in pasture quality, which can make it more difficult for livestock to recover from the effects of a one-off drought.

## **At the other extreme, floods are also a significant risk to Uruguay's economy, especially in the low-lying**

**areas of the country.** Floods can cause significant damage to crops, pasture, and infrastructure, leading to losses in production and increased costs. For example, flooding can lead to soil erosion, which can reduce the quality and productivity of the land. Additionally, floods can impact transport and logistics, making it more difficult and expensive to move goods to markets.

# 3.1. Future climate conditions for the country are uncertain, particularly for precipitation patterns

**The potential future impact of climate change on hydrometeorological**<sup>**5**</sup> **events is highly uncertain, for**

**several reasons** . The most important source of uncertainty is establishing the trajectory of global emissions for the next decades, which depend on factors like the evolution of low-carbon technologies, the changes in global policies for decarbonization, social attitudes towards climate change, etc. We assess future climate scenarios using Representative Concentration Pathways (RCP), which describe different trajectories for emissions and concentrations of the full suite of greenhouse gases (GHG) and aerosols and chemically active gases, as well as land use/land cover. These RCP pathways are the standard tool to present alternative future scenarios, and we use this convention in the following sections.

**The standard RCP pathways considered in World Bank climate-aware macroeconomic analysis are** :

- RCP2.6 represents a pathway where greenhouse gas emissions are strongly reduced, resulting in a best estimate global average temperature rise of 1.6°C by 2100 compared to the pre- industrial period.

- RCP4.5 is an intermediate stabilization pathway corresponding to slowly reducing carbon emissions, with a best estimate global average temperature rise of 2.4°C by 2100.

- RCP8.5 is a pathway where greenhouse gas emissions continue to grow unmitigated, leading to a best estimate global average temperature rise of 4.3°C by 2100.

## **At the level of the physical atmospheric science, projections of climate variables such as temperature**

**and precipitation for a given RCP pathway are also subject to uncertainty** . As with any other modeling exercise, different modeling approaches will not yield exactly the same results. This is particularly the case for climate processes that occur at smaller scales, where large Earth models need to adopt simplifying assumptions. The Coupled Model Intercomparison Project (CMIP) maintains a continuous effort to update and compare the results of different models which is “useful for understanding which results are consistent across models, and which results are less agreed upon.”<sup>6</sup>

**The literature on climate projections tends to show stronger patterns and agreement for temperature trends than for precipitation** . This is also true for Uruguay and adjacent climatic zones. As shown in Figure 4 and Figure 5, the multi-model averages of CMIP show large additional increases in temperatures for the country, predicting almost 4°C higher temperature by 2100 in the very extreme conditions of RCP 8.5 and

> 5 Hazards that involve the transfer of water and energy between the land surface and the lower atmosphere. These are caused by extreme meteorological and climate events such as floods or droughts. 6 https://wcrp-cmip.org/cmip-overview/

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