Prediction device
The integrated forecasting device improves economic forecasting by incorporating climate data to correct and constrain sector-specific forecasts, addressing the limitations of existing methods and enhancing accuracy under climate change scenarios.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- NT T INC
- Filing Date
- 2024-12-16
- Publication Date
- 2026-06-25
Smart Images
Figure JP2024044447_25062026_PF_FP_ABST
Abstract
Description
Prediction device
[0001] This disclosure relates to a prediction device.
[0002] There is a need for technologies that can predict future economies at the national and regional levels. In particular, there is a need for technologies that can predict future economies while taking into account the impact of climate change.
[0003] When forecasting the future economy, regardless of the method described later, it is generally common to create scenarios that assume the future state of society and rising temperatures, and then forecast the economy 50 to 200 years into the future based on those scenarios.
[0004] Specifically, there are two approaches: the top-down approach described in Non-Patent Documents 1 to 3, and the bottom-up approach described in Non-Patent Documents 4 to 7.
[0005] In a top-down approach, the relationship between per capita GDP (Gross Domestic Product) growth rates for each year in the past and climate data (e.g., average annual temperature, annual precipitation, magnitude of annual temperature fluctuations, number of days with extreme heat, number of days with extreme rainfall) is statistically analyzed to determine the relationship between per capita GDP and climate.
[0006] In the bottom-up approach, the impact of climate is estimated for each sector, such as crop yield, using historical data and models, and the combined impact of all sectors is used as the impact on GDP.
[0007] Marshall Burke, 2nd author, “Global non-linear effect of temperature on economic production”, Nature, October 21, 2015, [online], [searchable December 4, 2015], <URL: https: / / www.nature.com / articles / nature15725> Paul Waidelich, 4th author, “Climate damage projections beyond annual temperature”, Nature, April 17, 2024, [online], [searchable December 4, 2015], <URL: https: / / www.nature.com / articles / s41558-024-01990-8> Matthias Kalkuhl, 1st author, “The impact of climate conditions on economic production. Evidence from a global panel of regions”, Journal of Environmental Economics and Management, September 2020, [online], [searchable December 4, 2006], <URL: https: / / www.sciencedirect.com / science / article / pii / S0095069620300838> Takahiro Oda, 22 others, "Total economic costs of climate change at different discount rates for market and non-market values", ENVIRONMENTAL RESEARCH, 2023, [searchable December 4, 2006], <URL: https: / / iopscience.iop.org / article / 10.1088 / 1748-9326 / accdee> William D. Nordhaus, 1 others, "Warming the World Economic Models of Global Warming", 2000, [searchable December 4, 2006], <URL: https: / / eml.berkeley.>edu / ~saez / course131 / Warm-World00.pdf>Rob Dellink and others, “The Sectoral and Regional Economic Consequences of Climate Change to 2060”, SPRINGER NATURE, December 18, 2017, [Retrieved December 4, 2020], <URL: https: / / link.springer.com / article / 10.1007 / s10640-017-0197-5>Tom Kompas and others, “The Effects of Climate Change on GDP by Country and the Global Economic Gains From Complying With the Paris Climate Accord”, AGU, July 13, 2018, [Retrieved December 4, 2020], <URL: https: / / agupubs.onlinelibrary.wiley.com / doi / full / 10.1029 / 2018EF000922>.
[0008] However, the top-down approach only analyzes the relationship between GDP and climate, and therefore cannot adequately explain the economic impact of climate change. Because it does not explain the mechanisms, the basis for predictions regarding unprecedented conditions is insufficient. Furthermore, the economic predictions were limited to GDP.
[0009] In the bottom-up approach, climate impacts are estimated sector by sector, making it difficult to cover all sectors relevant to the real global economy, resulting in omissions and gaps. Consequently, forecasts of the impact on GDP were underestimated. Furthermore, there were errors in GDP forecasts for each sector, and aggregating the impact on GDP from each sector exacerbated the overall GDP forecast error.
[0010] This disclosure is made in view of the circumstances described above, and its purpose is to provide a technology that can improve economic forecasting techniques that take into account the impacts of climate change.
