Life process tracking and future risk estimation method and equipment for migrating heat waves between sea and land

Abstract

The invention relates to the field of carbon neutralization, and discloses a sea-land migration heat wave life process tracking and future risk estimation method and device, and the method comprises the steps: downloading data; sea source type landing heat wave and terrestrial source type landing heat wave events are identified; quantifying space-time attribute characteristics of the sea source type landing heat waves and the terrestrial source type landing heat waves; detecting the influence of different human activities on the sea source type landing heat waves and the terrestrial source type landing heat waves; a physical mechanism of a weather scale and an inter-year scale of sea source type landing heat wave and terrestrial source type sea entering heat wave migration and landing or sea entering; estimating the risk of sea source type landing heat waves and terrestrial source type landing heat waves in a future high emission scene; according to the method, the response situation under the artificial climate change is analyzed, the physical mechanism of landing and entering the sea is clarified, the understanding of the life cycle process of the two types of sea-land migrated heat waves is deepened, and a scientific basis is provided for coping with natural challenges brought by the two types of sea-land migrated heat waves under the climate change.

Description

Technical Field

[0001] The present invention relates to the field of carbon neutrality, and in particular to a method and device for tracking the life process of migratory heat waves between sea and land and predicting future risks. Background Art

[0002] Heat waves are one of the most serious meteorological disasters in the world, causing incalculable casualties and socioeconomic losses every year. As human activities further intensify global warming, the threat posed by heat waves is increasing day by day. From static perspectives such as grid and station scales, a large number of studies have shown that heat waves will become more frequent, persistent, widespread and severe under global warming. In recent years, three-dimensional space-time tracking methods have also proved from a dynamic perspective that human society will face an increasing threat of heat waves. However, the academic community currently only studies marine heat waves and land heat waves as isolated individuals, causing scientific researchers to seriously ignore the integrity of heat waves. As one of the factors driving the migration of heat waves, thermal advection between sea and land plays a vital role in the migration of heat waves. For example, the North American heat wave in 2021 originated in the northwest Pacific and gradually developed to the North American continent under the action of thermal advection. However, the role of climate change caused by human activities in marine-sourced landfall heat waves and land-sourced sea-entry heat waves has not attracted the attention of the academic community, and the physical mechanism of the two types of sea-land migration heat waves is still in urgent need of analysis. Summary of the invention

[0003] The purpose of the present invention is to propose a method and device for tracking the life cycle of sea-land migration heat waves and predicting future risks, so as to solve the technical problem that the physical mechanisms of sea-source landfalling heat waves and land-source sea-entering heat waves in the prior art are still understudied.

[0004] The present invention provides a method for tracking the life process of a heat wave between sea and land and predicting future risks, comprising the following steps:

[0005] Step S1: data download;

[0006] Step S2: Identify marine-sourced landfalling heat waves and land-sourced sea-entering heat wave events; according to the data downloaded in step S1, threshold discrimination is performed on the warm season daily average temperature based on the dynamic climate threshold method, and grid points with daily average temperatures exceeding the 90th percentile are defined as high-temperature grid points. The Lagrangian three-dimensional space-time tracking method is used to obtain the three-dimensional space-time cube structure of the heat wave, and it is divided into marine heat waves, land heat waves, marine-sourced landfalling heat waves, and land-sourced sea-entering heat waves according to the heat wave generation area and migration process.

[0007] Step S3: quantify the spatiotemporal attribute characteristics of sea-sourced landfalling heat waves and land-sourced sea-entering heat waves; calculate the spatiotemporal attribute characteristics of heat wave events based on the spatiotemporal cubes of ocean heat waves, land heat waves, sea-sourced landfalling heat waves and land-sourced sea-entering heat waves obtained in step S2, and statistically divide the directions of heat wave migration in the region;

[0008] Step S4: Detect the impact of different human activities on sea-sourced landfall heat waves and land-sourced sea-entering heat waves; based on the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events obtained in step S3, calculate the relative changes of the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves under three different external forcing scenarios, namely, human forcing, greenhouse gas forcing, and human aerosol forcing, compared with the average values ​​of the historical period, and analyze the impact of different types of human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves;

[0009] Step S5: The weather scale and decadal scale physical mechanism of the migration and landing or entering the sea of ​​the sea-sourced landfall heat wave and the land-sourced sea-entering heat wave; according to the two types of sea-land migration heat wave events obtained in step S3, the circulation field during the heat wave period is constructed according to the meteorological elements and factors, and the weather scale evolution process and physical mechanism of the migration and landing or entering the sea of ​​the two types of sea-land migration heat waves are analyzed; the decadal scale changes of the meteorological elements and factors of the earth system physical factors driving the migration of the two types of sea-land migration heat waves are analyzed to clarify the decadal physical mechanism driving the migration of heat waves;

[0010] Step S6: Estimate the risks of sea-sourced landfalling heat waves and land-sourced heat waves entering the sea under future high emission scenarios; combine the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves obtained in step S3 to make future predictions of the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events, explore the signal-to-noise ratio of the characteristics of the two types of sea-land migration heat wave events under high emission scenarios in the future, and make risk estimates for sea-sourced landfalling heat waves and land-sourced heat waves entering the sea on a global scale.

[0011] A storage medium stores instructions and data for realizing a method for tracking the life process of heat waves migrating between sea and land and estimating future risks.

[0012] A device for tracking the life process of heat waves during migration between sea and land and estimating future risks comprises: a processor and the storage medium; the processor loads and executes instructions and data in the storage medium to implement a method for tracking the life process of heat waves during migration between sea and land and estimating future risks.

