Monitoring canopy and air temperature of dominant vegetation in tropical semi-arid using bioclimatic model

Typical vegetation of arid environments consists of few dominant species highly threatened by climate change. Jurema preta (Mimosa tenuiflora (Willd.) Poiret) is one of these successful species that now is dominant in extensive semiarid areas in the world. The development of a simple bioclimatic model using climate change scenarios based on optimistic and pessimistic predictions of the Intergovernmental Panel on Climate Change (IPCC) shown as a simple tool to predict possible responses of dominant species under dry land conditions and low functional biodiversity. The simple bioclimatic model proved satisfactory in creating climate change scenarios and impacts on the canopy temperature of Jurema preta in semiarid Brazil. The bioclimatic model was efficient to obtain spatially relevant estimations of air temperature from determinations of the surface temperature using satellite images. The model determined that the average difference of 5oC between the air temperature and the leaf temperature for Jurema preta, and an increase of 3oC in air temperature, promote an increase of 2oC in leaf temperature. It leads to disturbances in vital physiological mechanisms in the leaf, mainly the photosynthesis and efficient use of water.

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Hydrologic sensitivity of the Upper San Joaquin River Watershed in California to climate change scenarios

Hydrology Research ◽

10.2166/nh.2012.441 ◽

2012 ◽

Vol 44 (4) ◽

pp. 723-736 ◽

Cited By ~ 10

Author(s):

Zili He ◽

Zhi Wang ◽

C. John Suen ◽

Xiaoyi Ma

Keyword(s):

Climate Change ◽

Sierra Nevada ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Hydrological Simulation ◽

River Watershed ◽

System Sensitivity ◽

Hspf Model ◽

San Joaquin River ◽

San Joaquin River Watershed

To examine the hydrological system sensitivity of the southern Sierra Nevada Mountains of California to climate change scenarios (CCS), five headwater basins in the snow-dominated Upper San Joaquin River Watershed (USJRW) were selected for hydrologic simulations using the Hydrological Simulation Program-Fortran (HSPF) model. A pre-specified set of CCS as projected by the Intergovernmental Panel on Climate Change (IPCC) were adopted as inputs for the hydrologic analysis. These scenarios include temperature increases between 1.5 and 4.5 °C and precipitation variation between 80 and 120% of the baseline conditions. The HSPF model was calibrated and validated with measured historical data. It was then used to simulate the hydrologic responses of the watershed to the projected CCS. Results indicate that the streamflow of USJRW is sensitive to the projected climate change. The total volume of annual streamflow would vary between −41 and +16% compared to the baseline years (1970–1990). Even if the precipitation remains unchanged, the total annual flow would still decrease by 8–23% due to temperature increases. A larger portion of the streamflow would occur earlier in the water year by 15–46 days due to the temperature increases, causing higher seasonal variability of streamflow.

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Historical and future temporal trends in the summer Urban Heat Island of Athens (Greece)

10.5194/ems2021-318 ◽

2021 ◽

Author(s):

Tim van der Schriek ◽

Konstantinos V. Varotsos ◽

Dimitra Founda ◽

Christos Giannakopoulos

Keyword(s):

