). The model has been a pioneer in the study of past climates: it was the first physical model to be applied to study the effect of the variation of the Earth's orbit on the climate (Milankovitch Theory). It was also the first to be applied to quantitatively verify that the drift of the continents produced the last terrestrial ice age (Shaw and Donn 1968, 1971, Donn and Shaw 1977).

I have applied the model, mainly, to study the evolution of the climate from the maximum glaciation of 18,000 years ago to the present, as well as the effect of ice caps, insolation anomalies and atmospheric carbon dioxide content in these climates. The temperatures that existed in that period, calculated by the model, are in agreement with the estimates based on analyses of fossil pollen and other periglacial evidence for the continent.

For the first time, the temperature anomalies that existed 18,000 years ago are calculated with a physical model, which are generally verified with the paleogeological estimates of CLIMAP (Climate: Long range Investigation, Mapping, and Prediction) (1981).
5. Effect of increased carbon dioxide on Earth's climate
The Thermodynamic Model of the climate has also been applied to estimate the effect of the increase in atmospheric carbon dioxide on the terrestrial climate. These works are actively continued and constitute an original approach, which is contributing significantly to understanding this effect. In paper presented in April 1991, at the annual meeting of the European Geophysical Society in Wiesbaden, Germany, the effect of the three feedback mechanisms (effect of water vapour, clouds and ice and snow) is analysed, demonstrating that the effect of water in the wavelength band from 12 to 19 microns in which the water and carbon dioxide combined, has a very important role, since the calculated increase in temperature due to an increase in carbon dioxide is tripled, when the effect of water in said band is not taken into account, which may explain the great variation that exists in the results obtained by various authors.
6. Studies on atmospheric vortices
These studies have served as a basis to explain the behaviour of atmospheric and oceanic vortices. The publication that appeared in the Tellus journal in 1956 is cited as the first correct physical explanation for the northwestward motion of tropical cyclones in the Northern Hemisphere. The pioneering nature of this publication is mentioned by R A Anthes (1982) in his classic monograph on tropical cyclones, as well as in several articles, some very recent, on the movement of both atmospheric and oceanic vortices. New studies have fully corroborated my results, obtained in 1956.
7. Propagation of waves in circular elastic rods
In the article written by Miklowitz on the progress of the investigation of the propagation of elastic waves, which appeared in Vol. 13, No. 12, December 1960, of the Applied Mechanics Review, this work is cited as one of the most important of those published in recent years on the propagation of elastic waves in circular bars, since it demonstrates, for the first time, that the fundamental equation that governs these phenomena has complex roots, the importance of which grows at the extremes of the bars and whose number is infinite for compression waves.
Other investigations
Complete information about my research and references appears in the publications of my Works and my Biobibliography of El Colegio Nacional.

Various investigations have been carried out in various parts of the world, some of which have already been cited; in this regard, and to conclude, I will mention some of them.
As I already said, the initial work of the Model was developed in Mexico and presented in Helsinki at the meeting of the International Geodetic and Geophysical Union in 1960, and was very favourably accepted by eminent meteorologists such as Fjfrtoft, from Norway, Bergeron, from Sweden, and others, who congratulated me. In addition, the day after the presentation of the work, Professor Walter Hansen, director of the Oceanographic Institute of the University of Hamburg, Germany, had breakfast with me, and invited me to spend a season as a visiting professor to teach the course "Hydrodynamics of the oceans." Upon returning to Mexico, I informed Dr Ignacio González Guzmán, coordinator of Scientific Research, of the invitation, who told me that said invitation was exceptionally honourable and supported me in obtaining authorisation for the trip. During my stay at the University of Hamburg, in addition to teaching said course, I did research to extend the climate model, including equations for the oceans and continents, coupled to the equation for the atmosphere, having the benefit of discussions with Professor Hansen and other colleagues from the University of Hamburg.

At the end of my course, Hansen offered me a longer stay as a teacher, which was a wonderful offer. However, my loyalty was with Mexico, where I was expected to continue as director of the Institute of Geophysics, as well as a researcher at the same Institute and professor at the Faculty of Sciences. In my absence, Master Chargoy had remained in charge of the direction. I returned to Mexico in April 1962.