[0013] The beneficial effects provided by the present invention are:

[0014] (1) This invention innovatively proposes a method for identifying sea-sourced landfall heat waves and land-sourced sea-entry heat waves, revealing the migration process of heat waves between land and sea. This invention identifies two types of heat waves that migrate between land and sea, clarifies the changes and impacts of the two types of heat waves that migrate between land and sea in spatial and temporal dimensions, and provides a scientific basis for responding to the natural challenges brought about by the two types of heat waves that migrate between land and sea.

[0015] (2) This paper quantifies the spatiotemporal properties of different anthropogenic forcings on the effects of sea-originated landfall heat waves and land-originated sea-entering heat waves, and evaluates the impacts of different anthropogenic forcings on the two types of land-sea migration heat waves, providing new theoretical support for governments and international cooperation organizations to make decisions and recommendations on adapting to and mitigating the effects of climate change on the two types of land-sea migration heat waves.

[0016] (3) The present invention analyzes the atmospheric circulation conditions for the landing or entry of sea-originated heat waves and land-originated heat waves into the sea, and clarifies the migration paths of the two types of sea-land migration heat waves in historical periods, providing groundbreaking theoretical support for the prediction of the two types of sea-land migration heat waves. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic flow chart of the method of the present invention;

[0018] Figure 2 It is the overlapping area threshold sensitivity experiment of the migrating heat wave between sea and land and the temporal variation trend of the temperature threshold;

[0019] Figure 3 It is a typical example of a sea-originated landfall heat wave;

[0020] Figure 4 It is a typical case of land-based heat waves entering the sea;

[0021] Figure 5 It is the historical spatiotemporal attribute characteristics of the four types of heat waves;

[0022] Figure 6 It is a diagram of the process of generation, migration, landing or entering the sea of ​​two types of heat waves migrating between land and sea;

[0023] Figure 7 is the relative change in the frequency of heat waves migrating between land and sea under two different historical forcings;

[0024] Figure 8 It is a diagram of the physical mechanism of two types of heat waves migrating between land and sea;

[0025] Fig. 9 is the relative change in the frequency of the two types of land-sea migration heat waves under future high emission scenarios compared with the historical period;

[0026] Fig.10 is the impact of different anthropogenic forcings on the risk ratio of the frequency of two types of land-sea migration heat waves under future high emission scenarios;

[0027] Fig.11 It is a working schematic diagram of the hardware device of the present invention. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0029] Before formally describing the present invention, the scheme of the present invention is first generally described for easy understanding.

[0030] Please refer to Figure 1 , Figure 1 It is a schematic diagram of the process of the present invention.

[0031] The present invention provides a method for tracking the life process of a heat wave during migration between sea and land and estimating future risks, comprising the following steps:

[0032] Step S1: data download;

[0033] As a preferred embodiment, the present invention collects 2m temperature, 10m, 850hPa and 500hPa longitudinal and latitudinal wind speeds, 850hPa air pressure and 500hPa geopotential height data from the Sixth International Coupled Model Intercomparison Project (CMIP6), the Common Earth System Model Large Sample Collection (CESM-LENS), and the European Center for Medium-Range Weather Forecasts Fifth Generation Reanalysis Dataset (ERA5); collects 2m temperature data under natural forcing, greenhouse gas forcing and anthropogenic aerosol forcing from the Detection Attribution Model Intercomparison Project (DAM IP) in CM IP6 and 2m temperature data under greenhouse gas forcing and anthropogenic aerosol forcing from the Common Earth System Model Single Forcing Large Sample Collection (CESM1-Single Forcing); and collects mask files for global land areas and boundaries.

[0034] Step S2: Identify marine-sourced landfalling heat waves and land-sourced sea-entering heat wave events; according to the data downloaded in step S1, threshold discrimination is performed on the warm season daily average temperature based on the dynamic climate threshold method, and grid points with daily average temperatures exceeding the 90th percentile are defined as high-temperature grid points. The Lagrangian three-dimensional space-time tracking method is used to obtain the three-dimensional space-time cube structure of the heat wave, and it is divided into marine heat waves, land heat waves, marine-sourced landfalling heat waves, and land-sourced sea-entering heat waves according to the heat wave generation area and migration process.

[0035] It should be noted that the above-mentioned warm season specifically refers to the warm season in the northern hemisphere: May to September, and the warm season in the southern hemisphere: November to March of the following year;

[0036] Step S2 is specifically as follows:

[0037] S21: Based on 2m temperature data from historical model experiments, natural forcing experiments, greenhouse gas forcing experiments, anthropogenic aerosol forcing experiments and shared socioeconomic pathway high emission scenario simulation experiments, the dynamic climate threshold method with a 30-year window period is used to quantify the annual warm season heat wave temperature threshold;

[0038] S22: The Lagrangian three-dimensional space-time tracking method identifies global heat wave events in the space-time scale, as follows: if the grid temperature is greater than the temperature threshold obtained in step S21, the grid point is defined as a high temperature grid point; adjacent high temperature grid points in the same time dimension are merged into spatially continuous high temperature patches in the two-dimensional space level; if the overlapping area of ​​the high temperature patches in the continuous time steps is greater than the preset area, and this continuous time step is at least greater than the preset number of days, they are merged into a three-dimensional heat wave event; the life cycle of the three-dimensional heat wave event is at least greater than the preset number of days, and the daily minimum area must be greater than the preset area;

[0039] As an embodiment, in step S2, the 2m temperature data of each mode of the high emission scenario of the historical period model test, the natural forcing test, the greenhouse gas forcing experiment, the anthropogenic aerosol forcing experiment and the shared socioeconomic pathway simulation test are used to perform threshold judgment on the warm season daily average temperature based on the dynamic climate threshold method, and the grid points with daily average temperature exceeding the 90th percentile are defined as high temperature grid points. The Lagrangian three-dimensional space-time tracking method is used to obtain the heat wave three-dimensional space-time cube. If the grid temperature is greater than the temperature threshold obtained in step S21, the grid point is defined as a high temperature grid point; adjacent high temperature grid points in the same time dimension are merged into continuous high temperature patches at the two-dimensional spatial level; if the overlapping area of ​​the high temperature patches in continuous time steps is greater than 100,000 km 2 , and the continuous time step is at least greater than 3 days, it is merged into a 3D heat wave event; the 3D heat wave event lasts at least 3 days, and the minimum daily area must be greater than 100,000 km 2 .

