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trabalho completo - 52ª Reunião Anual da Sociedade Brasileira de
52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Influência do aquecimento global sobre as variáveis climatológicas e índice de conforto térmico no
estado da Paraíba
Bonifácio Benício de Souza1, Gustavo de Assis Silva2, Elisângela Maria Nunes da Silva3
1
Zootecnista, Professor Associado - UAMV/CSTR/UFCG – Campus de Patos-PB. E-mail: [email protected]
2
Aluno do Programa de Pós-graduação em Medicina Veterinária – UFCG, Patos, Paraíba. Extensionista rural do IPA.
3
Pós-Doutoranda em Medicina Veterinária – UFCG, Patos, Paraíba. Bolsista CNPq
Resumo: O objetivo deste trabalho foi avaliar o efeito do aquecimento global sobre as variáveis
climatológicas e índice de conforto térmico no estado da Paraíba. Foram coletadas os dados climatológicos e
calculados o índice de temperatura e umidade em quatro estações meteorológicas distribuídas por todo
estado no período das normais de 1961-1990 e nos últimos quatro anos 2011-2015. Houve aumento em todas
as regiões do estado para a temperatura ambiente e o ITU. Concluiu-se que todas as regiões do estado da
Paraíba estão sofrendo alterações climáticas em decorrência do efeito estufa e que o estresse térmico
demonstrado pelo ITU, indica que mudanças de atitudes deverão ser intensificadas para possibilitar a
sobrevivência e melhorar a produção animal em todo estado.
Palavras-chave: temperatura, clima, efeito estufa, Paraíba
Global warming influence on the weather and thermal comfort index in the state of Paraiba
Abstract: The objective of this study was to evaluate the effect of global warming on the weather and
thermal comfort index in the state of Paraíba. Climatological data were collected and calculated the
temperature humidity index in four weather stations distributed throughout the state in the period of the
normal 1961-1990 and the last four years from 2011 to 2015. There was an increase in all regions of the state
to room temperature and the THI. It was concluded that all of Paraíba state regions are suffering from
climate change due to the greenhouse effect and the heat stress demonstrated by the ITU indicates that
attitude changes should be intensified to enable the survival and improve animal production in every state.
Keywords: temperature, climate, greenhouse effect, Paraíba
Introduction
In recent decades the world has experienced many disasters resulting from rapid climate change with
devastating effects. The increase in the concentration of greenhouse gases originated from burning fossil
fuels has been identified as the main cause of global climate change resulting from the greenhouse effect in
the Earth's atmosphere. According to the consolidated climate projections in the fourth assessment report of
the Intergovernmental Panel on Climate Change (IPCC), the global mean air temperature must continually
increase over the twenty-first century (Meehl et al. 2007).
According to Lucena (2010) global climate change can generate impacts on natural and human
systems, making it necessary to investigate potential vulnerabilities and adaptation options.
Among the climatic variables that most influence the lives of warm-blooded animals to room
temperature and relative humidity are the ones that stand out, since together, these variables directly affect
the evaporative heat loss, affecting thermoregulation and thus, the performance and animal production.
Therefore, the aim with this study was to evaluate the effect of global warming on the weather and
thermal comfort index in the state of Paraiba, Brazil semi-arid.
Materials and Methods
The study was conducted in the state of Paraiba, from the get meteorological data from the database
for research and education (BDMEP, INMET) four weather stations distributed by the state, located in the
following cities and regions: Campina Grande (Agreste) João Pessoa (Litoral), Monteiro (Cariri) and Sao
Goncalo (High Hinterland). Environmental variables dry bulb temperature (DBT), relative humidity (RH),
rainfall (PP) were studied in the periods (1961-1990) and (2011-2015) and the temperature humidity index
(THI) It was calculated using the equation proposed by Thom (1959), as described below. THI = dbt + 0,36
tpo + 0,42 onde: dbt = dry bulb temperature ºC e dpt= dew point temperature ºC. The means were analyzed
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
from the difference between the normal period of 30 years (1961-1990) and the period of the last four years
(2011-2015). The values obtained allowed to determine climate changes that occurred in Paraíba due to
global warming by the action of greenhouse gases.
Results and Discussion
Based on the data we found a significant increase of room temperature in every region of the state of
Paraiba, which was shown by the difference between the averages of the period of the normal 30 years
(1961-1990) and the averages of the last four years (2011 - 2015), table 1. The highest temperature rise was
observed in the weather station of the city of Monteiro, Paraíba Cariri and the smallest increase was
observed in the coastal region.
Table 1. Climate variables, ambient temperature and relative humidity, the Paraíba state in the period of
normal (1961-1990) and the last four years (2011-2015).
Municípalities of
Paraíba
Temperature (°C)
196120111990
2015
Campina Grande
João Pessoa
Monteiro
São Gonçalo
22,40
26,10
23,69
26,50
24,34
27,66
26,00
28,65
∆T (°C)
1,94
1,56
2,31
2,15
UR (%)
1961-1990
20112015
74,70
80,80
62,70
59,80
76,57
74,5
60,74
63,28
∆UR (%)
1,84
- 6,3
- 1,96
3,48
These results agree to preliminary data released by the IPCC (Intergovernmental Panel on Climate
Change) in September 2013. According to the IPCC the Brazilian climate could suffer the effects of global
warming by the end of this century. The South and Southeast regions may have increased to 0.5% in average
temperature by the end of the century and the Midwest, Northeast and North may have average temperatures
increased by 1.5%. As for IPCC these optimistic projections, that is, controlling the emission of greenhouse
gases. In contrast scenario, the temperature may rise more than the double compared to these projections.
