CN-122022149-A - Evaluation method and system for constructing urban forest cooling function baseline and recovering attenuation

CN122022149ACN 122022149 ACN122022149 ACN 122022149ACN-122022149-A

Abstract

The method comprises the steps of obtaining daily meteorological data of a research area to identify start and stop dates of extreme high temperature events, obtaining urban forest coverage distribution information in the research area and near-ground air temperature data or surface temperature data of a first date range, calculating urban forest cooling efficiency data of each date in the first date range, calculating statistical characteristics of the urban forest cooling efficiency data of all dates in a pre-reference period, determining maximum attenuation values and dates of cooling efficiency during the extreme high temperature events, calculating statistical characteristics of the urban forest cooling efficiency data of each sliding window by utilizing sliding windows, and calculating recovery time and rate of urban forest cooling efficiency attenuation according to the base lines and preset discrimination conditions. The method ensures that the attenuation is caused by the extremely high temperature event, and the attenuation degree and the recovery process of the quantized cooling function under the influence of the extremely high temperature event are realized.

Inventors

DONG YULIN
WANG JI
REN ZHIBIN

Assignees

北京市气候中心
中国科学院东北地理与农业生态研究所

Dates

Publication Date: 20260512
Application Date: 20260127

Claims (10)

1. The evaluation method for constructing the urban forest cooling function baseline and recovering the attenuation is characterized by comprising the following steps of: step 1, acquiring daily meteorological data of a research area, and identifying the start and stop date of an extreme high temperature event; Step 2, urban forest coverage distribution information in a research area is obtained, near-ground air temperature data or surface temperature data of a first date range is obtained, urban forest cooling efficiency data of each date in the first date range is calculated, the first date range comprises a date range of the extremely high temperature event, a pre-date range of the extremely high temperature event and a post-date range of the extremely high temperature event, and the pre-date range and the post-date range are adjacent to the date range of the extremely high temperature event; step 3, calculating statistical characteristics of urban forest cooling efficiency data of all dates of a pre-benchmark period as the base line, wherein the pre-date range of the extremely high temperature event comprises the pre-benchmark period; Step 4, determining a maximum attenuation value of cooling efficiency during an extremely high temperature event and a date t d of the maximum attenuation value according to the statistical characteristics; And 5, calculating the statistical characteristics of the urban forest cooling efficiency data of each sliding window by utilizing the sliding window based on the urban forest cooling efficiency data set in a second date range, and calculating the recovery time and the recovery rate of the urban forest cooling efficiency attenuation according to the base line and the preset discrimination conditions, wherein the second date range comprises all dates of which the time is after a date t d in the first date range, and the urban forest cooling efficiency data set in the second date range is a data set ordered according to a time sequence.
2. The method for evaluating the construction and attenuation recovery of the urban forest cooling function baseline according to claim 1, wherein the step 1 is specifically that day-by-day meteorological data of a research area are obtained, if the highest near-ground air temperature is met for d consecutive days to be greater than or equal to a threshold value of Wen Panbie, the highest near-ground air temperature is identified as an extremely high temperature event, the start and stop date of the extremely high temperature event is obtained, and d is an integer greater than or equal to 3.
3. The method for evaluating the construction and attenuation recovery of the urban forest cooling function baseline according to claim 1, wherein the step 2 comprises: Acquiring urban forest coverage distribution information in a research area, and calculating urban forest coverage of each space unit in the research area; Acquiring near-surface air temperature data or surface temperature data of each space unit on each date in a first date range; City forest cooling efficiency data CE (t) for each date in the first date range is calculated for that date.
4. The method for constructing a baseline for urban forest cooling function and evaluating attenuation recovery according to claim 3, wherein the CE (t) is calculated by constructing a linear regression model, wherein x i is an independent variable, y i (t) is a dependent variable, x i represents urban forest coverage of the space unit i, The date t, the near-surface air temperature or the surface temperature of the space unit i are represented, and the absolute value of the regression coefficient of the linear regression model is taken as the CE (t).