[0040] S23: Using the mask file data of the global land area and boundaries of step S1, set the minimum landing area threshold of the sea-originated landfall heat wave and the minimum sea entry area threshold of the land-originated sea-entering heat wave, and identify the three-dimensional heat wave events that originate from the ocean or land and then move to the land or ocean as sea-originated landfall heat wave events or land-originated sea-entering heat wave events, respectively.

[0041] As an example, according to the mask file of the global land area and boundaries in step S1, the minimum landing and sea entry areas are set, and three-dimensional heat wave events originating from the ocean or land, and whose landing or sea entry areas exceed the area threshold, are identified as sea-sourced landing heat waves or land-sourced sea entry heat wave events. In the present invention, the minimum landing area and the minimum overlapping area are both set to 100,000 km 2 .

[0042] Step S3: quantify the spatiotemporal attribute characteristics of sea-sourced landfalling heat waves and land-sourced sea-entering heat waves; calculate the spatiotemporal attribute characteristics of heat wave events based on the spatiotemporal cubes of ocean heat waves, land heat waves, sea-sourced landfalling heat waves and land-sourced sea-entering heat waves obtained in step S2, and statistically divide the directions of heat wave migration in the region;

[0043] Step S3 is specifically as follows:

[0044] The temporal, spatial and attribute characteristics of sea-originated landfalling heat waves and land-originated sea-entering heat waves are frequency and life cycle, area and intensity respectively; the frequency is the number of occurrences of the two types of sea-land migration heat wave events each year; the life cycle is the duration of the two types of sea-land migration heat wave events; the area is the affected area of ​​the two types of sea-land migration heat waves; the intensity is the sum of the product of the part of the grid temperature exceeding the threshold and the grid area during the heat wave period.

[0045] Step S4: Detect the impact of different human activities on sea-sourced landfall heat waves and land-sourced sea-entering heat waves; based on the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events obtained in step S3, calculate the relative changes of the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves under three different external forcing scenarios, namely, human forcing, greenhouse gas forcing, and human aerosol forcing, compared with the average values ​​of the historical period, and analyze the impact of different types of human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves;

[0046] Step S4 is specifically as follows:

[0047] The impact of different human activities on sea-originated landfall heat waves and land-originated sea-entering heat waves is detected. According to the time, space and attribute characteristics of the two types of sea-land migration heat wave events under three different external forcing scenarios of anthropogenic forcing, greenhouse gas forcing and anthropogenic aerosol forcing calculated in the specific steps of step S3, the relative changes are compared with the average values ​​of the historical period, so as to analyze and evaluate the impact of human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves.

[0048] As an embodiment, the impact of different human activities on sea-sourced landfall heat waves and land-sourced sea-entering heat waves is detected; according to the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events obtained in step S3, the changes under different external forcing scenarios compared with the average values ​​of the historical period are calculated, that is, the relative changes of the spatiotemporal attribute characteristics (I) of the two types of sea-land migration heat waves under the influence of human forcing, greenhouse gas forcing and human aerosol forcing compared with the historical period, so as to evaluate the impact of these human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves, which are specifically as follows:

[0049] Step S5: The weather scale and decadal scale physical mechanism of the migration and landing or entering the sea of ​​the sea-sourced landfall heat wave and the land-sourced sea-entering heat wave; according to the two types of sea-land migration heat wave events obtained in step S3, the circulation field during the heat wave period is constructed according to the meteorological elements and factors, and the weather scale evolution process and physical mechanism of the migration and landing or entering the sea of ​​the two types of sea-land migration heat waves are analyzed; the decadal scale changes of the meteorological elements and factors of the earth system physical factors driving the migration of the two types of sea-land migration heat waves are analyzed to clarify the decadal physical mechanism driving the migration of heat waves;

[0050] Step S5 is specifically as follows:

[0051] S51: Based on the above initial data set, the atmospheric circulation field during the heat wave is established to analyze the weather-scale physical mechanism during the migration, landing or entry into the sea of ​​the two types of heat wave events between land and sea. Among them, the atmospheric circulation field focuses on the distribution of high-pressure systems in the 850hPa and 500hPa pressure layers during the heat wave migration process and the wind field matching the high-pressure system; According to the initial data set, the interdecadal scale changes in meteorological factors and earth system physical factors that drive the movement of the two types of heat waves between land and sea are analyzed to clarify the interdecadal physical mechanism driving the movement of heat waves. Among them, the sea-source landfalling heat wave focuses on the driving of the latitudinal wind field to make the heat wave land, and the land-source sea-entering heat wave focuses on the difference in thermal properties between land and sea that drives the high temperature of land to transport heat to the ocean, causing the heat wave to enter the sea.

