2015年-世界发展银行全球_Water_and_Climate_Adaptation_Plan_for_the_Sava_River_Basin___Annex_6_Guidance_Note_on_Economic_Evaluation_of_Climate_Change_Impacts_in_the_Sava_River_Basin_33页_2mb

Summary of the Water & Climate Adaptation Plan for the Sava River Basin (Annex 6)

Core Content

This document provides a guidance note on the economic evaluation of climate change impacts within the Sava River Basin (SRB), focusing on the agricultural sector and its broader economic implications. The study combines crop modeling with computable general equilibrium (CGE) analysis to assess how climate change affects production, prices, and overall economic growth in the region.

The SRB includes Albania, Bosnia and Herzegovina, Croatia, Macedonia, Serbia, and Slovenia, and the analysis considers five climate models: CLM, HadRM3Q0, RACMO, REMO, and RegCM3. These models project changes in temperature and precipitation, which are then used to simulate the impact on crop yields and prices. The economic baseline (2010–2070) is derived from World Bank, IMF, and USDA forecasts, and serves as a reference for comparing climate change scenarios.

Main Views and Key Information

1. Objective of the Economic Analysis

• To measure the magnitude and distributional costs of climate change impacts and adaptation options.
• To assess the economic implications of climate change at the sector and economy-wide levels.

2. Framework and Basin Overview

• The Sava River Basin spans 95,719 km² and is home to 23 million people.
• It connects three South-European capitals: Ljubljana (Slovenia), Zagreb (Croatia), and Belgrade (Serbia).
• The "Sava River Basin Initiative" was launched in 2001 to promote regional cooperation on sustainable development and water management.

3. Methodology

• The study integrates crop modeling with CGE analysis.
• A mapping between GTAP and FAO classifications was developed to align data for economic modeling.
• Five climate models were used to project changes in temperature and precipitation, which were then translated into yield changes using the WATCAP model.

4. Economic Growth Drivers

• Population growth and total factor productivity (TFP) are key drivers of economic expansion.
• The baseline GDP growth is projected based on historical and forecasted population and productivity data.

5. Climate Change Impact on Crop Yields

• CLM Model: Predicts negative impacts on all crops and countries, with the most significant in Rest of SRB (BIH, Macedonia, Serbia).
• HadRM3Q0 Model: Forecasts more negative impacts than CLM, with Croatia being the most affected.
• RACMO Model: Suggests a slight positive impact on most crops.
• RegCM3 Model: The most optimistic, predicting positive impacts on all crops except Winter Wheat in Croatia and Rest of SRB.
• REMO Model: The most pessimistic, predicting negative impacts across all crops except Winter Wheat in Croatia and Rest of SRB.
• Average impacts across all countries and crops: CLM (-1.3%), REMO (-0.3%), HadRM3Q0 (-0.12%), RACMO (+0.03%), RegCM3 (+0.41%).

6. Climate Change Impact on Crop Prices

• Prices for most crops are expected to rise compared to the baseline scenario.
• The most significant price changes are observed for Sugar Beet, with variations between 5% and 100%.
• Winter Wheat has the lowest price variation, while Sugar Beet has the highest.
• Serbia and BIH (Rest of SRB) are the most vulnerable to price increases.

7. Country-Specific Yield Changes in 2070

• Albania: Negative yield changes for all crops, with Sunflower most affected.
• Croatia: Sugar Beet production is predicted to decrease by 5%, with other crops showing moderate losses.
• Serbia and BIH: Grape, Tomato, and Potato yields are expected to decline by around 6%, with higher losses for Sugar Beet and Sunflower.
• Slovenia: Slight yield changes, with a small loss of around -0.2% for most crops.

8. Population Trends

• Population growth in the SRB is projected to decrease slightly over the period 2010–2070.
• Albania and Macedonia are expected to grow by around 3%, while Bosnia and Herzegovina, Serbia, and Croatia are projected to experience minimal or no growth.

9. Sector and Region Classification

• The GTAP dataset is used with 57 sectors grouped into 15 categories, including agriculture, forestry, electricity, and transport.
• Countries are classified as either individual (Albania, Croatia, Slovenia) or as Rest of SRB (Bosnia and Herzegovina, Macedonia, Serbia).

Conclusion

The study highlights the varied economic impacts of climate change across the Sava River Basin, emphasizing the need for targeted adaptation strategies. The integration of climate models with economic analysis provides a robust framework for understanding how changes in water resources affect agricultural production, market prices, and overall economic performance. The findings suggest that while some crops and countries may benefit from climate change, the majority face challenges that could reduce yields and increase prices, affecting consumer welfare and trade dynamics.