Climate Change ◽

Air Pollution ◽

Air Temperature ◽

Temporal Trends ◽

Temperature Data ◽

Climate Change Scenarios ◽

Heat Island ◽

Hot Days ◽

The Future ◽

Urban Heat

Historical changes, spanning 1971&#8211;2016, in the Athens Urban Heat Island (UHI) over summer were assessed by contrasting two air temperature records from established meteorological stations in urban and rural settings. When contrasting two 20-year historical periods (1976&#8211;1995 and 1996&#8211;2015), there is a significant difference in summer UHI regimes. The stronger UHI-intensity of the second period (1996&#8211;2015) is likely linked to increased pollution and heat input. Observations suggest that the Athens summer UHI characteristics even fluctuate on multi-annual basis. Specifically, the reduction in air pollution during the Greek Economic Recession (2008-2016) probable subtly changed the UHI regime, through lowering the frequencies of extremely hot days (Tmax > 37 &#176;C) and nights (Tmin > 26 &#176;C).Subsequently, we examined the future temporal trends of two different UHIs in Athens (Greece) under three climate change scenarios. A five-member regional climate model (RCM) sub-ensemble from EURO-CORDEX with a horizontal resolution of 0.11&#176; (~12 &#215; 12 km) simulated air temperature data, spanning the period 1976&#8211;2100, for the two station sites. Three future emissions scenarios (RCP2.6, RCP4.5 and RCP8.5) were implanted in the simulations after 2005. The observed daily maximum and minimum air temperature data (Tmax and Tmin) from two historical UHI regimes (1976&#8211;1995 and 1996&#8211;2015, respectively) were used, separately, to bias-adjust the model simulations thus creating two sets of results.This novel approach allowed us to assess future temperature developments in Athens under two different UHI intensity regimes. We found that the future frequency of days with Tmax > 37 &#176;C in Athens was only different from rural background values under the intense UHI regime. There is a large increase in the future frequency of nights with Tmin > 26 &#176;C in Athens under all UHI regimes and climate scenarios; these events remain comparatively rare at the rural site.This study shows a large urban amplification of the frequency of extremely hot days and nights which is likely forced by increasing air pollution and heat input. Consequently, local mitigation policies aimed at decreasing urban atmospheric pollution are expected to be also effective in reducing urban temperatures during extreme heat events in Athens under all future climate change scenarios. Such policies therefore have multiple benefits, including: reducing electricity (energy) needs, improving living quality and decreasing heat- and pollution related illnesses/deaths.&#160;

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Impactos das mudanças climáticas na demanda hídrica e duração do ciclo do sorgo forrageiro e feijão-caupi no estado de Pernambuco

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v8.0.p542-559 ◽

2015 ◽

Vol 8 ◽

pp. 542

Author(s):

José Edson Florentino de Morais ◽

Thieres George Freire da Silva ◽

Marcela Lúcia Barbosa ◽

Wellington Jairo da Silva Diniz ◽

Carlos André Alves de Souza ◽

...

Keyword(s):

Climate Change ◽

Relative Humidity ◽

Air Temperature ◽

Water Demand ◽

Stomatal Resistance ◽

The State ◽

Extreme Weather Events ◽

Climate Change Scenarios ◽

Area Index ◽

Forage Sorghum

O aumento na ocorrência de eventos climáticos extremos nas últimas décadas é uma forte evidência das mudanças climáticas. Em regiões Semiáridas, onde a pressão de desertificação tem se intensificado, são esperadas diminuição da disponibilidade de água e maior ocorrência de períodos seca, e, consequentemente, efeitos na resposta fisiológica das plantas. Assim, objetivou-se analisar os impactos dos cenários de mudanças climáticas sobre a duração do ciclo fenológico e a demanda de água do sorgo forrageiro e do feijão-caupi cultivados no Estado de Pernambuco. Foram utilizados os valores mensais da normal climatológica brilho solar, temperatura do ar, umidade relativa do ar e velocidade do vento de dez municípios. Considerou-se um aumento de 1,8°C (Cenário B2) e 4,0°C (Cenário A1F1) na temperatura do ar e um decréscimo de 5,0% dos valores absolutos de umidade relativa do ar, além do aumento de 22% na resistência estomática e de 4% no índice de área foliar. Com base nessas informações foram gerados três cenários: situação atual e projeções futuras para B2 e A1F1. Os resultados revelaram uma redução média de 11% (B2) e 20% (A1F1), e de 10% (B2) e 17% (A1F1) na duração do ciclo, e de 4% (B2) e 8% (A1F1), e 2% (B2) e 5% (A1F1) na demanda de água acumulada para o sorgo forrageiro e feijão-caupi, respectivamente. Conclui-se que a magnitude das reduções da duração do ciclo e a demanda de água simulada para as culturas do sorgo forrageiro e do feijão-caupi variaram espaço-temporalmente no Estado de Pernambuco com os cenários de mudanças climáticas.ABSTRACT The increase in the occurrence of extreme weather events in recent decades is a strong evidence of climate change. In semiarid regions, where the pressure of desertification has intensified, are expected to decrease in the availability of water and higher occurrence of drought periods, and, consequently, effects on physiological response of plants. Thus, the objective of analyzing the impacts of climate change scenarios on the duration of phenological cycle and water demand of forage sorghum and cowpea, grown in the State of Pernambuco. Monthly values were used normal climatological solar brightness, air temperature, relative humidity and wind speed of ten municipalities. It was considered an increase of 1.8° C (B2 Scenario) and 4.0° C (A1F1 Scenario) on air temperature and a decrease of 5.0% of the absolute values of relative humidity, in addition to the 22% increase in stomatal resistance and 4% in leaf area index. Based on this information were generated three scenarios: current situation and future projections for B2, A1F1. The results revealed an average reduction of 11% (B2) and 20% (A1F1), and 10% (B2) and 17% (A1F1) for the duration of the cycle, and 4% (B2) and 8% (A1F1), and 2% (B2) and 5% (A1F1) in accumulated water demand for forage sorghum and cowpea, respectively. It is concluded that the magnitude of the reductions in the duration of the cycle and the simulated water demand for crops of forage sorghum and cowpea ranged space-temporarily in the State of Pernambuco with climate change scenarios.