[0052] As an embodiment, according to the initial data set downloaded in step S1, the atmospheric circulation field during the heat wave is established to analyze the weather-scale physical mechanism of the two types of heat wave events migrating between land and sea, during the migration, landing or entering the sea, wherein the atmospheric circulation field mainly focuses on the distribution of the high-pressure systems of the 850hpa and 500hpa pressure layers during the heat wave migration process and the wind field matching the high-pressure system. Taking the Chinese region as an example of the sea-source landing heat wave, the heat wave events that landed in China between 1981 and 2020 were selected, and the atmospheric circulation situation two days before and after the landing and on the day of landing was taken as a reference to analyze the position of the westward extension of the 500hpa layer subtropical high pressure ridge of the northwest Pacific Ocean for the sea-source landing heat wave in China and the changes and movements of the high-pressure system over China at the 850hpa layer; taking the Australian region as an example of the land-source heat wave entering the sea, the atmospheric circulation situation two days before and after the sea and on the day of the sea entry was taken as a reference to analyze the distribution and movement of the anomaly center of the 500hpa layer potential height of the land-source heat wave entering the sea and the changes and movements of the high-pressure system over China at the 850hpa layer. Changes and movements; According to the initial data set, the interdecadal changes in meteorological factors and earth system physical factors that drive the movement of two types of sea-land migration heat waves are analyzed to clarify the interdecadal physical mechanism driving the movement of heat waves, and the historical period is divided into two sections, before (1981-2000) and after (2001-2020). The zonal winds of sea-originated landfall heat waves in the two periods are differentiated to explore the driving effect of zonal winds on sea-originated landfall heat waves; the changes in temperature thresholds during the two periods of land-originated sea-entering heat waves are differentiated at the same latitude to focus on the role of the difference in thermal properties between land and sea at the same latitude in driving the high temperature of land to transport heat to the ocean, causing the heat wave to enter the sea.

[0053] Step S6: Estimate the risks of sea-sourced landfalling heat waves and land-sourced heat waves entering the sea under future high emission scenarios; combine the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves obtained in step S3 to make future predictions of the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events, explore the signal-to-noise ratio of the characteristics of the two types of sea-land migration heat wave events under high emission scenarios in the future, and make risk estimates for sea-sourced landfalling heat waves and land-sourced heat waves entering the sea on a global scale.

[0054] Step S6 is specifically as follows:

[0055] Based on the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves, future predictions of the attribute characteristics of the two types of sea-land migration heat wave events are made, and the relative changes, risk ratios and signal-to-noise ratios of the two types of sea-land migration heat wave event characteristics under high emission scenarios in the future are explored to conduct risk assessment of the two types of sea-land migration heat waves on a global scale.

[0056] As an embodiment, the risks of sea-sourced landfalling heat waves and land-based heat waves entering the sea under future high emission scenarios are estimated; the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves obtained in step S3 are combined to make future predictions of the attribute characteristics of the two types of sea-land migration heat wave events, and the response of sea-land migration heat waves to human activities under global warming is evaluated based on the signal-to-noise ratio. The risk ratio of the two types of sea-land migration heat wave event characteristics under high emission scenarios in the future is explored to conduct risk assessment of sea-sourced landfalling heat waves and land-based heat waves entering the sea on a global scale.

[0057] The signal-to-noise ratio is calculated to evaluate the response of land-sea migration heat waves to human activities under global warming, as follows:

[0058]

[0059] Among them, the signal is the spatiotemporal characteristics of two types of sea-land migration heat waves in the future period (2061-2100) compared with the historical period (1981-2020). The relative change of SNR is the average of 8 models of CMIP6 and 40 ensembles of CESM-LENS. The noise is defined as the standard deviation σ(ΔI) between the modes or ensemble members of the relative change of the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves. If the absolute value of SNR is greater than 1, it means that anthropogenic climate change signals have been detected in CMIP6 or CESM-LENS. Conversely, if the absolute value of SNR is less than 1, no anthropogenic climate change signals have been detected.

[0060] In the above step S6, based on the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events in CMIP6 and CESM-LENS: frequency, life cycle, area and intensity, the future risk ratio of the characteristics of the two types of sea-land migration heat wave events under future high emission scenarios is quantified. The risk ratio is the change in the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves under different anthropogenic forcing under future high emission scenarios compared with the historical period, so as to estimate the severity of the two types of sea-land migration heat waves under future high emission scenarios. The formula is as follows:

[0061] In order to better explain the method of the present invention, as an implementation case, the present invention takes the global heat waves from 1981 to 2020 as an example and makes a more detailed description herein. The implementation case is suitable for analyzing the case of the present invention, but does not limit the scope of application of the present invention, and is still applicable to specific regions and other periods.

[0062] The implementation flow chart of the method for tracking the life process of heat waves between sea and land and estimating future risks of the method of the present invention is as follows: Figure 1 As shown, the specific steps are as follows:

[0063] (1) Collect test data;

[0064] In this implementation case, the 2m temperature, 10m, 850hPa and 500hPa meridian and zonal wind speed, 850hPa air pressure and 500hPa geopotential height data of the Sixth International Coupled Model Intercomparison Project (CMIP6), Common Earth System Model Large Sample Ensemble (CESM-LENS), and the European Centre for Medium-Range Weather Forecasts Fifth Generation Reanalysis Dataset (ERA5) are collected; the 2m temperature data under natural forcing, greenhouse gas forcing and anthropogenic aerosol forcing of the Detection Attribution Model Intercomparison Project (DAMIP) in CMIP6 and the 2m temperature data under greenhouse gas forcing and anthropogenic aerosol forcing of the Common Earth System Model Single Forcing Large Sample Ensemble (CESM1-Single Forcing) are collected; the mask files of global land areas and boundaries are collected; the time range of the above data is 1951-2100. Based on the climate data processing system CDO, bilinear interpolation is used for meteorological data to unify the spatial resolution between multiple models and large sample sets. The spatial resolution of the new data is 1.5°×1.5°, and the ERA5 reanalysis data are averaged daily in the time dimension to unify the temporal resolution.

