Validation of the Global Environmental Multiscale Model (GEM) for Iran

Abstract The Global Environmental Multiscale Model (GEM) is an integrated forecasting and data assimilation system developed by Environment and Climate Change Canada. The model is currently in operational use for data assimilation and forecasting at global 25 km to 15 km scales; regional 10 km scales over North America; and 2.5 km scales over Canada. To demonstrate the performance of the GEM model for forecasting applications, global forecast outputs of GEM at the 25 km scale were compared to temperature and precipitation datasets collected over an area of 1,648,000 km2 especially representative of the country of Iran on a daily temporal scale. Using the De Martonne method for climate classification and data from 177 meteorological stations, the country of Iran was classified into three zones: an arid zone with 87 stations; a semi-arid zone with 63 stations; and a humid zone with 27 stations. GEM model outputs were compared to observations in each of these demarcated zones. The results show good agreement between modelled and measured daily temperatures with Kling-Gupta efficiencies of 0.76, 0.71 and 0.78 in arid, semi-arid and humid regions respectively, and a moderate agreement between modelled and measured annual precipitation with 50.06%, 35.6% and 15.38% differences in arid, semi-arid and humid regions, respectively. The results also indicate that there is a significant systematic error between the elevation of the stations and the average elevation of corresponding GEM grid cells (13%). The results provide an evaluation of the model performance for Iran to be utilized for climate change applications in a regional context and can serve as a basis for the development of future high-resolution GEM model versions on a global scale.

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GEM-AQ, an on-line global multiscale chemical weather system: model description and evaluation of gas phase chemistry processes

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-14895-2007 ◽

2007 ◽

Vol 7 (5) ◽

pp. 14895-14937 ◽

Cited By ~ 4

Author(s):

J. W. Kaminski ◽

L. Neary ◽

J. Struzewska ◽

J. C. McConnell ◽

A. Lupu ◽

...

Keyword(s):

Multiscale Model ◽

Global Scale ◽

Tropospheric Chemistry ◽

Model Description ◽

Weather System ◽

Gas Phase Chemistry ◽

Global Environmental ◽

On Line ◽

Phase Chemistry ◽

Global Environmental Multiscale

Abstract. Tropospheric chemistry and air quality processes were implemented on-line in the Global Environmental Multiscale model. The integrated model, GEM-AQ, has been developed as a platform to investigate chemical weather at scales from global to urban. The model was exercised for five years (2001–2005) to evaluate its ability to simulate seasonal variations and regional distributions of trace gases such as ozone, nitrogen dioxide and carbon monoxide on the global scale. The model results presented are compared with observations from satellites, aircraft measurement campaigns and balloon sondes.

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Crop adaptation to climate change in the semi-arid zone in Tanzania: the role of genetic resources and seed systems

Agriculture & Food Security ◽

10.1186/2048-7010-3-3 ◽

2014 ◽

Vol 3 (1) ◽

Cited By ~ 19

Author(s):

Ola T Westengen ◽

Anne K Brysting

Keyword(s):

Climate Change ◽

Genetic Resources ◽

Arid Zone ◽

Seed Systems ◽

Adaptation To Climate Change ◽

Crop Adaptation ◽

Semi Arid

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Households’ Adaptation to Climate Change Hazards in Semi-Arid Region of Mopani, South Africa

10.5772/intechopen.94759 ◽

2021 ◽

Author(s):

Musa Yusuf Jimoh ◽

Peter Bikam ◽

Hector Chikoore ◽

James Chakwizira ◽

Emaculate Ingwani

Keyword(s):

Climate Change ◽

South Africa ◽

Climate Change Adaptation ◽

Urban Areas ◽

Arid Region ◽

Adaptive Systems ◽

Adaptation To Climate Change ◽

Temperature And Precipitation ◽

Semi Arid Region ◽

Semi Arid

New climate change realities are no longer a doubtful phenomenon, but realities to adapt and live with. Its cogent impacts and implications’ dispositions pervade all sectors and geographic scales, making no sector or geographic area immune, nor any human endeavor spared from the associated adversities. The consequences of this emerging climate order are already manifesting, with narratives written beyond the alterations in temperature and precipitation, particularly in urban areas of semi-arid region of South Africa. The need to better understand and respond to the new climate change realities is particularly acute in this region. Thus, this chapter highlights the concept of adaptation as a fundamental component of managing climate change vulnerability, through identifying and providing insight in respect of some available climate change adaptation models and how these models fit within the premises and programmes of sustainable adaptation in semi-arid region with gaps identification. The efforts of governments within the global context are examined with households’ individual adaptation strategies to climate change hazards in Mopani District. The factors hindering the success of sustainable urban climate change adaptation strategic framework and urban households’ adaptive systems are also subjects of debate and constitute the concluding remarks to the chapter.

