Editorial

Climate Changes

Multiciencia Journal -
Number 8
May 2007
ISSN: 1806-2946

Jurandir Zullo Junior
CEPAGRI/UNICAMP

Two thousand and seven will be known in History as the year when the theme of climate change and its impacts ceased to be a subject mostly limited to the academic area and became part of the everyday life of people and of the discussion agendas of national and international development policies. This great interest in the subject may be explained by the following major reasons:

•  The publication of IPCC's fourth assessment report (Intergovernmental Panel on Climate Change) during the year, with an increase in the possibility of changes, of anthropogenic origin, in the Earth's climate in the next decades, when compared to what was presented in the third report;

•  Wide media coverage of IPCC's fourth report disclosure and to the theme in general, with presentation of several special programs on climate change and its impacts;

•  A common feeling, increasingly expressed by people, that the climate has been showing a different behavior from that which was observed a few years ago in various locations of the Earth;

•  Considerable repercussion of “An Inconvenient Truth”, a film by the former vice-president of the United States , Al Gore, in 2006;

•  Great present dependency of human activities on the weather and climate conditions.

•  Increase in number and intensity of extreme meteorological and climatic phenomena and the damages related to them, such as the heat wave in Europe in 2005, hurricanes Katrina and Wilma in the Northern Hemisphere, hurricane Catarina on the Southern Coast of Brazil, and the flooding in the larger Brazilian cities;

•  Great vulnerability of the cities to adverse climatic and meteorological conditions, where more than half of the world's population lives.

The current relevance of the theme of climate change was emphasized by the Nobel Prize granted to IPCC and to the former North-American vice-president, Al Gore, at the end of 2007. This increase in the importance of the theme of climate change and its impacts on society brought a number of challenges to the scientific community working in this area:

•  To publicize existing knowledge in language suitable for each one of the various segments of interested public, seeking to increase the general knowledge of the subject;

•  To detect concrete occurrences of change in the Earth's climate, differentiating them from the perfectly normal alterations and variations, especially in tropical regions;

•  To propose mitigating solutions that will postpone and/or decrease the alterations of anthropogenic origin on the Earth's climate in the next decades;

•  To develop adapting solutions to minimize the impacts of an adverse climate situation on the main human activities on Earth.

One remarkable characteristic of these four items is that they are highly interdisciplinary, embracing several areas of human knowledge such as atmospheric science, mathematical modeling, economics, energy, biology, agriculture, health, transportation, and demography, among others. Besides the challenges that confront the scientific community, it is important to emphasize the challenge presented to society by the possible undesirable impacts of climate changes: to adopt measures that will not only directly benefit the present generation, but will be vital to future generations. This involves a change in people's day-to-day behavior and, most of all, of the actions of public administrators who will plan and make long term decisions - something uncommon in many societies and of great difficulty to politicians who are continuously concerned about their next election.

It is based on these great challenges that climate change and its impacts bring to present day society and to the scientific community in general, that this issue of Multiciência Journal was organized. The interdisciplinary character of the subject was another impelling aspect for this edition, since it is a publication produced by the system of Centros e Núcleos Interdisciplinares de Pesquisa da Unicamp ( Unicamp Interdisciplinary Centers and Research Nuclei). The journal was organized with a feature article by MARENGO and VALVERDE giving a general overview of the subject, and then articles dealing specifically with energy, (WALTER), health (CONFALONIERI and MARINHO), demography (CARMO), biodiversity (BUCKERIDGE) and agriculture (SEGUIN, BAETHGEN, PELLEGRINO et al.). Two reviews are also presented: one on the fourth report of the IPCC (ÄVILA), and the other one on the film “An Inconvenient Truth” (COTTA WALTER). The larger emphasis on agriculture, with three articles, is due first of all to the importance of this sector to the country.

Furthermore, while Brazilian agriculture appears to be highly susceptible to climatic changes currently predicted, as published in a few scientific journals, it also has great potential to adapt to different climate conditions. This could be of great use in the development of mitigating measures to climate change, such as those related to the use of biocombustibles.

In the general overview article, MARENGO and VALVERDE present the state of the art in studies of climate tendencies for Brazil developed over the last 50 years. They also analyze scenarios for climate in the future (that is, until 2100) generated by the models used in the fourth IPCC report, called AR4, on both a national scale and a regional scale (Northeast, Amazon, and Bacia do Prata). The projections of AR4 until 2100 are discussed in relation to scenarios presented in earlier studies using models produced in the third IPCC report, published in 2001. The analysis and discussions pertain to rainfall and river flows.

In the article that deals with the energy sector, WALTER points out that the different steps in the energy supply chain contribute a significant portion (between 60% and 65%) of the emission of greenhouse gases. This tendency should be maintained, in spite of efforts to use energy efficiently and the development of renewable energy sources. The biggest challenge of the energy sector is to reduce significantly the emission of greenhouse gases associated with the use of energy without sacrificing the standard of living of the world's population.

As it relates to the main implications that climate changes have on human health, CONFALONIERI and MARINHO treat the issue based on historical knowledge of the relationship between climate variations and health in Brazil , recent research on the spatial distribution of the vulnerability in the Brazilian geographical space, and the application of general data produced by IPCC. The possible effects of global environmental changes, due to climate changes, on certain aspects of demographic dynamics are discussed in the article by CARMO. One of the aspects emphasized in this article is that if the global environmental changes are produced in a short period of time, they can exacerbate the social vulnerability of the social groups in worst economic conditions due to the increase of existing risk factors.

BUCKERIDGE uses a chain theory to discuss some of the main effects of global climate change on biodiversity. A hypothesis is raised in which the variations over a certain level in atmospheric concentrations of CO 2 , in the temperature and in water availability for photosynthetic organisms make the biosphere network system capable of drastically altering its balance, producing something unique, and thus changing to a new state. It is suggested that the knowledge and technology needed to find new paths that will avoid global unbalance already exist, but that it will require a huge intellectual effort and will probably include the network theory as a strategic tool.

Three articles are presented in the agricultural segment. SEGUIN discusses the impact of climate changes on European agriculture in an evolving context which includes the Common Agricultural Policy (CAP) and its corresponding subsidies, concerns with environmental protection, concerns with consumer health, the use of biomass as a renewable energy source, and the reduction in the use of fossil energy. BAETHGEN in turn discusses the mitigation, adaptation, and decision making associated with climate change in agriculture, focusing especially on developing countries. Several challenges associated to this were pointed out, such as: implementation of projects geared to the carbon market for small farmers in developing countries and making the spatial scales of the climate scenarios (global and regional) compatible with the scales necessary for decision makers (local). PELLEGRINO et al. analyse the current context of the interactions between global climate change and agriculture in Brazil . The contributions of agriculture to the intensification of the greenhouse effect and climate change are discussed, as well as the impact of climate change on Brazilian agriculture, focusing on the definition of future agricultural scenarios based on mathematical models which represent the processes involved in productive systems. Several aspects of the problem are presented as well as ways of approaching them in a multidisciplinary research network.

The main fields of knowledge pertaining to the development of the climate change theme and its impacts were therefore analyzed in this edition of Revista Multiciência. In this manner we hope to contribute significantly to the various discussions that are underway in Brazil and in the world as it relates to the future of planet Earth and the human species.