A brief discourse on the need for adaptive strategies to climate change and the concomitant extreme weather events
By Alfred Kamupingene
Evidence of climate change is mounting and the melting of icebergs at the north pole is further proof of that. Although models on climate change, extreme weather and catastrophic events and the magnitudes thereof have not yet won consensus, that the climate is drifting away from the norm, what we have come to know, is beyond any shred of doubt.
The myriad of factors accounting for this include levels of carbon dioxide in the atmosphere mainly due to emission from the industrialized parts of the world and the ozone depletion caused by the same stressor.
Carbon dioxide helps to keep the earth warm, lest we freeze, however an excessive amount of it in the atmosphere leads to over-heating of the earth.
On the other hand, ozone or three-oxygen molecule gas shields us from ultra-violet rays as the latter has the capacity to cause cancer.
Recent research has shown that Africa is one of the most vulnerable continents to climate change and climate variability, as the situation in Africa is aggravated by the interaction of multiple stressors occurring at various levels and weak adaptive capacity.
The mounting evidence of climate change and variability have necessitated an impact-led approach as well as a vulnerability-led approach in other parts of the world. The aforesaid approaches are contingency plans for mitigating and minimizing the adverse impacts of the impending climate change and variability while selectively reinforcing the positive ones.
The changing climate and elevated atmospheric carbon dioxide are expected to negatively impact evapotranspiration, precipitation and available water supply.
In fact, warmer conditions lead to increased rates of evaporation and transpiration and can potentially inhibit condensation.
Thus, potentially, climate change will decrease the supply of water available for agriculture while at the same time it increases demand.
Countries like Namibia have an additional degree of dependency on water as the bulk of the domestic power generation capacity is hydro. Therefore, an effective model of climate change that combines weather scenarios with supply and water demand simulations will help regions in their planning and give the central government a tool for evaluating different policy options/choices.
The essence of knowledge or mere awareness of the impact of global climate change and variability transcends the realm of regional and central government policy as it can also inform every economic agent on the best reply.
For instance, economic agents whose economic activities are heavily water-dependent might through such an awareness effect a shift to less water dependent activities. In crop production, this might call for research on or a shift to more drought-resistant crops while in animal husbandry this could prompt stock-breeders to move into small stock farming.
Broadly speaking, such awareness could prompt water demand-side management along the lines of the demand-side management measures we have in place for power consumption.
In general, people who live on arid or semi-arid lands, in low-lying coastal areas, in water limited or flood prone areas are particularly vulnerable to climate variability and change.
Unfortunately, the aforesaid sounds like a description of Namibia’s climate and terrain. The impact of climate change on the fisheries sector is probably better documented and shall be left out of account in this survey.
Given the fact that any material change in weather patterns has far reaching repercussions on many facets of the economy, the imperatives are that nations build adaptive and absorption capacities to such phenomena.
Nations need to absorb the concomitant economic shocks that can be triggered by such events and embed adaptation policies in their sustainable development programmes and plans.
Not to do so, especially for countries like Namibia, can lead to huge costs and has the potential of derailing some of the national projects. Therefore any research work on this topic can only be valuable if it includes some strategic policy options and suggestions.
Possible Impact of Climate Change and Variability on Water
Climate change and variability cause pressure on water availability and accessibility due to erratic rainfalls, rising rates of evaporation, transpiration and poor condensation where the latter three are caused by unusually high temperatures.
In their research done in 2002, Hudson and Jones came to the conclusion that by the 2080s the summer air temperature in southern Africa will be 3.7 Celsius degrees higher and 4 Celsius degrees lower during the winter, which actually means warmer summer and cooler winters. Based on current water availability and demand, it is estimated that an abnormally 3 degree higher summer temperature could cause water stress to approximately 120 million people in southern Africa by 2055.
In the light of the above, gaining a better understanding of the complex mechanism responsible for rainfall variability is an imperative.
Changes in the ways these mechanisms influence weather patterns in southern Africa have been studied by Fauchereau and the recent severe droughts in southern Africa are ascribed to El Nino Southern Oscillations (ENSO).
One of the reasons for the seasonal persistence of extended rainfall anomalies in the tropics and sub-tropics lies in the atmospheric circulation and moisture supply modifications by slowly varying surface boundary conditions and most notably Sea Surface Temperatures (SST) where the best example of such SST forcing is the ENSO.
The increasing influence of ENSO on southern African rainfall can also be diagnosed through changes in the statistical association with various ENSO indices over the century.
Fauchereau’s research show a significant correlation between the Southern Africa Rainfall Index (SARI) and the Southern Oscillation Index (SOI) in the December-January-February-March-April (DJFMA) period computed over 20-years running windows from 1990 through 1998.
What stands out is the fact that the ENSO-Southern African rainfall variability relationship is not stationary displaying a close to zero correlation during the 40s and 50s and a significant correlation after the 60s.
It is assumed that some other factors like atmospheric and/or oceanic phenomena might have had a more material bearing prior to the 60s.