[0065] (2) Identify sea-originated landfall heat waves and land-originated sea-entering heat waves;

[0066] This case takes the global region as an example, using the 2m temperature data of each model of the high emission scenario of the historical period model experiment, natural forcing experiment, greenhouse gas forcing experiment, anthropogenic aerosol forcing experiment and shared socioeconomic pathway simulation experiment, and using the dynamic climate threshold method to judge the threshold of the warm season daily average temperature. The grid points with daily average temperature exceeding the 90th percentile are marked as high temperature grid points, and the Lagrangian three-dimensional space-time tracking method is used to obtain the heat wave three-dimensional space-time cube; the adjacent high temperature grid points in the same time dimension are merged into continuous high temperature patches at the two-dimensional spatial level; if the overlapping area of ​​the high temperature patches in the continuous time step is greater than 100000km 2 , and the continuous time step is at least greater than 3 days, it is merged into a 3D heat wave event; the heat wave event lasts at least 3 days, and the minimum daily area must be greater than 100,000 km 2 .

[0067] According to the mask file of global land areas and boundaries, the minimum landing and sea entry areas are set, and heat wave events originating from the ocean or land, with the landing or sea entry areas exceeding the area threshold, are identified as sea-sourced landfall heat waves or land-sourced sea entry heat wave events. In this implementation case, the minimum landing area and the minimum overlap area are both set to 100,000 km 2 The minimum overlap area is obtained through sensitivity analysis, such as Figure 2 shown.

[0068] For specific typical cases, please refer to Figure 3 , Figure 4 ,in Figure 3 This is a case study of a heat wave that originated in the northwest Pacific in July 2003 and gradually migrated to China. Figure 4 This is the case of the heat wave that started in the desert region of western Australia in 2018 and eventually migrated into the sea in the South Pacific.

[0069] (3) Quantify the spatiotemporal characteristics of sea-originated landfall heat waves and land-originated sea-entering heat waves;

[0070] This case quantifies the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave three-dimensional events in the high-emission scenarios of historical climate simulation experiments, greenhouse gas experiments, natural forcing experiments, anthropogenic aerosol experiments, and shared socioeconomic pathway simulation experiments of 8 models from the Sixth International Coupled Model Intercomparison Project (CMIP6), 40 Common Earth System Model Large Sample Ensembles (CESM-LENS), and 20 Common Earth System Model Single Forcing Large Sample Ensembles (CESM1-Single Forcing). The time, space, and attribute characteristics of the two types of sea-land migration heat wave events are frequency, life cycle, area, and intensity; the frequency is the number of occurrences of the two types of sea-land migration heat waves each year; the life cycle is the duration of the two types of sea-land migration heat wave events; the area is the affected area of ​​the two types of sea-land migration heat waves; and the intensity is the sum of the product of the portion of the grid temperature exceeding the threshold and the grid area during the heat wave period. Figure 5 As shown in the data, from 1981 to 2020, there were 2133 and 1354 land-based heat waves and land-based heat waves respectively in the world. Compared with land heat waves and ocean heat waves, their life cycle (12.38 days, +237.9%; 11.84 days, +245.8%) and area (12.51×10 6 km 2 , +1015.2%; 8.16×10 6 km 2 , +359.3%), strength (35.64×10 6 K km 2 ·days, +1275.7%; 36.54×10 6 K km 2 ·days, +2005.9%) all indicate a more persistent, widespread and severe situation. Figure 5 , Figure 6, the latitudinal average of sea-originated landfall heat waves is bimodal, with high-value areas mostly distributed in tropical and southern hemisphere oceans. They mostly originate in the eastern Pacific and migrate eastward, while those originating in the western Pacific mostly move westward. Compared with land heat waves that mostly occur in central Europe, for central South America and South Africa, sea-originated landfall heat waves are more frequent in tropical regions. Land-originated sea heat waves mostly originate in central Europe, North Africa, South Africa, central South America and Western Australia. In the subtropical regions of the Northern Hemisphere, land-originated sea heat waves mostly move eastward, while there is no obvious pattern in the migration direction of other regions. Compared with marine heat waves that frequently occur in tropical and southern hemisphere oceans, land-originated sea heat waves mostly enter the sea in tropical and mid- and high-latitude regions of the Northern Hemisphere.

[0071] (4) Detect the impact of different human activities on sea-originated landfall heat waves and land-originated sea-entering heat waves;

[0072] This case is based on the spatial grid indicators of the spatiotemporal attribute characteristics of two types of sea-land migration heat waves. The relative changes of the spatiotemporal attribute characteristics (I) of the two types of sea-land migration heat waves in a specified period under the influence of three different external forcings relative to the historical average values, that is, the historical changes of the two types of sea-land migration heat waves under anthropogenic forcing, greenhouse gas forcing, and anthropogenic aerosol forcing. The formula has been stated above and will not be repeated here.

[0073] The relative changes are further calculated by using the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves under future high emission scenarios and historical periods, and the signal-to-noise ratio is calculated based on the relative changes to detect the impact of human activities on the two types of sea-land migration heat waves. The formula has been stated above and will not be repeated here.

[0074] Taking frequency as an example, Figure 7 As shown in the figure, compared with the CM IP6 multi-model ensemble average of the historical period (1981-2020), the frequency of sea-sourced landfall heat waves under anthropogenic forcing is increasing in about 82.2% of the regions, with an average increase of +30.9% in the global land area, while the frequency of land-based heat waves entering the sea is increasing in 81.1% of the global regions, with an average change of about +24.0% in the global ocean area. This large-scale and increasingly frequent trend is caused by the continuous greenhouse gas forcing in recent decades. Under the influence of greenhouse gas forcing, the two types of heat waves migrating between land and sea show a stronger increase trend, such as the frequency of sea-sourced landfall heat waves in land areas increases by about +39.3%, while the frequency of land-based heat waves entering the sea increases by +33.7%. In other words, anthropogenic aerosol forcing offsets part of the effect of greenhouse gas forcing, which is also sufficiently confirmed by the spatial frequency distribution of the two types of heat waves migrating between land and sea.