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Alaskan soil carbon stocks: spatial variability and dependence on environmental factors

Biogeosciences Discussions ◽

10.5194/bgd-9-5695-2012 ◽

2012 ◽

Vol 9 (5) ◽

pp. 5695-5718 ◽

Cited By ~ 1

Author(s):

U. Mishra ◽

W. J. Riley

Keyword(s):

Climate Change ◽

Spatial Variability ◽

Soil Carbon ◽

Active Layer ◽

High Latitude ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Soil Wetness ◽

Soc Stocks

Abstract. The direction and magnitude of soil organic carbon (SOC) changes in response to climate change depend on the spatial and vertical distributions of SOC. We estimated spatially-resolved SOC stocks from surface to C horizon, distinguishing active-layer and permafrost-layer stocks, based on geospatial analysis of 472 soil profiles and spatially referenced environmental variables for Alaska. Total Alaska state-wide SOC stock was estimated to be 77 Pg, with 61% in the active-layer, 27% in permafrost, and 12% in non-permafrost soils. Prediction accuracy was highest for the active-layer as demonstrated by highest ratio of performance to deviation (1.5). Large spatial variability was predicted, with whole-profile, active-layer, and permafrost-layer stocks ranging from 1–296 kg C m−2, 2–166 kg m−2, and 0–232 kg m−2, respectively. Temperature and soil wetness were found to be primary controllers of whole-profile, active-layer, and permafrost-layer SOC stocks. Secondary controllers, in order of importance, were: land cover type, topographic attributes, and bedrock geology. The observed importance of soil wetness rather than precipitation on SOC stocks implies that the poor representation of high-latitude soil wetness in Earth System Models may lead to large uncertainty in predicted SOC stocks under future climate change scenarios. Under strict caveats described in the text and assuming temperature changes from the A1B Intergovernmental Panel on Climate Change emissions scenario, our geospatial model indicates that the equilibrium average 2100 Alaska active-layer depth could deepen by 11 cm, resulting in a thawing of 13 Pg C currently in permafrost. The equilibrium SOC loss associated with this warming would be highest under continuous permafrost (31%), followed by discontinuous (28%), isolated (24.3%), and sporadic (23.6%) permafrost areas. Our high resolution mapping of soil carbon stock reveals the potential vulnerability of high-latitude soil carbon and can be used as a basis for future studies of anthropogenic and climatic perturbations.

