Category: Country

Climate change threatens the health and sanitation sector through more frequent incidences of heatwaves, floods, droughts and dry winds [32]. Climate change impacts on health can be direct, e.g. via increasing exposure to heatwaves or floods, or indirect, e.g. via more frequent incidences of vector-borne diseases, such as malaria, as well as via increasing food insecurity or malnutrition.

Heatwave exposure and mortality

Rising temperatures will result in more frequent heatwaves in Ghana, which will increase heat-related mortality. Under RCP6.0, the population affected by at least one heatwave per year is projected to rise from 5 % in 2000 to 19 % in 2080 (Figure 17). Furthermore, under RCP6.0, heat-related mortality will likely increase from about 1 to about 5 deaths per 100 000 people per year, which translates to an increase by a factor of more than five towards the end of the century compared to year 2000 levels, provided that no adaptation to hotter conditions will take place (Figure 18). Under RCP2.6, heat-related mortality is projected to increase to about 2 deaths per 100 000 people per year.

Among the key health challenges in Ghana are also communicable diseases, such as malaria, tuberculosis, and HIV, maternal and children’s health as well as malnutrition, many of which are expected to become increasingly severe under climate change. Studies show that Malaria, diarrhea, and Cerebro Spinal Meningitis are being aggravated by impacts of climate change in Ghana [33].

References

[32] A. Haines, R. S. Kovats, D. Campbell-Lendrum, and C. Corvalan, “Climate change and human health: Impacts, vulnerability and public health,” Public Health, vol. 120, no. 7, pp. 585–596, Jul. 2006.
[33] D. B. K. Dovie, M. Dzodzomenyo, and O. A. Ogunseitan, “Sensitivity of health sector indicators’ response to climate change in Ghana,” Sci. Total Environ., vol. 574, pp. 837–846, Jan. 2017.

Climate change is anticipated to have a significant influence on the ecology and distribution of tropical ecosystems, though the magnitude, rate and direction of these changes are uncertain [29]. Under rising temperatures, increased frequency and intensity of droughts and shorter growing periods, wetlands and riverine systems become at risk of being converted to other ecosystems with plants being succeeded and animals losing habitats. Increased temperatures and droughts can also affect succession in forest systems while concurrently increasing the risk of invasive species, all of which affect the ecosystems. In addition to these climate drivers, reduced agricultural productivity and population growth might motivate further agricultural expansion resulting in increased deforestation, forest degradation and in return in increased forest fires, all of which will impact animal and plant biodiversity [30]. While ecosystems in the northern areas of Ghana are expected to be particularly affected given the higher expected temperature increase and mounting pressure from human land use, the challenges are prevalent throughout the entire country.

Species richness

Model projections of species richness (including amphibians, birds, and mammals) and tree cover for Ghana are shown in Figure 16 and 17, respectively. The volatility in species richness between 2030 and 2050 under RCP6.0 suggest a high sensitivity of species survival and population recovery to natural climate variability. Overall, however, model results indicate a slightly positive long-term impact of climate change on species richness under both RCPs (Figure 15), with the majority of models (at least 75 %) agreeing on this trend.

Tree cover

With regards to tree cover shifts, model results are highly uncertain. Until mid-century, tree cover is projected to not change significantly in most parts of Ghana. Towards the end of the century, the average model projects slight decreases of tree cover under RCP2.6 and slight increases under RCP6.0, yet model agreement about these trends is low in most parts of the country (Figure 16).

Although these results paint an overall positive picture for climate change impacts on ecosystems and biodiversity, it is important to keep in mind that the model projections exclude any impacts on biodiversity loss from human activities such as land use, which have been responsible for significant losses of global biodiversity in the past, and are expected to remain the main driver of biodiversity loss in the future [31].

[28] T. M. Shanahan et al., “CO2 and fire influence tropical ecosystem stability in response to climate change,” Sci. Rep., vol. 6, no. 1, p. 29587, Jul. 2016.
[29] S. Agyemang, M. Muller, and V. R. Barnes, “Fire in Ghana’s dry forest: Causes, frequency, effects and management interventions,” in Proceedings of the large wildland fires conference, 2014, pp. 15–21.
[30] IPBES, “Global Assessment Report on Biodiversity and Ecosystem Services,” Bonn, 2019.