[0011] A forecasting device according to one aspect of the present disclosure includes: a climate forecasting unit that calculates climate forecast values based on a scenario; a top-down economic forecasting unit that calculates economic forecast values based on the scenario and corrects the economic forecast values with the climate forecast values using a top-down approach to calculate economic forecast values including top-down climate change effects; and a bottom-up economic forecasting unit that corrects sector values with the climate forecast values, inputs the corrected sector values into a general equilibrium model that deals with the economic equilibrium between sectors, uses the economic forecast values including top-down climate change effects as constraints on the general equilibrium model, and obtains economic forecast values including bottom-up climate change effects from the general equilibrium model.
[0012] This disclosure suggests that it is possible to improve economic forecasting techniques that take into account the impacts of climate change.
[0013] Figure 1 shows an example of the functional block configuration of the prediction device. Figure 2 shows an example of the operation of the prediction device. Figure 3 shows an example of the hardware configuration of the prediction device.
[0014] Embodiments of this disclosure will be described below with reference to the drawings. In the drawings, the same parts are denoted by the same reference numerals and their descriptions are omitted.
[0015] [Summary of this Disclosure] This disclosure combines economic forecasts that consider the impacts of climate change using a top-down approach with economic forecasts that consider the impacts of climate change using a bottom-up approach. In particular, the economic forecast results from the top-down approach are used as constraints for the economic forecast from the bottom-up approach. This solves the problems of both the top-down and bottom-up approaches.
[0016] [Configuration of the prediction device] Figure 1 is a diagram showing an example of the functional block configuration of the prediction device 1 according to this embodiment.
[0017] Prediction device 1 is a device that predicts macroeconomic factors (for example, GDP, energy, food, water demand, manufacturing, construction, services, land use patterns, and prices) that take into account the effects of climate change.
[0018] The forecasting device 1 comprises a climate forecasting unit 11, a top-down economic forecasting unit 12, a bottom-up economic forecasting unit 13, and a data storage unit 14.
[0019] The climate prediction unit 11 has the function of calculating climate prediction values based on predetermined scenarios. A scenario is an assumption about the future state of society, temperature increases, etc. Examples include the SSP scenario, the PCR scenario, and the "business as usual" scenario (business as usual scenario).
[0020] The top-down economic forecasting unit 12 has a function to calculate an economic forecast that includes the effects of top-down climate change using the predetermined scenario and the climate forecast values.
[0021] Specifically, the top-down economic forecasting unit 12 calculates economic forecast values (for example, GDP forecast values) based on the predetermined scenario, and corrects these economic forecast values with the climate forecast values using a top-down approach.
[0022] The bottom-up economic forecasting unit 13 has the function of calculating a bottom-up economic forecast including the effects of climate change using the predetermined scenario, the climate forecast, and the "top-down economic forecast including the effects of climate change," and further using a general equilibrium model that deals with the economic equilibrium between sectors.
[0023] Specifically, the bottom-up economic forecasting unit 13 corrects the sector values input (set) into the general equilibrium model with the climate forecast values, inputs the corrected sector values into the general equilibrium model, and obtains a bottom-up economic forecast including the effects of climate change from the general equilibrium model.
[0024] At this time, the bottom-up economic forecasting unit 13 inputs (sets) the above-mentioned "top-down economic forecast including the effects of climate change" as a constraint condition for the general equilibrium model into the general equilibrium model.
[0025] The data storage unit 14 has the function of storing economic forecasts, including the effects of climate change, calculated by the bottom-up economic forecasting unit 13. In other words, the data storage unit 14 stores future macroeconomic information and information on the scale of future economic activity. If the general equilibrium model outputs economic forecasts for each sector, the sector-specific economic forecasts are stored.
[0026] In this embodiment, a top-down economic forecast is used as a constraint to forecast a bottom-up economy based on sector values (needs). In other words, the economic forecast results from the top-down approach and the economic forecast results from the bottom-up approach are combined. Therefore, the challenges of both the top-down and bottom-up approaches can be solved, and economic forecasting technology that takes the impact of climate change into consideration can be improved.
[0027] [Operation of the prediction device] Figure 2 shows an example of the operation of the prediction device 1.
[0028] Step S1; The top-down economic forecasting unit 12 calculates a forecast value for future per capita GDP based on the SSP scenario.
[0029] The SSP scenario is a shared socioeconomic path that assumes future socioeconomic development trends based on technological and energy advancements. Generally, widely known SSP scenarios consider factors influencing GDP, such as socioeconomics, demographics, technology, lifestyle, policies, and institutions, but do not consider the impact of climate change. The top-down economic forecasting unit 12 calculates a projected value for future per capita GDP that does not include the impact of climate change.