[0075] (5) Analyze the physical mechanisms of landfall and sea entry of sea-originated heat waves and land-originated heat waves;

[0076] According to the above atmospheric environmental variable data, the atmospheric circulation field during the sea-originated landfalling heat wave and the land-originated sea-entering heat wave events is constructed, the atmospheric circulation conditions for the two types of sea-land migration heat waves on the meteorological scale of landing and entering the sea are analyzed, and the meteorological elements and earth system physical factors that drive the landing and entering the sea of ​​the two types of sea-land migration heat waves on the interdecadal scale are explored; on the meteorological scale, because heat waves are closely related to high-pressure systems, the atmospheric circulation physical model uses 850hPa air pressure and 500hPa potential height as the main indicators for quantifying high-pressure systems, and uses the wind field of the same pressure layer as an auxiliary reference.

[0077] Taking China as an example, the 5880-potential-meter contour line is mainly identified to analyze the impact of the subtropical high pressure ridgeline in the northwest Pacific on the sea-sourced landfall heat waves. Figure 8 As shown in the figure, two days before the northwest Pacific heat wave migrated to East Asia, the 500hpa geopotential height field showed that the northwest Pacific subtropical high pressure ridge extended westward to the coastal areas of China, and it guided the low-level warm and humid air flow in the high-temperature area of ​​the Pacific to the East Asian region, driving the northwest Pacific heat wave to move to the coastal areas of East Asia. The 850hpa layer high pressure center stretched across China. The high pressure system controlled the sinking air flow in the region, which directly led to adiabatic warming, and indirectly reduced the cloud cover and then radiated warming, creating favorable conditions for the heat wave to land. On the day of the heat wave landing, the upper layer was still controlled by the northwest Pacific subtropical high pressure. A high pressure center of 5,900 geopotential meters had formed over the Kuroshio region, and the 850hpa layer high pressure system was further strengthened. In the following two days, the high pressure center continued to move westward, and the circulation situation of the high pressure system intensified. Most parts of China were hit by high temperature heat waves.

[0078] Taking Australia as an example, the influence of the movement of the high pressure system in the 850hpa pressure layer on the land-based heat waves entering the sea is mainly identified. Figure 8 As shown in the figure, the Rossby wave train that started in the Indian Ocean propagated eastward and stimulated the high pressure system in Australia. Two days before the Australian heat wave entered the sea, the continental region was mainly affected by the high pressure system and subtropical high pressure at the 850hpa layer, and the 500hpa pressure dipole evolved in the southern region. In the following days, the low-level high pressure system and the abnormal high pressure center strengthened and gradually moved eastward over the ocean, which in turn prompted the Australian heat wave to move eastward with the high pressure system and guided the land heat advection to the ocean, causing the heat wave to spread to the ocean area. Most of the Australian land-based heat waves entering the sea move eastward with the high pressure system. Its upstream area is the Australian desert. Under the influence of land-air feedback, low humidity will amplify the intensity of the downstream heat wave, further prompting the heat wave to be transmitted to the relatively low temperature ocean area, and finally causing the heat wave to enter the sea.

[0079] From an interdecadal scale, wind, as a medium for heat transfer, mostly affects the transfer of heat advection in mid- and low-latitude regions, thereby promoting the formation or migration of heat waves. Compared with the previous 20 years (1981-2000), in the past 20 years (2001-2020), the zonal wind in tropical regions is more consistent with the migration direction of sea-source landfall heat waves, such as Figure 8 As shown in the figure, the easterly wind anomalies in the South China Sea and eastern Australia will be more conducive to the westward transmission of heat waves to the continental region. Correspondingly, the westerly wind anomalies in West Africa, western South America, Western Australia and India are more inclined to transmit heat waves eastward to the adjacent continental waters. Unlike sea-source landfall heat waves, the difference in thermal properties between land and sea (such as the difference in temperature rise between land and sea) makes it easier for high-temperature hot air masses to be transmitted from land to sea, thereby causing heat waves to enter the ocean. Under the influence of anthropogenic climate change, the stronger difference in thermal properties between land and sea will amplify the difference in temperature rise between land and sea, that is, the land will warm up faster than the ocean, which will be more conducive to the transfer of heat from land to ocean. Figure 8 As shown, the difference in sea-land temperature rise is extremely obvious in South Australia, central South America, central Africa and Western Europe, which means that land-based heat waves entering the sea will occur more frequently in this region.

[0080] In summary, the sea-originated landfalling heat wave in China is caused by the interaction between the sea and air and the westward extension of the subtropical high-pressure ridge. The ocean in the northwest Pacific Ocean warms rapidly, and the abnormal zonal easterly wind promotes the advection of heat to the continent. As the subtropical high-pressure ridge continues to extend westward and the low-level high-pressure system in China is further strengthened, the downward airflow causes the cloud cover in the high-pressure system control area to decrease, which in turn leads to regional adiabatic warming and radiation warming, which causes the heat wave to land in China under the joint action of thermal advection, adiabatic warming and radiation warming.

[0081] The Rossby wave train that started in the Indian Ocean gradually moved eastward to form a high-pressure center over Australia. Under the control of the high-pressure system, regional adiabatic warming and radiation warming led to the formation of a heat wave. As the high-pressure system gradually moved eastward, the low humidity in the upstream desert led to enhanced heat advection, which in turn amplified the intensity of the heat wave downstream. The difference in temperature rise between land and sea caused the land to warm far more than the ocean area, which would facilitate the transmission of heat advection to the ocean area. When the high-pressure system gradually moved eastward over the ocean, under the action of thermal advection, radiation warming, and adiabatic warming, the land-based heat wave would migrate into the sea.

