Studies have shown that Egypt’s climate has changed greatly over the last 10,000 years (Bubenger et al. 2008), changing gradually from a wet climate (rainfall was more than 300 mm/year) to a more arid climate (less than 50 mm/year). Humans had an intimate relationship with their surrounding environment, coexisting with animals like giraffes and elephants, which later disappeared due to the arid climate.
Seasonal temperature distributions in Egypt in the years 2005, 2025, 2050, 2075 and 2100 were studied by Hegazy et al. (2008). According to the study, it is anticipated that temperatures will rise in all four seasons, moving from the southern to the northern parts of Egypt, in the coming 100 years. This change will require the management of the local agro ecosystems in order to adapt planting or sowing practices for the projected climate change scenarios.
The study predicted a contraction in arable land area and a shift in cultivation time. Crop production systems will be under increasing pressure to meet growing national demand in the future. There is also some empirical evidence that higher atmospheric levels of carbon dioxide (CO2) could result in lower protein levels in some grain crops.
The effects of climate change have been documented in the St. Catherine Mountains by monitoring its impact on the disappearance of living organisms on peaks of St. Catherine due to temperature increases. Studies proved that annual changes in temperatures will accelerate the Sinai Baton Blue’s (Pseudophilotes siniacus) risk of extinction. The decline in the Sinai Baton Blue, the smallest butterfly in the world, is due to the decrease in the flowering rate of the Sinai Thyme (Thymus decussatus) by about 40% or more during drought years. Sinai Baton Blue larvae feed on buds, while adult butterflies feed on the flower nectar of the Sinai Thyme. If the temperature continues to rise, the Sinai Thyme will continue to decline in numbers. Furthermore, exposure to additional human threats, such as over grazing and the collection of Sinai Thyme for medical purposes, will further increase the butterfly’s risk of extinction.
Species distribution models are increasingly used for the prediction of the potential distribution of species in response to disturbances or changes resulting from human intervention. Predictive habitat distribution models are used as important tools for assessing the impact of land use changes, climate change and other forms of human interference on different species. Habitat distribution models have proven to be useful for modeling both commonly distributed species (Franklin, 1998) as well as rare species (Wu & Smeins, 2000; Williams et al., 2009).
A limited number of studies have been undertaken to assess the impact of climate change on Egyptian animal and plant species. This may be due to the fact that models are relatively new and the availability of biodiversity data records of Egyptian fauna and flora are sparse and not well organized.
The influence of rising temperatures on the spatial and temporal distribution of four of the major economic crops in Egypt was studied by Hegazy et al., 2008. The species selected for the study were cotton (Gossypium barbadense L., cv. Giza 89), wheat (Triticum aestivum L., cv. Gemiza 9), rice (Oryza stiva L., cv. Sakha 101) and maize (Zea mays L., cv. Hybrid 10). Optimum air temperature allowing maximum growth for each of the study crop cultivars and the current and projected air temperature patterns in the future years were used for the projection of the seasonal and crop distribution maps in the years 2005, 2025, 2050, 2075 and 2100.
Results showed that sowing dates of a target crop may be managed in order to allow maximum predicted planting area in the same region. The current maximum area suitable for planting cotton and wheat will be greatly affected by the projected increase in air temperature.
A number of studies have been carried out to model species distributions to assess the effect of climate change on Egypt’s biodiversity, including recent studies that have been carried out to predict the potential distribution of 75 species of Egyptian reptiles. An occupancy model (a type of population viability analysis) was used to assess the potential impacts of global warming on the world’s smallest butterfly, the Sinai Baton Blue (Pseudophilotes sinaicus) of St. Katherine. Maxent was used to test the potential impact of climate change on the distribution of Egyptian antelopes (Barbary Sheep (Ammotragus lervia), Nubian Ibex (Capra nubiana), Dorcas Gazelle (Gazella dorcas), and Slender-horned Gazelle (Gazella leptoceros)) using the A2 and B2 emission scenarios of Global Circulation Models. The effect of climate change on Egyptian butterflies and mammals (using Maxent algorithm and A2 and B2 emission scenarios of a different Global Circulation Model) was discussed and took into consideration the effectiveness of the Egypt’s PA network in conserving Egypt’s biodiversity under current and future climates (using Zonation software). According to modeling studies, it was concluded that some species could lose up to 80% of their home range while others go extinct.
The BioMAP project (http://biomapegypt.org) studied the distribution of each Egyptian butterfly and mammal species. Data on each species were collated from available sources and an actual and predicted distribution map for each species were provided (using Maxent); each species was also assessed according to the IUCN guidelines and criteria. In another study, Maxent was used to predict the potential distribution of the Nubian Ibex (Capra nubiana) in South Sinai, and showed that the presence of water was the environmental factor most influential in their distribution in South Sinai.
The projected impact of modeled climate scenarios (A1B, A2A and B2A) on the distribution of 7 plant species in the arid northwest coastal desert of Egypt by 2040 varied (the modeled species by 2040 varied from species to another. Some of the species were projected to be adversely affected by the changes in climate, while other species are expected to benefit from these changes. The combined impact of the changes in land use and climate pose serious threats to most of the modeled species. The study found that all the species are expected to suffer loss in habitat, except Gymnocarpos decanderus. The results showed that some species, such as Noaea mucronata and Asphodelus aestivus, may suffer serious threats in the area under the combined land use and climate change scenarios. The study highlights the importance of assessing the impact of land use/climate change scenarios on other species of restricted distribution in the area in order to help shape policy and mitigation efforts to protect and preserve biodiversity in Egypt’s deserts.
For more information click here to download.