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Modelling the impacts of European emission and climate change scenarios on acid-sensitive catchments in Finland

Hydrology and Earth System Sciences ◽

10.5194/hess-12-449-2008 ◽

2008 ◽

Vol 12 (2) ◽

pp. 449-463 ◽

Cited By ~ 11

Author(s):

M. Posch ◽

J. Aherne ◽

M. Forsius ◽

S. Fronzek ◽

N. Veijalainen

Keyword(s):

Climate Change ◽

Surface Water ◽

Emission Reduction ◽

General Circulation ◽

General Circulation Models ◽

Chemical Recovery ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Sulphur Deposition ◽

Temperature And Precipitation

Abstract. The dynamic hydro-chemical Model of Acidification of Groundwater in Catchments (MAGIC) was used to predict the response of 163 Finnish lake catchments to future acidic deposition and climatic change scenarios. Future deposition was assumed to follow current European emission reduction policies and a scenario based on maximum (technologically) feasible reductions (MFR). Future climate (temperature and precipitation) was derived from the HadAM3 and ECHAM4/OPYC3 general circulation models under two global scenarios of the Intergovernmental Panel on Climate Change (IPCC: A2 and B2). The combinations resulting in the widest range of future changes were used for simulations, i.e., the A2 scenario results from ECHAM4/OPYC3 (highest predicted change) and B2 results from HadAM3 (lowest predicted change). Future scenarios for catchment runoff were obtained from the Finnish watershed simulation and forecasting system. The potential influence of future changes in surface water organic carbon concentrations was also explored using simple empirical relationships based on temperature and sulphate deposition. Surprisingly, current emission reduction policies hardly show any future recovery; however, significant chemical recovery of soil and surface water from acidification was predicted under the MFR emission scenario. The direct influence of climate change (temperate and precipitation) on recovery was negligible, as runoff hardly changed; greater precipitation is offset by increased evapotranspiration due to higher temperatures. However, two exploratory empirical DOC models indicated that changes in sulphur deposition or temperature could have a confounding influence on the recovery of surface waters from acidification, and that the corresponding increases in DOC concentrations may offset the recovery in pH due to reductions in acidifying depositions.

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Predicting the Suitable Geographical Distribution of Sinadoxa Corydalifolia under Different Climate Change Scenarios in the Three-River Region Using the MaxEnt Model

Plants ◽

10.3390/plants9081015 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1015

Author(s):

Xiaotao Huang ◽

Li Ma ◽

Chunbo Chen ◽

Huakun Zhou ◽

Buqing Yao ◽

...

Keyword(s):

Climate Change ◽

Air Temperature ◽

Habitat Destruction ◽

Distribution Model ◽

Distribution Area ◽

Climate Change Scenarios ◽

Maxent Model ◽

Co2 Concentrations ◽

River Region ◽

Temperature Seasonality

Sinadoxa corydalifolia is a perennial grass with considerable academic value as a rare species owing to habitat destruction and a narrow distribution. However, its distribution remains unclear. In this study, we predicted the distribution of Sinadoxa corydalifolia in the three-river region (the source of the Yangtze River, Yellow River, and Lancang River) under the context of climate change using the maximum entropy (MaxEnt) model. Under the current climate scenario, the suitable distribution mainly occurred in Yushu County and Nangqian County. The suitable distribution area of Sinadoxa corydalifolia covered 3107 km2, accounting for 0.57% of the three-river region. The mean diurnal air temperature range (Bio2), temperature seasonality (Bio4), and mean air temperature of the driest quarter (Bio9) contributed the most to the distribution model for Sinadoxa corydalifolia, with a cumulative contribution of 81.4%. The highest suitability occurred when air temperature seasonality (Bio4) ranged from 6500 to 6900. The highest suitable mean air temperature of the driest quarter ranged from −5 to 0 °C. The highest suitable mean diurnal temperature (Bio2) ranged from 8.9 to 9.7 °C. In future (2041–2060) scenarios, the suitable distribution areas of Sinadoxa corydalifolia from high to low are as follows: representative concentration pathway (RCP)26 (6171 km2) > RCP45 (6017 km2) > RCP80 (4238 km2) > RCP60 (2505 km2). In future (2061–2080) scenarios, the suitable distribution areas of Sinadoxa corydalifolia from high to low are as follows: RCP26 (18,299 km2) > RCP60 (11,977 km2) > RCP45 (10,354 km2) > RCP80 (7539 km2). In general, the suitable distribution will increase in the future. The distribution area of Sinadoxa corydalifolia will generally be larger under low CO2 concentrations than under high CO2 concentrations. This study will facilitate the development of appropriate conservation measures for Sinadoxa corydalifolia in the three-river region.