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Long-Term Impacts of Partial Afforestation on Water and Salt Dynamics of an Intermittent Catchment under Climate Change

Water ◽

10.3390/w12041067 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1067 ◽

Cited By ~ 1

Author(s):

Hossein Daneshmand ◽

Sina Alaghmand ◽

Matteo Camporese ◽

Amin Talei ◽

Pat J.-F. Yeh ◽

...

Keyword(s):

Climate Change ◽

General Circulation ◽

General Circulation Models ◽

Soil Salinization ◽

Tree Planting ◽

Climate Change Scenarios ◽

Global Environmental ◽

Salt Depletion ◽

Hadley Centre ◽

Semi Arid

Soil salinization is a major environmental issue in arid and semi-arid regions, and has been accelerated in some areas by removal of native vegetation cover. Partial afforestation can be a practical mitigation strategy if efficiently integrated with farms and pastures. Using an integrated surface-subsurface hydrological model, this study evaluates the water and salt dynamics and soil salinization conditions of a rural intermittent catchment in the semi-arid climate of southeast Australia subjected to four different partial afforestation configurations under different climate change scenarios, as predicted by several general circulation models. The results show that the locations of afforested areas can induce a retarding effect in the outflow of groundwater salt, with tree planting at lower elevations showing the steadier salt depletion rates. Moreover, except for the configuration with trees planted near the outlet of the catchment, the streamflow is maintained under all other configurations. It appears that under both Representative Concentration Pathways considered (RCP 4.5 and RCP 8.5), the Hadley Centre Global Environmental Model represents the fastest salt export scheme, whereas the Canadian Earth System Model and the Model for Interdisciplinary Research on Climate represent the slowest salt export scheme. Overall, it is found that the location of partial afforestation generally plays a more significant role than the climate change scenarios.

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The Impacts of Human Activities on Ecosystems within China’s Nature Reserves

Sustainability ◽

10.3390/su11236629 ◽

2019 ◽

Vol 11 (23) ◽

pp. 6629

Author(s):

Ping Zhu ◽

Wei Cao ◽

Lin Huang ◽

Tong Xiao ◽

Jun Zhai

Keyword(s):

Climate Change ◽

Human Activities ◽

Arid Zone ◽

Ecosystem Dynamics ◽

Tibet Plateau ◽

Warm Temperate Zone ◽

Nighttime Light ◽

Qinghai Tibet Plateau ◽

Warm Temperate ◽

Semi Arid

Protected areas (PAs) provide refuges for threatened species and are considered to be the most important approach to biodiversity conservation. Besides climate change, increasing human population is the biggest threat to biodiversity and habitats in PAs. In this paper, the temporal and spatial variations of land cover changes (LCC), vegetation fraction (VFC), and net primary productivity (NPP) were studied to present the ecosystem dynamics of habitats in 6 different types of national nature reserves (NNRs) in 8 climate zones in China. Furthermore, we used Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light datasets and the human disturbance (HD) index estimated from LCC to quantify the living and developing human pressures within the NNRs in the period 2000–2013. The results showed that (1) the living human activities of NNRs increased apparently in the humid warm-temperate zone, Qinghai-Tibet Plateau, mid-temperate semi-arid zone, and mid-temperate humid zone, with the highest increase of nighttime light observed in inland wetlands; (2) the developing human activities in NNRs indicated by the HD index were higher in the humid warm-temperate zone and mid-temperate semi-arid zone as a result of increasing areas of agricultural and built activities, and lower in the sub-tropics due to improved conservation of forest ecosystems; (3) the relationship between HD and VFC suggests that ecosystems in most NNRs of south-subtropics, mid-temperate arid zone and Qinghai-Tibet Plateau were predominantly impacted by climate change. However, HDs were the prevalent factor of ecosystem dynamics in most NNRs of north-subtropics, mid-temperate semi-arid and humid zones.