Extreme weather events have been the cause of major damage to the infrastructure sector in Ghana in the past. A study by Twerefou et al. [25] from 2014, for example, states that within one year, 1016 km of roads were destroyed, 13 bridges collapsed and 442 sewers damaged in the northern region of Ghana in 2007 alone through climate-related events. In general, high temperature can cause roads to develop cracks, while high precipitation rates may create potholes or deepen existing ones. [26]. Transport infrastructure is very vulnerable to extreme weather events and yet very important for social, economic and agricultural livelihoods. Roads allow communities to trade their goods and access healthcare, education, credit, as well as other services, especially in rural and remote areas of Ghana.

Storms, extreme rainfall and floods can also have devastating effects on economic production sites as well as settlements, especially in areas where large populations reside, such as Accra, Kumasi and Tamale. Informal settlements are particularly vulnerable to these events, as structures are generally weak and dwellers have low adaptive capacity to respond to disruptive events. Hydropower generation plants are affected by both droughts and floods, whereas sea level rise is already beginning to erode coastal roads [27]. Overall, climate change will make the life span of infrastructure shorter than planned while maintenance costs will increase significantly to keep them functioning [27], [28].

Under climate change, extreme weather events are likely to become more frequent, and temperatures are projected to rise. Accordingly, the risk for infrastructure damage in the country is likely to increase. However, precise predictions of the location and extent of exposure are difficult to make. For example, projections of river flood events are subject to substantial modelling uncertainty, largely due to the uncertainty of future projections of precipitation amounts and their spatial distribution, affecting affecting flood occurrence (see also Figure 5). According to this analysis, flood projections show a decrease in exposure for one climate model, no change for another, a slight increase for the third and a strong increase for the fourth. Thus, no reliable estimates on river flood occurrence in the future can be made. While median model trends suggest an approximate doubling of road exposure to floods under RCP6.0 (Figure 13) from 2000 to 2080, the very likely range of model results indicates a possibility of up to a fivefold increase in road exposure to floods by 2080 (from 0.2 % of the national road network exposed in 2000 to 1.1 % in 2080). Also urban land area exposed to floods is projected to increase (Figure 14), with a very likely range of 0–0.6 % of the urban area exposed by 2080 under RCP 6.0.

Twerefou et al. [27] estimate that the future (2020-2100) cost of climate change-related damage on road infrastructure will amount to USD 473 million if no adaptation actions are taken, and USD 678.47 million if pricing in the costs for adaptation efforts in designing and constructing new road infrastructure. They estimate that the highest adaptation costs will incur in the northern region and the lowest in the greater Accra region.

With the impact to GDP from heatwaves projected to increase from around 5 % in 2000 to 15 % (RCP2.6) and 20 % (RCP6.0) by the end of the century, it is recommended that policy planners start identifying heat-sensitive economic production sites and activities, and integrating climate adaptation options, such as improved, solar-powered cooling systems or switching of operation times from day to night.

References

[25] D. Twerefou, K. Adjei-Mantey, and N. Strzepek, “The economic impact of climate change on road infrastructure in sub-Saharan Africa countries: evidence from Ghana,” 2014.
[26] M. Taylor and M. Philp, “Adapting to climate change-implications for transport infrastructure, transport systems and travel behaviour,” Road Transp. Res., vol. 19, no. 4, 2011.
[27] D. Twerefou, K. Adjei-Mantey, and N. Strzepek, “The economic impact of climate change on road infrastructure in sub-Saharan Africa countries: evidence from Ghana,” World Institute for Development Economics Research. Helsinki, Finland, 2014.

Agriculture is amongst the sectors most exposed to climate change. Smallholder farmers in Ghana are increasingly challenged by the uncertainty and variability of weather that climate change causes, particularly in the northern regions of Ghana. Since crops are predominantly rainfed (as less than 1 % of the national crop area is irrigated), crop yields depend on water availability and are susceptible to drought. The impacts of climate change on the agricultural sector will be crop-specific and also site-specific with major negative impacts expected for maize in the central to northern parts of the country [24]. Yet, the high uncertainty of water availability projections (Figure 10) translates to high uncertainty in drought projections (Figure 11). According to the median over all models employed for this analysis, the national crop land area exposed to at least one drought per year will hardly change in response to global warming. However, there are models that project an increase in drought exposure. Under RCP6.0, the likely range of drought exposure of the national crop land area per year widens from 0.3–8.8 % in 2000 to 0.5–21.0 % in 2080. The very likely range widens from 0.1–25.0 % in 2000 to 0.1–53.0 % in 2080. This means that some models project more than a doubling of drought exposure over this time period, while others project no change.

