ghana climate change vulnerability and adaptation assessment

North latitude. Minia (2008) delineated a transitional eco-climatic zone as being farther north (about 7.5-8.5°North) with an average annual total rainfall of 1,301 mm with rain occurring an average of 101 days/year.SRID (2001) indicated the zone encompassed 6,630,000 ha of central Ghana. Rainfall occurs in one peak insome years and two peaks in others, although most years show two peaks (Oppong-Anane, 2001) with majorand minor growing seasons of 200-220 and 60 days, respectively (SRID, 2010). Within this transitional area,most of the tree species are similar to those in the forest zone to the south (Dickson and Benneh, 1988), andoccur in association with tall to medium tall grasses. The soils are fairly fertile and support a wide variety ofcrops.GUINEA SAVANNA ZONEThe Guinea Savanna Zone (also called Tallgrass Savanna Zone or Interior Savanna Zone) lies to the north ofthe Forest-Savanna Transition Zone and is the largest zone, occupying the entire northern half of the country(northern Brong-Ahafo, Northern, Upper West, and Upper East regions, about 14,790,000 ha; SRID, 2010).The zone has an extension through the Akosombo gorge and into the Ho Plains in southwestern Ghana(southern Volta Region). The zone receives an average annual rainfall of about 1,115 mm allocated among anaverage of 99 days/year (Minia, 2008). The Guinea Savanna Zone has one distinct rainy season beginning inlate April or early May, peaking in August-September and abruptly declining in October-November.The rainyseason is followed by a long dry period (Dickson and Benneh, 1988; Oppong-Anane, 2001). The singlegrowing season ranges from 180-200 days (SRID, 2010). Much of the eastern part of the zone lies in therelatively low-lying Volta River Basin, but the northern and western parts of the zone are situated on adissected plateau (the High Plains of the Konkori and Gambarga escarpments) (Owusu-Ansah, 1994). Soilsare generally poor but are most productive in floodplains and along river banks. The vegetation is that ofwooded grassland, consisting of a ground cover of grasses of varying heights interspersed with fire-resistant,deciduous, mostly broad-leaved trees, some of which also occur in the dry semi-deciduous forest type to thesouth. The other dominant feature of the vegetation in the zone is the grasses that grow under and betweenthe trees. Tree cover and tree height decrease from south to north along a decreasing rainfall gradient(Owusu-Ansah, 1994). In their most luxuriant state trees show varying completeness in canopy (Dickson andBenneh, 1988; Benneh and Agyepong, 1990). Likewise, the grasses in the Guinea Savanna Zone are notuniform but differ according to soil type and moisture regime (Oppong-Anane, 2001; MSE, 2002). Thegrasses tend be tall (2-3 m), dense perennial species which, with increased latitude, are replaced by smallerspecies, among which annuals become increasingly common (Owusu-Ansah, 1994). Bare, granitic inselbergsare a typical feature of the savanna landscape. In the dry season, fires, most of which are set by humans, ragethrough the region.SUDAN SAVANNAThe Sudan Savanna (or Short-Grass Savanna) lies to the north of the Guinea Savanna and covers a greaterpart of Burkina Faso and Mali. Like the Forest-Savanna Transition zone, its boundaries are variously drawn.Some (Dickson and Benneh, 1988; MSE, 2002; Oppong-Anane, 2001; Menczer and Quaye, 2006) limit thezone to extreme northeastern Ghana in the Upper East Region in an area variously estimated as 1,900 (SRID,2010), 7,200 (Benneh and Agyepond, 1990), and 10,540 km 2 (MSE, 2002). Minia (2008) delimited a muchbroader eco-climatic belt of Sudan Savanna across northern Ghana, corresponding roughly to the southernboundary of the Upper East Region and the northern half of the Upper West Region (about 10.5° Nlatitude). Given the rather high population pressure in the area, the former small patch in the Upper EastRegion may simply be the result of degradation by man rather than a climatic biome (Oppong-Anane2001). Similarly, the broader belt (Minia, 2008) may likewise simply indicate degradation of Guinea Savannaby poor land use practices. The natural vegetation of the Sudan Savanna Zone is characterized by fire-sweptshort grasses interspersed with low-density woodland of short, low branching, thin-leaved, deciduous speciesthat are drought and fire-resistant (Dickson and Benneh, 1988). Grass cover is sparse and in areas the land isbare and severely eroded (Menczer and Quaye, 2006).GHANA CLIMATE CHANGE VULNERABILITY AND ADAPTATION ASSESSMENT 57