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Maize leaf development under climate change scenarios

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2010001100001 ◽

2010 ◽

Vol 45 (11) ◽

pp. 1227-1236

Author(s):

Nereu Augusto Streck ◽

Josana Andréia Langner ◽

Isabel Lago

Keyword(s):

Climate Change ◽

Elevated Temperature ◽

Air Temperature ◽

Leaf Development ◽

Flag Leaf ◽

Climate Change Scenarios ◽

Crop Failure ◽

Maize Leaf ◽

Late Emergence ◽

Leaf Appearance

The objective of this work was to simulate maize leaf development in climate change scenarios at Santa Maria, RS, Brazil, considering symmetric and asymmetric increases in air temperature. The model of Wang & Engel for leaf appearance rate (LAR), with genotype-specific coefficients for the maize variety BRS Missões, was used to simulate tip and expanded leaf accumulated number from emergence to flag leaf appearance and expansion, for nine emergence dates from August 15 to April 15. LAR model was run for each emergence date in 100-year climate scenarios: current climate, and +1, +2, +3, +4 and +5°C increase in mean air temperature, with symmetric and asymmetric increase in daily minimum and maximum air temperature. Maize crop failure due to frost decreased in elevated temperature scenarios, in the very early and very late emergence dates, indicating a lengthening in the maize growing season in warmer climates. The leaf development period in maize was shorter in elevated temperature scenarios, with greater shortening in asymmetric temperature increases, indicating that warmer nights accelerate vegetative development in maize.

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An infrared-based coefficient to screen plant environmental stress: concept, test and applications

Functional Plant Biology ◽

10.1071/fp09132 ◽

2009 ◽

Vol 36 (11) ◽

pp. 990 ◽

Cited By ~ 14

Author(s):

Guo Yu Qiu ◽

Kenji Omasa ◽

Sadanori Sase

Keyword(s):

Heat Stress ◽

Water Stress ◽

Environmental Stress ◽

Air Temperature ◽

Canopy Temperature ◽

Water Shortage ◽

Leaf Temperature ◽

Stress Index ◽

Crop Water Stress Index ◽

Water Stress Index

By introducing a reference dry leaf (a leaf without transpiration), a formerly proposed plant transpiration transfer coefficient (hat) was applied to detect environmental stress caused by water shortage and high temperature on melon, tomato and lettuce plants under various conditions. Results showed that there were obvious differences between leaf temperature, dry reference leaf temperature and air temperature. The proposed coefficient hat could integrate the three temperatures and quantitatively evaluate the environmental stress of plants. Experimental results showed that the water stress of melon plants under two irrigation treatments was clearly distinguished by using the coefficient. The water stress of a tomato plant as the soil dried under a controlled environmental condition was sensitively detected by using hat. A linear relationship between hat and conventional crop water stress index was revealed with a regression determination coefficient R2 = 0.97. Further, hat was used to detect the heat stress of lettuce plants under high air temperature conditions (28.7°C) with three root temperature treatments (21.5, 25.9 and 29.5°C). The canopy temperature under these treatments was respectively 26.44, 27.15 and 27.46°C and the corresponding hat value was –1.11, –0.74 and –0.59. Heat stress was also sensitively detected using hat. The main advantage of hat is its simplicity for use in infrared applications.