In terms of yield projections, model results indicate a clear negative yield trend for maize and millet under both RCP2.6 and RCP6.0. As a best estimate, compared to year 2000, yields averaged over the whole country are projected to decline by 9% for maize and 10% for millet by 2080 under RCP6.0, and by 4% and 5% under RCP2.6, respectively. Yields of cassava, groundnuts and field peas, on the other hand, are projected to significantly gain from climate change. Under RCP6.0, yield increases by 2080 relative to year 2000 are projected to amount to 33% for cassava, 14% for field peas, and 3% for groundnuts. A possible explanation for the positive results under RCP6.0 is that cassava, groundnuts and field peas are so-called C3 plants, which follow a different metabolic pathway than maize and millet (which are C4), and thus benefit more from the CO2 fertilization effect under higher concentration pathways. Cassava and groundnuts are also more tolerant to both low and high rainfall extremes.

[24] L. Murken et al., “Climate Risk Analysis for Identifying and Weighing Adaptation Strategies in Ghana,” 2019.

A significant number of households (~40 %) depend on groundwater especially in the north [20], [21]. In particular after mid-century, climate change will reduce the recharge into groundwater reservoirs (aquifers), while increased requirements for agricultural water use under dry periods can lead to water scarcity. This risk is significant for closed basins such as Lake Bosomtwi, which has a small catchment [22]. In the south, sea level rise and storm surges will also increase the risk of salt water intrusion in freshwater especially in aquifers. Model results from the literature for the impacts of climate change on the Volta river basin in Ghana indicate that extreme flows will be more frequent [23], [24]. This means there is a likely increase of periods with either relatively higher or lower mean annual discharge than in the past, sometimes in consecutive years, affecting availability of fresh water for agriculture, sanitation, generation of hydropower and other economic activities.

Per capita water availability

Current projections for water availability in Ghana display high uncertainty under both GHG emissions scenarios. Assuming a onstant population level, multi-model median projections suggest a slight decline in per capita water availability over Ghana by the end of the century under both RCP2.6 and RCP6.0 (Figure 9). Yet, when accounting for population growth according to SSP2 projections², per capita water availability for Ghana is projected to decline by about 70 % by 2080 relative to year 2000 (Figure 9, B). While this decline is not primarily driven by climate change but population growth, it highlights the urgency to invest in water saving measures and technologies for future water consumption.

Spatial distribution of water availability

Looking at the spatial distribution of future water availability projections within Ghana, it becomes evident that water saving measures will become especially important after 2050 in the north of the country (Figure 10). For all other parts of Ghana, water availability projections are too uncertain to make any such statement.

² Shared Socio-economic Pathways (SSPs) outline a narrative of potential global futures, including estimates of broad characteristics such as country-level population, GDP, or rate of urbanisation. Five different SSPs outline future realities according to a combination of high and low future socio-economic challenges for mitigation and adaptation. SSP2 represents the “middle of the road”-pathway.

References

[20] P. Gyau-Boakye and S. Dapaah-Siakwan, “Groundwater as source of rural water supply in Ghana,” J. Appl. Sci. Technol., vol. 5, no. 1, pp. 77–86, 2000.
[21] E. Obubie and B. Barry, “Ghana,” in Groundwater availability and use in Sub-Saharan Africa: a review of 15 countries, P. Pavelic, M. Giordano, B. Keraita, T. Rao, and V. Ramesh, Eds. Colombo, Sri Lanka: International Water Management Institute (IWMI), 2012, p. Ch. 4, pp.43–64.
[22] B. F. Turner, L. R. Gardner, and W. E. Sharp, “The hydrology of Lake Bosumtwi, a climate-sensitive lake in Ghana, West Africa,” J. Hydrol., vol. 183, no. 3–4, pp. 243–261, Sep. 1996.
[23] K. Owusu, P. Waylen, and Y. Qiu, “Changing rainfall inputs in the Volta basin: implications for water sharing in Ghana,” GeoJournal, vol. 71, no. 4, pp. 201–210, Apr. 2008.
[24] L. Murken et al., “Climate Risk Analysis for Identifying and Weighing Adaptation Strategies in Ghana’s Agricultural Sector,” 2019.

