In the Paris Agreement, Turkey pledged to reduce greenhouse gas (GHG) emissions by 21% by 2030 relative to business-as-usual (BAU). However, Turkey relies heavily on imported energy and fossil-intensive power generation. And despite significant wind and solar energy potential, only 5.1% of its total power is generated by wind and solar installations. Finally, although two nuclear power stations are planned, no nuclear capacity currently exists.

This study is based on an expectation that to fulfill its Paris Agreement pledge, Turkey will likely need to reduce its reliance on fossil-based energy and make additional investments in low-carbon energy sources—moves that may impact the nation’s GDP, electricity generation profiles and resulting carbon prices. To fully assess these impacts, the researchers develop a computable general equilibrium (CGE) model of the Turkish economy that combines macroeconomic representation of non-electric sectors with a detailed representation of the electricity sector. They analyze several scenarios to assess the impact of an emission trading scheme in Turkey: one including the planned nuclear development and renewable subsidy scheme (BAU), the other in which no nuclear technology is allowed (NoN).

The assessment shows that in 2030, without an emissions trading policy, the primary energy mix will consist mainly of oil, natural gas and coal. Under an emission trading scheme, however, coal-fired power generation vanishes by 2030 in both BAU and NoN due to the high cost of carbon. With nuclear (BAU), GHG emissions are 3.1% lower than NoN due to the resulting energy mix, allowing for a lower carbon price ($50/tCO₂ in BAU compared to $70/tCO₂ in NoN). These results suggest that fulfillment of Turkey’s Paris Agreement pledge may be possible at a modest economic cost of about 0.8–1% of GDP by 2030.

Today different regions must meet growing demand for land—most notably for food and bioenergy crops—amid changes in the local availability of fresh water. One approach is to boost crop yields through improvements in irrigation technology, but its implementation would require actionable estimates on the current scope of irrigated land and how much additional land can be irrigated, in what regions, and at what cost. To that end, this study develops a framework to more accurately represent the value of irrigated crop production and the potential of irrigated land areas to expand within economy-wide, applied general equilibrium (AGE) models.

The researchers compute the value of production on irrigated and rainfed cropland at an approximately 10-square kilometer grid-cell level as well as for the 140 regions and eight crop sectors in Version 9 of the Global Trade Analysis Project (GTAP) Data Base. For each crop category, they estimate and compare the dollar-value of irrigated and rainfed crop production using estimates of production quantities and prices. To represent the potential of irrigated land areas to expand, the researchers use irrigable land supply curves for 126 water regions globally, based on water availability and the costs of irrigation infrastructure. These curves enable regions to adapt to changes in water resources and agriculture demand through irrigation technology and crop production intensification.

The researchers’ new framework allows for more rigorous integrated assessments of regional and global impacts of water availability on land use, energy production and economic activity. They make this user-customizable framework available to enable other researchers to make integrated assessments of the current production value and expansion potential of irrigated land.

The 195 signatories of the Paris Agreement on climate change have committed to reduce greenhouse gas (GHG) emissions so as to keep the global temperature rise from preindustrial levels to well below two degrees Celsius (2°C). While much of this international effort has focused on the economy’s two largest-emitting sectors, electricity and transportation, achieving net-zero emissions will require emissions reductions in all sectors of the economy. That includes construction.

Among the most difficult emissions to reduce are cement and steel, which are primarily used as building materials. One potential solution is to substitute for these materials with engineered wood products, which are less GHG-intensive and have seen rapid growth in the construction industry in recent decades. This study evaluates the economy-wide impacts of replacing carbon-intensive construction inputs, such as steel and cement, with lumber products in the U.S. under an emissions constraint. It’s one of the few studies to examine the emission and economic impacts of these products under a climate policy.

Drawing upon their U.S. economy database, the researchers determined that the carbon dioxide (CO₂) intensity of lumber production is about 20 percent less than that of fabricated metal products, under 50 percent that of iron and steel, and under 25 percent that of cement. They found that the ability to substitute lumber-based building materials increases production from the lumber and forestry sectors and decreases production from carbon-intensive sectors such as cement. Under a carbon cap-and-trade policy, the ability to substitute lumber products lowers the carbon price and the GDP cost of meeting the carbon cap, with more overall emissions abatement in the construction industry.