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Evaluation of GPS Precipitable Water over Canada and the IGS Network

Journal of Applied Meteorology ◽

10.1175/jam-2201.1 ◽

2005 ◽

Vol 44 (1) ◽

pp. 153-166 ◽

Cited By ~ 39

Author(s):

Godelieve Deblonde ◽

Stephen Macpherson ◽

Yves Mireault ◽

Pierre Héroux

Keyword(s):

Precipitable Water ◽

Multiscale Model ◽

Geodetic Survey ◽

Tropospheric Delay ◽

Observation Network ◽

Global Environmental ◽

The Mean ◽

The Tropics ◽

Estimated Error ◽

Global Environmental Multiscale

Abstract Precipitable water (PW) derived from the GPS zenith tropospheric delay (ZTD) is evaluated (as a first step toward variational data assimilation) through comparison with that of collocated radiosondes (RS_PW), operational analyses, and 6-h forecasts (from the Canadian Global Environmental Multiscale model) of the Canadian Meteorological Centre. Two sources of ZTD data are considered: 1) final ZTD (over Canada), computed by the Geodetic Survey Division (GSD) of Natural Resources Canada, and 2) final ZTD (distributed globally), obtained from the International GPS Service (IGS). The mean GSD GPS–derived PW (GPS_PW) is 14.9 mm (reflecting the relatively cold Canadian climate), whereas that of the IGS dataset is 20.8 mm. Intercomparison statistics [correlation, standard deviation (SD), and bias] between GPS_PW and RS_PW are, respectively, 0.97, 2.04 mm, and 1.35 mm for the GSD data and 0.98, 2.6 mm, and 0.67 mm for the IGS data. Comparisons of GPS_PW with 6-h forecast PW (TRIAL_PW) show slightly lower correlations and a higher SD. The increase in SD is greater for the IGS data, which is not surprising, because in regions such as the Tropics and subtropics, moisture forecasts are of a lower quality and the RS observation network is sparse. From a three-way intercomparison (IGS GPS_PW, RS_PW, and TRIAL_PW) of the SD statistics, it is found that GPS_PW has the lowest estimated PW error (≈1 mm) for PW in the 5–30-mm range. For PW greater than 30 mm, the RS_PW estimated error is ≈2 mm, and that of GPS_PW is ≈2.5 mm. The TRIAL_PW estimated error increases with PW, reaching 5.5 mm in the 40–55-mm PW range. These intercomparison results indicate that GPS_PW should be a useful source of humidity information for NWP applications.

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Drought and Flood Risk, Impacts and Adaptation Options for Resilience in Rural Communities of Uganda

International Journal of Applied Geospatial Research ◽

10.4018/ijagr.2018010103 ◽

2018 ◽

Vol 9 (1) ◽

pp. 36-50 ◽

Cited By ~ 1

Author(s):

Shuaib Lwasa

Keyword(s):

Climate Change ◽

Rural Communities ◽

Social Economic ◽

Arid Zone ◽

Well Being ◽

Drought Risk ◽

Climate Data ◽

Climate Risks ◽

Droughts And Floods ◽

Semi Arid

Climate change is affecting many rural resource-poor communities unequivocally with differing magnitude, severity and frequency of drought risk from one locale to another especially in Africa. At micro spatial scale of households and villages, climate change risk trends and hazards vary spatially, coupling with social, economic and locational conditions. This paper analyzes vulnerability and impacts of climate change from droughts and floods in a rural community with varied geographies across social, economic and environmental profiles in Uganda. In recent years, studies have shown that droughts have increased form 1 in 10 years to 1 in 6 years and the worst affected area is the semi-arid zone of Uganda that spans from south western through central parts to the north-eastern parts of the country. In the study area of Pallisa, located in the eastern central part of the semi-arid zone, droughts and floods impacts on livelihoods, people and assets are eroding the asset-base for the households. Yet the household assets are important in adaptation and resilience of the community. As a natural resource dependent community like many others, evidence strongly suggests increasing climate risks of droughts and floods the impacts of which are worsening the already grim conditions of community well-being. This paper analyses the climate risks utilizing the vulnerability assessment framework. A scenario-based analysis that integrates community evaluation of vulnerability with climate data to analyze current and future vulnerabilities in a spatial context is conducted to examine spatial differences in vulnerability. Various multi-scale adaptation strategies are analyzed in respect to the climate change risks to assess the resilient capacity of the community to current and future vulnerabilities.