Effective post-harvest management is crucial to avoid food loss along the value chain. Investments in scaling technologies for improved post-harvest management have high potential for reducing crop losses, also and especially under climate change. With climate change altering growing and harvesting seasons, post-harvest management is important to cope with increased uncertainty. It is a risk-reducing strategy that lowers the vulnerability of crop production to climate impacts. Next to main staple crops such as maize and beans, post-harvest loss (PHL) of easily perishable horticulture crops could be avoided. Numerous effective and low-cost technologies exist that can prevent or reduce PHL.

Ghana’s NDC Implementation and Investment plan lists post-harvest management as a priority for adapting agriculture to climate change, with interviews confirming wide-spread interest in such strategies. A concrete post-harvest technology with promising results in the context of maize production in Ghana have been so-called PICS bags (Purdue Improved Cowpea Storage): simple and affordable yet effective hermetic storage bags originally developed for storing cowpea. Implementation of improved post-harvest management strategies can be recommended across the country as a low-hanging fruit, since better post-harvest management can increase agricultural production considerably.

Furthermore, as the economic analysis confirmed, most post-harvest management measures are rather low cost interventions, with most intervention types being “no regret” strategies because even in the absence of climate change, the improvement in crop handling will lead to lower crop losses and higher agricultural output, being economically sensible. Figure 1 shows the net value of maize production under different post-harvest management scenarios, compared to scenarios of maize production without adaptation – both with (CC) and without climate change (BAS). Except for the highest cost scenario (MAX), all other PHM scenarios do not only make up for the maize losses under climate change, but are also able to surpass maize production under the baseline scenario (without climate change and without adaptation). This shows their high economic viability.

Overall, post-harvest management strategies have considerable potential in Ghana and, being an often low-cost and no-regret strategy, can be recommended for wider implementation.

Temperature

In response to increasing greenhouse gas (GHG) concentrations, air temperature over Ghana is projected to rise by 0.7 – 2.7°C (very likely range) by 2080 relative to year 2000, depending on the future GHG emissions scenario. Compared to 2000 levels, median climate model temperature increases over Ghana amount to approximately 0.8°C in 2030, 1.1°C in 2050, and 1.2°C in 2080 under the low emissions scenario RCP2.6. Under the medium/high emissions scenario RCP6.0, median climate model temperature increases amount to 1.0°C in 2030, 1.5°C in 2050, and 2.3°C in 2080.

Very hot days

In line with rising annual mean temperatures, the annual number of very hot days (days with daily maximum temperature greater than 35°C) is projected to rise substantially in particular over northern Ghana. Under the medium/high emission scenario RCP6.0, on average over all of Ghana, the median climate model projects 34 more very hot days per year in 2030 than in 2000, 55 more in 2050, and 94 more in 2080. In some parts, especially in the North of Ghana, this amounts to about 300 days per year by 2080.

Sea level rise

In response to globally increasing temperatures, the sea level off the coast of Ghana is projected to rise. Until 2050, very similar sea levels are projected under different GHG emissions scenarios. Under RCP6.0 and compared to year 2000 levels, the median climate model projects a sea level rise by 11 cm in 2030, 20 cm in 2050, and 39 cm in 2080. This threatens Ghana’s coastal communities and may cause saline intrusion in coastal waterways and groundwater reserves.

Precipitation

Future projections of precipitation are substantially more uncertain than projections of temperature or sea level rise. Detecting trends in annual mean precipitation projections is complicated by large natural variability at multi-decadal time scales and considerable modelling uncertainty (Figure 5). Of the four climate models underlying this analysis, one projects a decline in annual mean precipitation over Ghana. According to the other three models, there will be no change. Therefore, our best estimate is that there will be almost no change in total precipitation per year until 2080 irrespective of the emissions scenario, yet this result is highly uncertain.