[0030] Step S2; The climate prediction unit 11 calculates predicted values for the future climate based on the above SSP scenario.
[0031] For example, the climate prediction unit 11 uses weather forecast data provided by CMIP, etc., to calculate predicted future climate values (e.g., annual average temperature and annual precipitation at the national or regional level) based on the future technological advancements assumed in the above SSP scenario.
[0032] CMIP is a project (Coupled Model Intercomparison Project) of the World Climate Research Programme that provides climate predictions to understand past, present, and future climate change.
[0033] Step S3; The top-down economic prediction unit 12 corrects the predicted value of future GDP per capita that does not include the impact of climate change calculated in Step S1 with the predicted value of future climate calculated in Step S2 using a top-down impact prediction technique.
[0034] For the top-down impact prediction technique, for example, the technique of Non-Patent Document 2 may be used. Specifically, the respective formulas S11, S12, S15, and S17 described in "Appendix C" of Non-Patent Document 2 may be sequentially calculated. Hereinafter, the calculation example will be described. Note that S11, S12, S15, and S17 correspond to Formulas (1) to (4) described later.
[0035] (Step S3-1) First, the top-down economic prediction unit 12 substitutes the predicted value of future climate (here, temperature) calculated in Step S2 into Formula (1) to calculate the annual average temperature h Ｔ ｉ，ｔ in region i in year t.
[0036]
[0037] T ｉ，ｔ represents the annual average temperature in region i in year t. β Ｔ represents the coefficient of temperature variation of the annual average temperature T. k ０ represents the first year among the 41 years from 1980 to 2010.
[0038] (Step S3-2) Next, the top-down economic prediction unit 12 assumes that the predicted value of GDP calculated in Step S1 includes the impact of temperature over the 41 years, and uses the average value of temperature over the assumed 41 years as a baseline.
[0039] Subsequently, as shown in Formula (2), the top-down economic prediction unit 12 uses the annual average temperature h calculated in Formula (1) Ｔ ｉ，ｔBy subtracting the baseline from this, the GDP correction amount δ in logarithmic difference form is obtained. Ｔ ｉ，ｔ，ｌｏｇ is calculated.
[0040]
[0041] (Step S3-3) Next, the top-down economic prediction unit 12 substitutes the calculation result calculated by Equation (2) into Equation (3) and solves it to calculate the GDP correction amount δ Ｔ ｉ，ｔ is calculated.
[0042]
[0043] (Step S3-4) Finally, the top-down economic prediction unit 12 substitutes the calculation result calculated by Equation (3) into Equation (4) and solves it to calculate the predicted value GDP of GDP corrected by the influence of temperature fluctuation Ｔ ｉ，ｔ is calculated.
[0044]
[0045] By Step S3, the predicted value of GDP including the influence of top-down climate change is calculated.
[0046] Step S4; Finally, the bottom-up economic prediction unit 13 uses the above SSP scenario and a general equilibrium model that deals with economic equilibrium between sectors to calculate the scale of future economic activities in a bottom-up manner. That is, the predicted value of the future economy including the influence of bottom-up climate change is calculated.
[0047] At this time, the bottom-up economic prediction unit 13 corrects the set value for each sector (for example, production efficiency, demand quantity, supply quantity) input to the general equilibrium model with the predicted value of the future climate (temperature) calculated in Step S2.
[0048] Further, the bottom-up economic prediction unit 13 inputs the predicted value of GDP including the influence of top-down climate change calculated in Step S3 into the general equilibrium model as a constraint condition of the general equilibrium model.
[0049] In other words, the general equilibrium model calculates bottom-up forecasts of the future economy based on sector values that include the effects of climate change, but in doing so (when finding the equilibrium state), it uses top-down forecasts of GDP that include the effects of climate change as constraints.
[0050] I will now explain some specific examples.
[0051] For general equilibrium models, one could use, for example, a GCAM. GCAM stands for Global Change Analysis Model, a market equilibrium model with a global scope. For example, it deals with all aspects of economic activity, including GDP, energy, food, water demand, manufacturing, construction, services, land use patterns, prices, etc.