Other researches have also highlighted the importance of terrestrial vegetation cover and the associated feedback on physical climate. An increase in vegetation density is suggested to result in a year-round cooling of 0.8 degrees Celsius.
Reason and Mulenga showed that cold Southwest Indian Ocean SST are often associated with dry conditions over southern Africa. This bipolar feature has also been noticed by other researchers.
The bipolar phenomenon suggests that the modifications of the association between southern African rainfall and the ENSO phenomenon are related to long-term changes in the SST background.
Possible Impact of Climate Change and Variability on Agriculture
In an environment of increased temperature and evaporation, the lack of available water decreases soil moisture. Reductions in soil moisture in turn can greatly reduce agricultural yields and lead to poor grazing.
In a word, agricultural production and food security are likely to be severely compromised. In the Namibian context, agriculture is the livelihood of the bulk of the population and second largest employer after the public sector and parastatals taken together.
Therefore, merely looking at the contribution of agriculture to the GDP does not tell the complete story and any negative impact on it has the potential of not only causing stress to food availability but also employment.
Results from various assessments of impacts of climate change on agriculture based on various climate models indicate that southern Africa will experience a reduction in agriculture’s contribution to the GDP of the order of magnitude of 0.4% to 1.3%. While in the case of Namibia, Hannah Reid et al suggest that the negative impact on natural resources alone could reduce Namibia’s GDP by 1% to 6%.
Possible Impact on the Crop Production Sub-sector
In the advanced parts of the world, a standard response or best reply to the climate change, variability and the accompanying limited water availability has been to enhance crop yields through scientific breeding of high-yielding varieties (HYVs). Due to the fact that Africa is the world’s greatest laggard in technological innovation, we tend to leave our destiny in the good hands of fate and live on a prayer. Clearly fate has been very kind to us, but the only question is : how long will it continue to be if our technological innovation remains stationary or move at snail’s pace.
Possible Impact on the Animal
Husbandry/Stock Breeding Sub-sector
The general impact of climate change on livestock farming in Africa was investigated by Seo and Mendelssohn. They showed that small stocks are more heat-tolerant as a result of which losses to small stock farmers are lower than those to large stock farmers.
Increased precipitation of 14% would be likely to reduce the income of small stock farms by 10% mostly due to a reduction in the number of animals kept.
The same reduction in precipitation would be likely to reduce the income of large stock farms by approximately 9%, due to reduction in both stock numbers and in net revenue per animal. Increased precipitation is likely to be harmful to grazing animals because it implies a shift from grassland to forests and an increase in harmful disease vectors.
Possible Impact of Climate Change and Variability on Energy
Any adverse climate change can have a doubly-negative impact on Namibia’s energy capacity. For the rural population, and which makes up close to 70% of the population, poor rainfalls that can cause deforestation which in turn can reduce their main source of energy, firewood. The urban population will also be impacted upon through power scarcity as 63% of the country’s own source of energy is hydro.
Conclusions Which Can Be Drawn from the Discussion Above
The frequency and magnitude of extreme weather events may increase in the future, due to climate change. Therefore, unless climate change proof and adaptation measures are put in place, an arid and semi-arid country like Namibia will experience an increasing vulnerability. Namibia is triply-prone to climate variability. First, water resources which are a function of erratic rainfalls have a huge bearing on potable water, crop production and animal husbandry; and second, Namibia’s own power generation capacity is primarily hydro.
Under this scenario Namibia can mitigate the impact of climate variability by:
1) reduce dependency on water were possible. For instance technological advancement can help develop drought resistant and yet high yielding varieties.
2) climate change leads to lower soil moisture and that in turn has an adverse effect on grassland. Moving from livestock were grass is a major intake can make livestock farming more resilient.
3) demand-side water management policies akin to the power demand-side management measure can lead to efficient utilization of this scare and yet indispensable resource.
4) building human capital in , meteorology and agro-meteorology, can help Namibia develop its own dynamic GCMs.
5) climate change can lead to a material reduction in water availability and poor rainfalls and those can constraint energy sources for the urban and rural populations of Namibia correspondingly.
Our strategic policies should therefore be aimed at curtailing our dependency on those sources. The urban population should reduce its reliance on water generated power while the rural population should explore biotechnology sources or solar energy.
Due to its quantum, such an idea is beyond household capacities and should be envisaged as a National project.
6) Namibia has National Resource Accounts which provide information on the contribution of a number of natural resources to GDP. Satellite accounts have also been developed for assets like livestock (Lange, 1998), fish (Lange and Motinga, 1997), forest (Barnes, 2005), wildlife (Barnes, 2004), water (Lange,1998), energy (Stage and Fleermuys, 2003) and minerals( Lange and Motinga, 1997).
What is now required is the development of models which gauge the potential impact of adverse climatic changes on each one of those assets and how that eventually will impact economic growth.
This undertaking has to be multi-disciplinary as now single discipline can cover all the pertinent issues exhaustively.
Alfred Kamupingene is the Director of Research, Namibia Equity Brokers
Tel: 061-25 6666
Cell: 0811 27 1989