Heavy precipitation events

In response to global warming, extreme precipitation events are expected to become more intense in many parts of the world due to the increased water vapor holding capacity of a warmer atmosphere. At the same time, the number of days with heavy precipitation is expected to increase. This tendency is also found in climate projections for Ghana, with climate models projecting a slight increase in the number of days with heavy precipitation events, from 7 days/year in 2000 to 8 days/year under RCP2.6 or 9 days/year under RCP6.0 by 2080. Central Ghana is subject to increased heavy precipitation, while for the far north, no change is projected by the multi-model mean.

Soil moisture

Soil moisture is an important indicator for drought conditions. In addition to soil parameters, it depends on both precipitation and evapotranspiration and therefore also on temperature as higher temperature translates to higher potential evapotranspiration. Annual mean top 1-m soil moisture projections for Ghana show a decreasing tendency. This tendency is stronger than the corresponding precipitation change projections, which reflects the influence of temperature rise on evapotranspiration.

Potential evapotranspiration

Potential evapotranspiration is the amount of water that would be evaporated and transpired if there were sufficient water available at and below the land surface. Since warmer air can hold more water vapor, it is expected that global warming will increase potential evapotranspiration in most regions of the world. In line with this expectation, hydrology projections for Ghana indicate a stronger rise of potential evapotranspiration under RCP6.0 than under RCP2.6. Specifically, under RCP6.0, compared to year 2000 levels, potential evapotranspiration is projected to increase by 3.2% in 2030, 4.6% in 2050, and 7.4% in 2080.

While most adaptation strategies seek to minimize risks stemming from climate change, not all risks can be eliminated. Weather perils such as droughts, storms or erratic precipitation represent so-called systemic risks that go beyond the farmers’ coping ability. Thus, mechanisms are needed that distribute residual risks to avoid that certain groups or individuals lose their livelihoods. One such risk transfer solution is crop insurance, which allows farmers to insure their crop yields against weather-induced losses. While insurance usually is based on indemnity assessment, this model is problematic for smallholder farmers due to the high transaction costs which insurance schemes usually entail. Thus, a more suitable approach for smallholder farmers are weather index-based insurances (WII), a scheme that uses a weather index, such as precipitation, to determine a payout. Alternative index-based insurance schemes can also be useful, such as area-yield index insurance.

Generally, insurance schemes are rather costly adaptation strategies, at least when considering the overall costs and with progressing climate change increasing the overall risk to the agricultural sector. However, insurance schemes have an important role to play for securing livelihoods: They can stabilize farm incomes and can prove to be very cost-effective for farmers when a hazard occurs.

According to the Ghana Agricultural Insurance Pool (GAIP), area-yield index insurance (AYII) as an alternative to WII has shown the biggest potential for smallholder farmers in Ghana as of yet. GAIP is a pioneer in implementing AYII in Ghana, insuring since 2011 successfully some 3000 – 4000 smallholder farmers’ cereal crops^[1] on over 18,000 acres of land. In 2017, GAIP made payouts to nearly half its insured parties.

Although AYII is a promising development, farmers’ uptake of AYII in Ghana remains limited. Balmalssaka et al. (2016), who examined the willingness of farmers in northern Ghana to participate in insurance schemes, found access to credit as well as education and experience with insurance to be important factors determining farmers’ engagement with crop insurance (Balmalssaka et al., 2016).

This indicates the need for additional incentives or financial support for taking out insurance, underlined also by Aidoo et al. (2014) who determined farmers’ willingness to pay for crop insurance in one municipality in Ghana. He concluded there was a need for government subsidies to implement it in the country (Aidoo et al., 2014). While subsidies are one strategy, experts also suggested to bundle insurance with inputs, where possible, to increase uptake.

Overall, crop insurance is a promising strategy for transferring climate risk also in Ghana. There is high interest in Ghana and demand-based roll-out of insurance pilots can be recommended. However, careful design is crucial to ensure affordability and financial sustainability.

[1] The main insured crops are: maize, sorghum, millet and groundnut.

References

• Aidoo, R., James, O., Prosper, W., & Awunyo-Vitor, D., (2014). Prospects of crop insurance as a risk management tool among arable crop farmers in Ghana. Asian Economic and Financial Review, 4(3), 341–354.
• Balmalssaka, Y., Wumbei, B. L., Buckner, J., & Nartey, R. Y., (2016). Willingness to participate in the market for crop drought index insurance among farmers in Ghana. African Journal of Agricultural Research, Vol. 11(14), 1257–1265.