[0052] (Step S4-1) The bottom-up economic forecasting unit 13 corrects the predicted value of future agricultural productivity based on the research results on the impact of temperature fluctuations on agricultural productivity, and sets the corrected agricultural productivity in the input field (agricultural productivity) of the agricultural productivity sector in GCAM.
[0053] (Step S4-2) The bottom-up economic forecasting unit 13 corrects the demand for heating and cooling energy (number of days when heating and cooling are needed) based on the demand data for heating and cooling energy due to temperature fluctuations, and sets the corrected demand for heating and cooling energy in the input field (Heating / cooling degree days) of the heating and cooling energy demand sector in GCAM.
[0054] (Step S4-3) Subsequently, the bottom-up economic forecasting unit 13 inputs the top-down GDP forecast values, including the effects of climate change, calculated in step S3, into the GCAM as constraints, and has the GCAM run a simulation to forecast the future macroeconomy, including the effects of climate change.
[0055] GCAM (Global Computational Amplification) seeks a balance between agricultural productivity, heating and cooling energy, and other factors, and outputs macroeconomic information based on that balance. However, its output is constrained by the fact that it is a GDP forecast that includes the effects of top-down climate change.
[0056] [Effects] According to this embodiment, the climate forecasting unit 11 predicts climate based on the SSP scenario, the top-down economic forecasting unit 12 calculates a predicted GDP based on the SSP scenario, and corrects the predicted GDP with the predicted climate (temperature) using a top-down approach to calculate a predicted GDP that includes the effects of top-down climate change. The bottom-up economic forecasting unit 13 corrects sector values with the predicted climate, inputs the corrected sector values into a general equilibrium model that deals with the economic equilibrium between sectors, uses the predicted GDP that includes the effects of top-down climate change as a constraint on the general equilibrium model, and obtains a predicted economy that includes the effects of bottom-up climate change from the general equilibrium model. Thus, this provides a technology that can improve economic forecasting technology that takes into account the effects of climate change.
[0057] In other words, in this embodiment, a top-down GDP forecast is used as a constraint to forecast a bottom-up economy based on sector values (needs). Because the economy is forecasted using a top-down approach, underestimation due to omissions of sectors can be eliminated, and the accumulation of errors when aggregating the impact of each sector can suppress the expansion of errors in the GDP forecast. Because the economy is forecasted using a bottom-up approach, forecasts based on the mechanisms of economic impact become possible, and a certain degree of basis can be given to forecasts for unprecedented conditions.
[0058] [Other] This disclosure is not limited to the embodiments described above. This disclosure can be modified in numerous ways within the scope of the gist of this disclosure.
[0059] The prediction device 1 of this embodiment described above can be realized using a general-purpose computer system, for example, as shown in Figure 3, which includes a CPU 901, a memory 902, a storage 903, a communication device 904, an input device 905, and an output device 906. The memory 902 and the storage 903 are storage devices. In this computer system, each function of the prediction device 1 is realized when the CPU 901 executes a predetermined program loaded onto the memory 902.
[0060] The prediction device 1 may be implemented on a single computer. The prediction device 1 may be implemented on multiple computers. The prediction device 1 may be a virtual machine implemented on a computer.
[0061] The program for prediction device 1 can be stored on a computer-readable recording medium such as an HDD, SSD, USB memory, CD, or DVD. A computer-readable recording medium is, for example, a non-transitory recording medium. The program for prediction device 1 can also be distributed via a communication network.
[0062] 1 Prediction device 11 Climate prediction unit 12 Top-down economic forecasting unit 13 Bottom-up economic forecasting unit 14 Data storage unit 901 CPU 902 Memory 903 Storage 904 Communication device 905 Input device 906 Output device
Claims
1. A forecasting device comprising: a climate forecasting unit that calculates climate forecast values based on a scenario; a top-down economic forecasting unit that calculates economic forecast values based on the scenario and corrects the economic forecast values with the climate forecast values using a top-down approach to calculate economic forecast values including the effects of top-down climate change; and a bottom-up economic forecasting unit that corrects sector values with the climate forecast values, inputs the corrected sector values into a general equilibrium model that deals with the economic equilibrium between sectors, uses the economic forecast values including the effects of top-down climate change as constraints on the general equilibrium model, and obtains economic forecast values including the effects of bottom-up climate change from the general equilibrium model.
2. The forecasting device according to claim 1, wherein the forecast value of the economy, including the top-down impact of climate change, is a forecast value of GDP.