|Dr. Tatsushi Tokioka
Program Director, Global Warming Research
Frontier Research System for Global Change
|Dr. Tokioka joined us in this April
as a full-time program director, after Dr. Shukuro Manabe's return
to the United Sates in November 2001, to lead a team of 19 researchers.
What is the current work of your team?
|Tokioka : We see our current challenge
to reduce uncertainties in global warming projection, which means
narrowing the range of the predicted values that project global temperatures
to rise between 1.4ºC to 5.8ºC by the year 2100*. To meet
this challenge, we must identify first the advantages of the current
climate models and next the factors that cause uncertainty. We objectively
evaluate and analyze the models as a Global Warming Research Program
team. As a part of our efforts, we use current models to simulate
characteristic climate conditions in the past, such as during the
Ice Age, to test the models. Moreover, we have developed a biogeochemical
oceanic general circulation model to serve as the ocean that affects
atmospheric CO2 concentration significantly.
This model includes not only physical and chemical processes but also
marine ecosystems. Meanwhile, by utilizing the Earth Simulator, which
started operation in March 2002 on the campus of the Japan Marine
Science and Technology Center, Yokohama Institute for Earth Sciences,
we are going to increase the model's resolution to achieve more accurate
We continue to follow Dr. Manabe's research organization focused on
the three themes of global warming, paleoclimate, and carbon cycle.
We strive to establish a research environment where each researcher
can fully utilize his or her talents and specialties to produce good
|What encouraged you to join the field
|Tokioka : While I was in junior high
school, I became interested in the study of weather in science class.
I used to listen to weather reports on the radio every day starting
from 4 p.m. and I drew weather maps. By drawing pressure contours,
I identified such features as the location of low-pressure areas and
the position of fronts. When I compared the maps of consecutive days,
I could see the movement of low-pressure areas. Then I wondered why
low pressures moved from west to east. Having just learned about the
rotation of the Earth in science class, I was thinking that low pressures
should move from east to west, opposite to the movement of the Earth's
surface. Later, when I entered university, I realized that this question
was a key to understanding atmospheric general circulation. I guess
that my strong interest and curiosity in science during my junior
high school years led me to study Earth systems.
| In 1990, while you were engaged
in research at the Japan Meteorological Agency, how did you get involved
in the IPCC First Assessment Report?
|Tokioka : The condition of the Earth's
atmosphere is determined by the interaction of land, oceans, cryosphere
and biosphere. However, until the 1970s, mainstream research dealt
only with the atmospheric part. In the latter half of the 1980s, the
Meteorological Research Institute of the Japan Meteorological Agency
began developing models that incorporated the major parts of the climate
system. Meanwhile, there was increasing momentum among scientists
participating in the World Meteorological Organization (WMO) and the
United Nations Environmental Program (UNEP) to send messages to policy
makers in each country regarding the issue of the rising CO2
concentration in the atmosphere and global warming. IPCC was then
founded in 1988. So we started an experiment with a model that combined
the atmospheric general circulation model and the mixed-layer ocean
model to study equilibrium climate change due to the doubling of atmospheric
CO2. Dr. Manabe, the previous full-time
program director, had already done a similar experiment 20 years before.
Therefore, we placed our emphasis of study on changes in precipitation
characteristics at the level of doubled CO2.
I felt that changes in the hydrological cycle due to global warming
were important from the viewpoint of the Earth's ecosystems and disaster
prevention in our society. Our study on changes in precipitation characteristics
under global warming was well received by the IPCC. So I was appointed
as one of the lead authors for the IPCC First Assessment Report published
in 1990. At the Meteorological Research Institute, we began new research
on climate changes due to the gradual increase of atmospheric CO2
concentration, using a model where a mixed-layer ocean model is replaced
by an oceanic general circulation model. We presented our results
to the IPCC Second Assessment Report published in 1996.
| What are some key points when conducting
research related to global warming prediction and climate change mechanisms?
|Tokioka : First, we would
like to contribute to policy decisions by providing reliable information
about global warming projection. Beyond that, we are also engaged
in research and experiments to provide useful information for decision
making, such as characteristic changes of typhoons, summer and winter
monsoons, and extreme events over 100 years, which would significantly
influence our lives. Considerable uncertainties exist in these changes.
