2023 YIJC J1 MYE

Cluster 2 : Tropical Environments 1. Resource 1 shows the climategraph of La Paz, Bolivia. Resource 2 shows the location of La Paz, Bolivia. Resource 3 shows floods which inundated parts of La Paz, Bolivia. Resource 4 shows deforestation data in La Paz, Bolivia. (a) Cite data from resource 1 to describe the temperature and rainfall patterns of La Paz, Bolivia. (5m)  Aw climate (this is a must point)  Average temperature is 26.6 degrees  Total rainfall is 1666mm  Temperature range is 28.5-25=3.5 degrees  Distinct wet and dry climate  6 months of rainfall above 100 mm between May to October (b) Account for the rainfall pattern of La Paz using resources 1 and 2. (4m)  Explain for the high and the low rainfall  15 degrees North, within the Tropics  Temperatures high between March to April and then from October to November when the region is intercepted by the ITCZ, high rainfall and high temperature, when the trade winds converge – ITCZ, convectional rainfall  Low rainfall, ITCZ moves or shifts away from La Pas to the South region  The movement from 15 degress to 10 degrees, location of La Paz, rainfall for the 3 months  Effect of the ITCZ felt by 5 to 7 degrees (Have to give details of rainfall from the Climate graph and give evidence from Res 2) (Lack of specific infor from Res, to cut up to a maximum of 2marks) (c) Explain the reasons for flooding in La Paz using resources 2, 3 and 4. (5m)  3 reasons – rainfall and ITCZ, high rainfall, convectional rainfall (Res 2)  Urbanisation, concretized floor and roads, lack of infiltration (Res 3)  Deforestation, overland flow increases (Res 4) (All 3 resources must be used specifically, lack of use of res to cut up to a max of 2marks) (d) Account for the effects of floods in La Paz, such as that seen in resource 3. (5m) Effects can be  Social (pple having diarrhoea, spread of diseases, lack of water)  Economic (transport, communication affected, productivity affected, inability to function for a few weeks, depending on the situation etc)  Environment (floods, mosquito breeding, human environment affected) (Have to have at least 2 types of effects, either LT and ST or SEE, make sure that the Res is well described, lack of use of Res to cut up to a max of 2marks)

(e) With reference to resource 4, explain how deforestation can affect stores and flows in the Rio Beni and Rio Mamore basins. (6m)  Stores (lack of interception, no trees, no percolines for water to be infiltrated)  Stores (lack of underground water and also soil moisture storage, lack of infiltration due to impermeable land and also lack of soil or natural ground)  Lack of Baseflow to the rivers  Stores (Channel flow/Lakes/Rivers have more discharge, overland flow and HOF and also floods  Flows (HOF than SOF, higher overland flow))  Flows (Vertical and Lateral Sub-Surface flows will be affected gravely, cease due to the concrete ground, lack of infiltration and so percolation will reduce. Then for throughflow there will be a lack of it due to the impermeable ground and so base flow will eventually reduce).  Higher flows into the rivers (f) Explain 2 measures that you would recommend in La Paz, to manage floods such as the one seen in resource 3. (5m)  Drains (deep, wide channels) or maintain the ones that they may or may not have to cater to increase in water discharges due to heavy rainfall and deforestation  Reafforestation program to reduce flooding in the future, to increase interception storage and also allowo for infiltration and percolation  Channelisation of the 2 Rios (deepen, widen and straighten the river channels especially at the part where La Paz is at) (pls be careful that not all strategies can be used eg: Dams or Land Use Pattern, considering the fact that it is a developing country)

Legend Rivers (Rio) La Paz, Bolivia Resource 3 : Floods in La Paz, Bolivia (2021) Rio Beni Rio Mamore July ITCZ Jan ITCZ

Resource 4 : Deforestation in selected South American countries, (2010-2017)