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Verification of High-Resolution Medium-Range Precipitation Forecasts from Global Environmental Multiscale Model over China during 2009–2013

Atmosphere ◽

10.3390/atmos9030104 ◽

2018 ◽

Vol 9 (3) ◽

pp. 104 ◽

Cited By ~ 1

Author(s):

Huating Xu ◽

Zhiyong Wu ◽

Lifeng Luo ◽

Hai He

Keyword(s):

High Resolution ◽

Multiscale Model ◽

Global Environmental ◽

Medium Range ◽

Global Environmental Multiscale

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Calculating groundwater stress and climate change-induced vulnerability of karst aquifers on a global scale

10.5194/egusphere-egu21-929 ◽

2021 ◽

Author(s):

Philipp Nußbaum ◽

Márk Somogyvári ◽

Christopher Conrad ◽

Martin Sauter ◽

Irina Engelhardt

Keyword(s):

Climate Change ◽

Water Stress ◽

Climatic Factors ◽

Karst Aquifer ◽

Global Scale ◽

Stress Index ◽

Karst Aquifers ◽

Climate Zones ◽

Climate Conditions ◽

Temperature And Precipitation

Approximately 10% of the global population rely on groundwater from karst aquifers. Due to complex karst structures, these aquifers have high infiltration capacities and hydraulic conductivities, which makes them vulnerable to pollution and, as prediction and management are complicated, overexploitation. As populations are growing and demand rises, we assess the current level of groundwater stress in karst aquifers with Mediterranean climates and their vulnerability (defined as the change in groundwater stress) to expected changes in temperature and precipitation on the global scale.Our approach is based on a Groundwater Stress Index (GSI), which is calculated for 356 karst aquifers (as identified in the World Karst Aquifer Map) that have some of their area located in Mediterranean climate zones (Csa, Csb, and Csc after K&#246;ppen/Geiger). GSI are calculated from seven indicators: groundwater recharge, storage, and abstractions, surface runoff, climatic water balance, water-intensity of crops, and groundwater-dependent ecosystems. Each indicator is spatially and temporally averaged to describe a recent trend on aquifer level, resulting in one complex attribute table for the 356 aquifers. GSI is calculated as the average of the normalized indicators for each aquifer, ranging from 0 (no water stress) to 1 (extreme water stress).Aquifers are then grouped based on similarities in two classification parameters &#8211; degree of karstification (P1) and land cover (P2). Comparison of aquifers with similar classification parameters allows to focus more directly on the relationship between groundwater stress and climate, disregarding relatively constant influences. For each group (e.g., well-developed karst, primarily agriculturally used), we plot calculated GSI values with current temperature and precipitation data. By investigating four Shared Socioeconomic Pathways (SSPs) until 2100, we identify aquifers that mimic future climate conditions for others with similar P1 and P2. We then measure the difference in groundwater stress accompanied by altered climatic factors. This change is interpreted as vulnerability to climate change.This approach, which relies on present-day observed conditions, allows us to predict the effect of a changing climate without the need to develop a complex numerical model, which requires large amounts of data and functional understanding of aquifer behavior. While analysis is currently ongoing, we expect both groundwater stress and vulnerabilities to be high. Predicted climate zone shifts by Beck et al. (2018) indicate that, out of 356 karst aquifers with Mediterranean climates, 52 could move to more extreme arid climate zones by 2100.Results will be visualized in the form of vulnerability maps that may serve as an &#8220;early-warning system&#8221;. For particularly threatened aquifers, we will derive recommendations for more sustainable management by suggesting strategies to lower groundwater stress. This is done by taking a closer look at the aquifer&#8217;s indicator values and identifying factors that currently contribute the most to groundwater stress.

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