Therefore, we believe it is very important for us to understand these
global change mechanisms to protect both our society and the natural
ecosystem. We especially emphasize the importance of analysis of various
output data to accurately understand them.
| As the Director of the Global Warming
Research Program, what are your efforts in relation to the IPCC Fourth
|Tokioka : First, within this year, we
plan to determine a climate model to be used to produce results, so
that we can submit them to the next IPCC Assessment Report. Specifically,
we are planning to conduct experiments with a high-resolution climate
model, following several scenarios of atmospheric composition change
in a time frame of 100 to 200 years. The Fourth Assessment Report
is scheduled to be adopted in 2007. Although time is limited, we will
try to do our best to present our results by enhancing research activities
in the Global Warming Research Program. We will continue our studies
on processes relevant to global warming, carbon cycle modeling, and
paleo-climate. We will work not only with other FRSGC Programs, but
also with other research groups, such as the Center for Climate System
Research, University of Tokyo, the National Institute for Environmental
Studies, and the Meteorological Research Institute.
Thank you very much.
*Prediction value presented by the IPCC in the Third Assessment Report
|By developing more accurate
climate models and analyzing model outputs of global warming
experiments, I would like to contribute to policy making that
will lead to protection of the global environment.
After joining the Japan Meteorological Agency in 1971,
Dr. Tokioka worked as a researcher on atmospheric general
circulation and climate. For two years from 1974, he worked
at the University of California at Los Angeles (UCLA)
for Dr. Akio Arakawa, one of the pioneers in the development
of atmospheric general circulation models. After serving
as a Head of the Office of Climate Programs in 1994, and
as the director-general of the Sendai District Meteorological
Observatory in 2001, Dr. Tokioka served as the president
of the Meteorological College until April 1, 2003. He
specializes in climate modelings and atmospheric general
circulations, and he has dealt with a variety of climate
Characteristics of the IPCC Fourth Assessment
Report and the Involvement of the FRSGC.
- The IPCC Fourth Assessment Report is scheduled to be adopted
in 2007, and along with the Third Assessment Report published
in 2001, it will serve as an important basis for international
framework negotiations for the second commitment period (goal
for reducing greenhouse gases by 2013-2017).
- The IPCC evaluates the content of research papers presented
by research organizations in other countries regarding the prediction
of climate changes related to greenhouse gases, and countermeasures
for the impact on nature and the economy, and compiles these papers
as the IPCC Assessment Report.
- Main points of the Fourth Assessment Report
Concepts such as climate models (simulation of climate values
and seasonal changes), paleoclimate, causes for climate variations
and changes, and predictions utilizing climate models, have been
listed by the sub-committee. Following the examination of these
main points, they are to be approved along with a publication
plan at the 21st IPCC Conference to be held in November 2003.
- Schedule of the main events for developing the Fourth Assessment
November 3-7, 2003: 21st IPCC Conference (discussion and approval
of main points and plan for publication)
November 2003: IPCC secretariat accepts applications for authors
and proofreaders from research organizations and other countries.
April 2004: IPCC and sub-committee bureau select authors and proofreaders.
June 2004 and thereafter: First meeting for lead authors (CLA/LA)
To actively contribute to this process, the FRSGC has been conducting
research on climate change prediction to be presented as research
papers in all programs. Moreover, last year, the Ministry of Education,
Culture, Sports, Science and Technology began its Project for the
Sustainable Coexistence of Humans, Nature, and the Earth, which
was designed to develop models for global warming and hydrologic
cycles. The FRSGC participates in this project, and is developing
integrated models that can simulate global changes that result from
the interaction of climate, atmospheric conditions, marine composition,
and land and marine ecosystems, as well as in highly precise global
warming predictions, including feedback for the carbon cycle using