As a consequence of such heating would be: melting glaciers, the elevation of the oceans due to the
melting and thermal expansion of the water, increasing the amount of clouds, water vapor, and consequently,
the amount of rainfall, change in environment characteristics in different regions of the planet (Xavier &
Kerr, 2004).
The relative humidity showed greater mean decrease on the coast (João Pessoa) and higher in the
high backcountry (São Gonçalo). The effects of moisture on the climate are felt both in temperature and in
rainfall. Water, because of its specific heat, tends to keep longer temperatures, so that there is a smaller
variation of them, namely the amplitude is smaller the higher the humidity. In addition, in more humid
regions or who are most affected by humidity, rainfall tends to be higher, because the saturation of the air
causes condensation is more frequent.
High ambient temperatures associated with high relative humidity are the main factors that interfere
negatively on productivity. Since these variables together difficult when the heat loss by evaporative forms,
breath and perspiration. What depending on the species may become a limiting factor of animal exploitation
for economic purposes in certain regions.
Table 2 shows the mean and the differences between the averages of precipitation and temperature
and humidity index (THI) in the state of Paraíba.
Regarding rainfall there was a reduction in the amount of rainfall for three regions in recent years
compared to the normal of the period (1961-1990), represented by the municipalities of João Pessoa,
Monteiro and São Gonçalo, coastal, cariri and the high wilderness regions, respectively.
Regarding the THI it was observed that there was an increase above 2 points for all regions, with the
highest average observed in São Gonçalo 3.52 from above hinterland region. These results demonstrate that
the condition of thermal comfort for the livestock in all of Paraíba state regions is becoming more difficult to
achieve. For Azevedo et al. (2005) THI is an excellent indicator of thermal comfort, since this index takes
into account the relationship between the ambient temperature and relative humidity.
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Table 2. Means of rainfall and temperature humidity index the difference between these variables in relation to the
normal period (1961-1990) and the last four years (2011-2015) in the state of Paraíba.
Municípalities of
Paraíba
Campina Grande
João Pessoa
Monteiro
São Gonçalo
Precipitation (mm)
61-90
11-15
875,4
893,47
2145,4
1941,35
712,5
555,6
995,5
860,97
THI
∆P
18,7
-204,05
-157
-134
61-90
70,58
75,18
71,95
74,32
∆THI
11-15
73,00
77,94
74,21
77,84
2,42
2,76
2,26
3,52
According to Rosenberg et al. (1983) an THI between 75 and 78 is an alert condition to producers,
indicating that action must be taken to avoid losses, which was observed in this study for the municipalities
of João Pessoa, 77.94 and São Gonçalo, 77, 84, litoral and high wilderness regions, respectively. Yet
according to the authors measures of a THI 79-83 means danger, especially for feedlot cattle and THI equal
to or greater than 84 is an emergency situation, emergency measures must be taken to avoid loss of animals.
Conclusions
All Paraíba state regions are suffering from climate change due to the greenhouse effect. The average
elevation of THI in recent years indicates that changes in attitude should be intensified to allow the survival
and productivity of farm animals do not become increasingly expensive in the state.
Acknowledgements
The INMET for providing data from meteorological database for teaching and research of weather
stations located throughout the state of Paraíba.
Literature Cited
AZEVEDO, M.; PIRES, M.F.A.; SATURNINO, H.M. et al. 2005. Estimativa de níveis críticos superiores
do índice de temperatura e umidade para vacas leiteiras 1/2, 3/4 e 7/8 Holandês-Zebu em lactação.
Revista.Brasileira de Zootecnia34: 2000-2008.
ROSENBERG, N.J; BLAD, B.L; VERMA, S.B. 1983. Microclimate: the biological environment. 2ed. New
York: Wiley-interscience Publication.
LUCENA, A.F.O. 2010. Proposta metodológica para avaliação da vulnerabilidade às mudanças climáticas
globais no setor hidroelétrico. Tese Doutorado. Universidade Federal do Rio de Janeiro, Rio de Janeiro.
MEEHL, G.A., T.F. STOCKER, W.D. COLLINS, P. FRIEDLINGSTEIN, A.T. GAYE, J.M. GREGORY,
A. KITOH, R. KNUTTI, J.M. MURPHY, A. NODA, S.C.B. RAPER, I.G. WATTERSON, A.J. WEAVER,
Z.-C. ZHAO, 2007, “Global Climate Projections”. Climate Change 2007: The Physical Science Basis.
Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on
Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L.
Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
THOM, E.C. 1959. The discomfort index. Weatherwise, Boston, 12:57-60.
XAVIER, M.E.R.; KERR, A.S. 2004. A análise do efeito estufa em textos paradidáticos e periódicos
jornalísticos. Cad. Bras. Ens. Fís., 21:325-349.
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