In the summer of 1962, Dr Jerome Namias was a visiting professor at the Institute of Geophysics and I took the opportunity to discuss with him the results that I had obtained so far with the model and that had already been published in Tellus. His opinion was very favourable, and he told me that he saw great potential in the work for long-range weather forecasting and immediately invited me to spend a season at the National Weather Centre (NMC), where he was head of the group that carried out monthly and seasonal forecasts.

Once again I consulted with Dr Ignacio González Guzmán, and obtained permission to spend a sabbatical year at the National Meteorology Centre, from October 1962 to November 1963.

I had well defined my main research objective, which was to use the model developed with the small computer that was then at UNAM, to create a hemispheric model for monthly and seasonal prediction, with a realistic distribution of continents and oceans. The enormous task of preparing the data involved several meteorologists and computer experts, and I always had the enthusiastic support of Philip F Clapp and Jerome Namias.

To carry out the predictions, the data used subjectively to make the forecasts were incorporated into the model, which were the anomalies of the temperature of the oceans and of the ice and snow cover in the month prior to the month of the prediction.

Experiments began with the January 1963 forecast, and the results, published in the Monthly Weather Review, were successful in correctly forecasting large temperature anomalies, especially over the United States, where there was a very cold January.

Encouraged by the results, the experiments were continued and published in magazines with global circulation.

Upon returning to Mexico, I continued as a project consultant, making short stays authorised by the Technical Council.

In October 1965 I finished my first term as director and I asked the Rector not to propose me for a second term, in order to dedicate myself completely to scientific research and to refine the Model. The next five years were spent as a full-time researcher at the National Meteorology Center. After five years as a researcher at that centre in Washington, D.C., Dr Pablo González Casanova, then rector of UNAM, called me on the phone to inform me that several researchers were proposing me as a candidate for a second term as director of the Institute of Geophysics. After consulting with the family, I accepted the proposal and moved to Mexico, following the recommendations of the rector. The Governing Board unanimously appointed me director and I rejoined the UNAM, with my old position as top-ranking researcher.

As the University already had a computer where the Thermodynamic Model could be run, experiments were started specifically aimed at monthly and seasonal prediction in the Mexican Republic. On the other hand, the original Washington project continued to count on me as a consultant.

Several institutions in different countries have been interested in doing numerical experiments with the Model, especially the Lamont Observatory at Columbia University, in New York, where, as I already said, many numerical experiments were done to improve predictions of the Model; the Max-Planck Institute for Meteorology in Hamburg, Germany, where I spent a sabbatical year and where I adapted the Model to simulate past and future climates; the Catholic University of Louvain, in Belgium, where for several years I was invited as a visiting professor for periods of one month; and where in collaboration with Professor André Berger and other researchers I carried out research on climates of the past; the former Soviet Union and present-day Russia, where numerous applications described in a note published by Dobrovolski in the journal Atmósfera have been and continue to be made.

In Mexico there is a group at the Centre for Atmospheric Sciences that is dedicated to improving the Model, especially in relation to precipitation prediction, as well as applications to monthly and seasonal weather forecasting in the Mexican Republic; the effect of carbon dioxide on global warming; the simulation of past and future climates, the climatic effect of changes in solar radiation, the prediction of oceanic temperature anomalies in the Northern Hemisphere, and their effect on climate, including the "El Niño" phenomenon.

For all that has been said, we will always remember with gratitude all those who, with their valuable participation, made it possible to reach the new millennium with a well-consolidated infrastructure in geophysical sciences with the creation of the Institute of Geophysics, the Centre for Atmosphere Sciences and the Institute of Marine Sciences and Limnology, which were created in the 1950s in the Ciudad Universitaria. CICESE was also created in Ensenada, and the Degree in Atmospheric Sciences at the Universidad Veracruzana.

We also had the satisfaction of creating the Mexican Geophysical Union and the internationally renowned journals Geofísica Internacional and Atmósfera, sponsored by UNAM. In conclusion, a solid infrastructure has been created in these specialties of science to be able to grant master's degrees and doctorates of a high academic level, and carry out research of excellence, which has already placed Mexico on a global level at the level of the countries more developed in science.

Thank you.

Last Updated June 2023