[0082] (6) Estimate the risks of landfalling heat waves of marine origin and land-based heat waves entering the sea under future high emission scenarios;

[0083] In order to prevent the extreme evolution of sea-originated landfalling heat waves and land-originated sea-entering heat waves under climate change, this paper estimates the risks of two types of sea-land migration heat waves under future high emission scenarios, so as to inspire people to take targeted protection measures in the face of global warming, and call on the World Meteorological Organization to formulate appropriate policies to solve the severe challenges that will be faced.

[0084] Taking frequency as an example, Fig. 9 As shown, the frequency of two types of sea-land migration heat waves under future high emission scenarios is predicted based on the CM IP6 multi-model ensemble data and the CESM-LENS large sample ensemble data. The results show that sea-sourced landfalling heat waves are increasing in about 95.3% of the world's land areas (+157.8%), which means that more marine heat waves will migrate to land areas in the future, especially in tropical areas. Correspondingly, land-sourced sea-entering heat waves are also showing a significant increasing trend in about 96.3% of the world's ocean areas (+193.5%), and the trend in tropical areas is the most significant, which indicates that the two types of sea-land migration heat waves will become more frequent. The signal-to-noise ratio results show that human activity signals of the two types of sea-land migration heat waves were detected in 87.2% of the world's land areas and 69.1% of the ocean areas, respectively. Reference Fig.10 , although the temperature threshold of heat waves continues to rise, the frequency of the two types of heat waves migrating between sea and land has always been on the rise, and under the CESM-XLENS simulation of future single climate forcing, greenhouse gases promote the frequent occurrence of sea-source landfall heat waves (+183.4%) and land-source sea-entry heat waves (+250.1%). Spatial results show that under the action of greenhouse gas forcing, the risk of sea-source landfall heat waves is greater in the tropics and mid- and high-latitude regions of the Northern Hemisphere, while the risk of land-source sea-entry heat waves increases the most in tropical oceans and the oceans of the Southern Hemisphere. Overall, under the future high-emission climate scenario, sea-source landfall heat waves and land-source sea-entry heat waves will become more frequent (+157.8%, +193.5%), more persistent (+188.3%, +226.2%), more extensive (+487.4%, +479.6%), and more severe (+487.2%, +544.6%).

[0085] See also Fig.11 , Fig.11 It is a schematic diagram of the working of the hardware device of an embodiment of the present invention, and the hardware device specifically includes: a device 401 for tracking the life process of heat waves between sea and land and estimating future risks, a processor 402 and a storage medium 403.

[0086] A device 401 for tracking the life process of heat waves during migration between sea and land and estimating future risks: The device 401 for tracking the life process of heat waves during migration between sea and land and estimating future risks implements a method for tracking the life process of heat waves during migration between sea and land and estimating future risks.

[0087] Processor 402: The processor 402 loads and executes the instructions and data in the storage medium 403 to implement the method for tracking the life process of heat waves between sea and land and predicting future risks.

[0088] Storage medium 403: The storage medium 403 stores instructions and data; the storage medium 403 is used to implement the method for tracking the life process of heat waves between sea and land and predicting future risks.

[0089] The beneficial effects of the present invention are:

[0090] (1) This invention innovatively proposes a method for identifying sea-sourced landfall heat waves and land-sourced sea-entry heat waves, revealing the migration process of heat waves between land and sea. This invention identifies two types of heat waves that migrate between land and sea, clarifies the changes and impacts of the two types of heat waves that migrate between land and sea in spatial and temporal dimensions, and provides a scientific basis for responding to the natural challenges brought about by the two types of heat waves that migrate between land and sea.

[0091] (2) This paper quantifies the spatiotemporal properties of different anthropogenic forcings on the effects of sea-originated landfall heat waves and land-originated sea-entering heat waves, and evaluates the impacts of different anthropogenic forcings on the two types of land-sea migration heat waves, providing new theoretical support for governments and international cooperation organizations to make decisions and recommendations on adapting to and mitigating the effects of climate change on the two types of land-sea migration heat waves.

[0092] (3) The present invention analyzes the atmospheric circulation conditions for the landing or entry of sea-originated heat waves and land-originated heat waves into the sea, and clarifies the migration paths of the two types of sea-land migration heat waves in historical periods, providing groundbreaking theoretical support for the prediction of the two types of sea-land migration heat waves.

[0093] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for tracking the life process of heat waves between sea and land and estimating future risks, characterized by: The method comprises the following steps: Step S1: data download; Step S2: Identify marine-sourced landfalling heat waves and land-sourced sea-entering heat wave events; according to the data downloaded in step S1, threshold discrimination is performed on the warm season daily average temperature based on the dynamic climate threshold method, and grid points with daily average temperatures exceeding the 90th percentile are defined as high-temperature grid points. The Lagrangian three-dimensional space-time tracking method is used to obtain the three-dimensional space-time cube structure of the heat wave, and it is divided into marine heat waves, land heat waves, marine-sourced landfalling heat waves, and land-sourced sea-entering heat waves according to the heat wave generation area and migration process. Step S3: quantify the spatiotemporal attribute characteristics of sea-sourced landfalling heat waves and land-sourced sea-entering heat waves; According to the spatiotemporal cubes of ocean heat waves, land heat waves, sea-sourced landfall heat waves and land-sourced sea-entering heat waves obtained in step S2, the spatiotemporal attribute characteristics of heat wave events are calculated, and the directions of heat wave migration in the regions are statistically divided; Step S4: Detect the impact of different human activities on sea-sourced landfall heat waves and land-sourced sea-entering heat waves; based on the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events obtained in step S3, calculate the relative changes of the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves under three different external forcing scenarios, namely, human forcing, greenhouse gas forcing, and human aerosol forcing, compared with the average values ​​of the historical period, and analyze the impact of different types of human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves; Step S5: The weather scale and decadal scale physical mechanism of the migration and landing or entering the sea of ​​the sea-sourced landfall heat wave and the land-sourced sea-entering heat wave; according to the two types of sea-land migration heat wave events obtained in step S3, the circulation field during the heat wave period is constructed according to the meteorological elements and factors, and the weather scale evolution process and physical mechanism of the migration and landing or entering the sea of ​​the two types of sea-land migration heat waves are analyzed; the decadal scale changes of the meteorological elements and factors of the earth system physical factors driving the migration of the two types of sea-land migration heat waves are analyzed to clarify the decadal physical mechanism driving the migration of heat waves; Step S6: Estimate the risks of sea-sourced landfalling heat waves and land-sourced heat waves entering the sea under future high emission scenarios; combine the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves obtained in step S3 to make future predictions of the spatiotemporal attribute characteristics of the two types of sea-land migration heat wave events, explore the signal-to-noise ratio of the characteristics of the two types of sea-land migration heat wave events under high emission scenarios in the future, and make risk estimates for sea-sourced landfalling heat waves and land-sourced heat waves entering the sea on a global scale.