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Reservoir yield intercomparison of large dams in Jaguaribe Basin-CE in climate change scenarios

RBRH ◽

10.1590/2318-0331.011716033 ◽

2017 ◽

Vol 22 (0) ◽

Cited By ~ 2

Author(s):

Renato de Oliveira Fernandes ◽

Cleiton da Silva Silveira ◽

Ticiana Marinho de Carvalho Studart ◽

Francisco de Assis de Souza Filho

Keyword(s):

Climate Change ◽

Climate Changes ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Global Circulation ◽

Global Circulation Models ◽

Great Divergence ◽

Rainfall Runoff Model ◽

The Impact ◽

Reservoir Yield

ABSTRACT Climate changes can have different impacts on water resources. Strategies to adapt to climate changes depend on impact studies. In this context, this study aimed to estimate the impact that changes in precipitation, projected by Global Circulation Models (GCMs) in the fifth report by the Intergovernmental Panel on Climate Change (IPCC-AR5) may cause on reservoir yield (Q90) of large reservoirs (Castanhão and Banabuiú), located in the Jaguaribe River Basin, Ceará. The rainfall data are from 20 GCMs using two greenhouse gas scenarios (RCP4.5 and RCP8.5). The precipitation projections were used as input data for the rainfall-runoff model (SMAP) and, after the reservoirs’ inflow generation, the reservoir yields were simulated in the AcquaNet model, for the time periods of 2040-2069 and 2070-2099. The results were analyzed and presented a great divergence, in sign (increase or decrease) and in the magnitude of change of Q90. However, most Q90 projections indicated reduction in both reservoirs, for the two periods, especially at the end of the 21th century.

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Projected Future Temporal Trends of Two Different Urban Heat Islands in Athens (Greece) under Three Climate Change Scenarios: A Statistical Approach

Atmosphere ◽

10.3390/atmos11060637 ◽

2020 ◽

Vol 11 (6) ◽

pp. 637 ◽

Cited By ~ 1

Author(s):

Tim van der Schriek ◽

Konstantinos V. Varotsos ◽

Christos Giannakopoulos ◽

Dimitra Founda

Keyword(s):

Climate Change ◽

Air Pollution ◽

Air Temperature ◽

Temporal Trends ◽

Temperature Data ◽

Rural Site ◽

Future Climate Change ◽

Climate Change Scenarios ◽

The Future ◽

The Impact

This is the first study to look at future temporal urban heath island (UHI) trends of Athens (Greece) under different UHI intensity regimes. Historical changes in the Athens UHI, spanning 1971–2016, were assessed by contrasting two air temperature records from stable meteorological stations in contrasting urban and rural settings. Subsequently, we used a five-member regional climate model (RCM) sub-ensemble from EURO-CORDEX with a horizontal resolution of 0.11° (~12 × 12 km) to simulate air temperature data, spanning the period 1976–2100, for the two station sites. Three future emissions scenarios (RCP2.6, RCP4.5, and RCP8.5) were implanted in the simulations after 2005 covering the period 2006–2100. Two 20-year historical reference periods (1976–1995 and 1996–2015) were selected with contrasting UHI regimes; the second period had a stronger intensity. The daily maximum and minimum air temperature data (Tmax and Tmin) for the two reference periods were perturbed to two future periods, 2046–2065 and 2076–2095, under the three RCPs, by applying the empirical quantile mapping (eqm) bias-adjusting method. This novel approach allows us to assess future temperature developments in Athens under two UHI intensity regimes that are mainly forced by differences in air pollution and heat input. We found that the future frequency of days with Tmax > 37 °C in Athens was only different from rural background values under the intense UHI regime. Thus, the impact of heatwaves on the urban environment of Athens is dependent on UHI intensity. There is a large increase in the future frequency of nights with Tmin > 26 °C in Athens under all UHI regimes and climate scenarios; these events remain comparatively rare at the rural site. This large urban amplification of the frequency of extremely hot nights is likely caused by air pollution. Consequently, local mitigation policies aimed at decreasing urban atmospheric pollution are expected to be highly effective in reducing urban temperatures and extreme heat events in Athens under future climate change scenarios. Such policies directly have multiple benefits, including reduced electricity (energy) needs, improved living quality and strong health advantages (heat- and pollution-related illness/deaths).

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