2. A method for tracking the life process of a heat wave between sea and land and estimating future risks as claimed in claim 1, characterized in that: Step S2 is specifically as follows: S21: Based on 2m temperature data from historical model experiments, natural forcing experiments, greenhouse gas forcing experiments, anthropogenic aerosol forcing experiments and shared socioeconomic pathway high emission scenario simulation experiments, the dynamic climate threshold method with a 30-year window period is used to quantify the annual warm season heat wave temperature threshold; S22: The Lagrangian three-dimensional space-time tracking method identifies global heat wave events in the space-time scale, as follows: if the grid temperature is greater than the temperature threshold obtained in step S21, the grid point is defined as a high temperature grid point; adjacent high temperature grid points in the same time dimension are merged into spatially continuous high temperature patches in the two-dimensional space level; if the overlapping area of ​​the high temperature patches in the continuous time steps is greater than the preset area, and this continuous time step is at least greater than the preset number of days, they are merged into a three-dimensional heat wave event; the life cycle of the three-dimensional heat wave event is at least greater than the preset number of days, and the daily minimum area must be greater than the preset area; S23: Using the mask file data of the global land area and boundaries of step S1, set the minimum landing area threshold of the sea-originated landfall heat wave and the minimum sea entry area threshold of the land-originated sea-entering heat wave, and identify the three-dimensional heat wave events that originate from the ocean or land and then move to the land or ocean as sea-originated landfall heat wave events or land-originated sea-entering heat wave events, respectively.

3. A method for tracking the life process of a heat wave between sea and land and estimating future risks as claimed in claim 2, characterized in that: Step S3 is specifically as follows: The temporal, spatial and attribute characteristics of sea-sourced landfalling heat waves and land-sourced sea-entering heat waves are frequency and life cycle, area and intensity respectively; the frequency is the number of occurrences of the two types of sea-land migration heat wave events each year; the life cycle is the duration of the two types of sea-land migration heat wave events; The area is the impact area of ​​the two types of land-sea migration heat waves; the intensity is the sum of the product of the part of the grid temperature exceeding the threshold and the grid area during the heat wave period.

4. A method for tracking the life process of a heat wave between sea and land and estimating future risks as claimed in claim 3, characterized in that: Step S4 is specifically as follows: The impact of different human activities on sea-originated landfall heat waves and land-originated sea-entering heat waves is detected. According to the time, space and attribute characteristics of the two types of sea-land migration heat wave events under three different external forcing scenarios of anthropogenic forcing, greenhouse gas forcing and anthropogenic aerosol forcing calculated in the specific steps of step S3, the relative changes are compared with the average values ​​of the historical period, so as to analyze and evaluate the impact of human activities on the spatiotemporal attribute characteristics of the two types of sea-land migration heat waves.

5. A method for tracking the life process of a heat wave between sea and land and estimating future risks as claimed in claim 4, characterized in that: Step S5 is specifically as follows: S51: Based on the above initial data set, the atmospheric circulation field during the heat wave is established to analyze the weather-scale physical mechanism during the migration, landing or entry into the sea of ​​the two types of heat wave events between land and sea. Among them, the atmospheric circulation field focuses on the distribution of high-pressure systems in the 850hPa and 500hPa pressure layers during the heat wave migration process and the wind field matching the high-pressure system; According to the initial data set, the interdecadal scale changes in meteorological factors and earth system physical factors that drive the movement of the two types of heat waves between land and sea are analyzed to clarify the interdecadal physical mechanism driving the movement of heat waves. Among them, the sea-source landfalling heat wave focuses on the driving of the latitudinal wind field to make the heat wave land, and the land-source sea-entering heat wave focuses on the difference in thermal properties between land and sea that drives the high temperature of land to transport heat to the ocean, causing the heat wave to enter the sea.

6. A method for tracking the life process of a heat wave between sea and land and estimating future risks as claimed in claim 5, characterized in that: Step S6 is specifically as follows: Based on the three-dimensional spatiotemporal attribute characteristics of the two types of sea-land migration heat waves, future predictions of the attribute characteristics of the two types of sea-land migration heat wave events are made, and the relative changes, risk ratios and signal-to-noise ratios of the two types of sea-land migration heat wave event characteristics under high emission scenarios in the future are explored to conduct risk assessment of the two types of sea-land migration heat waves on a global scale.

7. A storage medium, characterized in that: The storage medium stores instructions and data for implementing a method for tracking the life process of a heat wave between sea and land and predicting future risks as described in any one of claims 1 to 6.

8. A device for tracking the life process of heat waves between sea and land and predicting future risks, characterized by: include: Processor and storage medium; the processor loads and executes instructions and data in the storage medium to implement a method for tracking the life process of migrating heat waves between sea and land and predicting future risks as described in any one of claims 1 to 6.

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