5. The method for evaluating urban forest cooling function baseline construction and attenuation recovery according to claim 1, wherein the statistical features comprise a mean μ 0 .
6. The method for estimating a baseline construction and attenuation recovery of a forest cooling function according to claim 5, wherein the step 4 specifically includes calculating an offset of the forest cooling efficiency data of each date in an extreme high temperature event compared with the mean value, wherein the offset is used as a forest cooling efficiency attenuation value, taking a maximum value of the forest cooling efficiency attenuation value as the maximum attenuation value, and determining the date corresponding to the maximum attenuation value.
7. The method for evaluating urban forest cooling function baseline construction and attenuation recovery according to claim 5, wherein the step5 comprises: taking the date of the maximum attenuation value as the sliding starting point of the sliding window, wherein the sliding window is of a time driving type, the sliding direction is a forward direction, and calculating the average value of urban forest cooling efficiency data in each sliding window And standard deviation ; According to the statistical characteristics and the mean value And the standard deviation Judging whether a preset judging condition is met or not, wherein a date which meets the preset judging condition for the first time after a date t d is used as a recovery date t r of urban forest cooling efficiency; And calculating the recovery time of the urban forest cooling efficiency attenuation and the recovery rate of the urban forest cooling efficiency attenuation.
8. The method for constructing and recovering attenuation of urban forest cooling function according to claim 7, wherein said statistical features further comprise standard deviation sigma 0 , and said predetermined criterion is And is also provided with And the date meeting the preset judging condition is the center time of the sliding window meeting the preset judging condition.
9. The method for evaluating urban forest cooling function baseline construction and attenuation recovery according to claim 7, wherein the recovery rate is calculated according to the formula: Wherein T rec is the recovery time of the urban forest cooling efficiency decay, R rec is the recovery rate of the urban forest cooling efficiency decay, Indicating date Is a city forest cooling efficiency data.
10. Evaluation system that city forest cooling function baseline was constructed and decay resumes, its characterized in that includes: the acquisition module is used for acquiring daily meteorological data of a research area and identifying the start and stop date of an extreme high-temperature event; The system comprises an acquisition and calculation module, a calculation module and a control module, wherein the acquisition and calculation module is used for acquiring urban forest coverage distribution information in a research area, acquiring near-ground air temperature data or surface temperature data of a first date range, and calculating urban forest cooling efficiency data of each date in the first date range, wherein the first date range comprises a date range of the extremely high temperature event, a prior date range of the extremely high temperature event and a post date range of the extremely high temperature event, and the prior date range and the post date range are adjacent to the date range of the extremely high temperature event; The first calculation module is used for calculating statistical characteristics of urban forest cooling efficiency data of all dates in a pre-benchmark period as the base line, and the pre-date range of the extremely high temperature event comprises the pre-benchmark period; The attenuation determining module is used for determining a maximum attenuation value of cooling efficiency during an extremely high temperature event and a date t d of the maximum attenuation value according to the statistical characteristics; The second calculation module is used for calculating the statistical characteristics of the urban forest cooling efficiency data of each sliding window by utilizing the sliding window based on the urban forest cooling efficiency data set in a second date range, and calculating the recovery time and the recovery rate of the urban forest cooling efficiency attenuation according to the base line and the preset discrimination conditions, wherein the second date range comprises all dates of which the time is after a date t d in the first date range, and the urban forest cooling efficiency data set in the second date range is a data set ordered according to a time sequence.

Description

Evaluation method and system for constructing urban forest cooling function baseline and recovering attenuation Technical Field The disclosure relates to the technical field of urban ecology and climate adaptation evaluation, in particular to an evaluation method and an evaluation system for constructing an urban forest cooling function baseline and recovering attenuation. Background The extremely high Wen Shijian (also called heat wave) is shown as that the air temperature is obviously higher than the local climate normal level in a plurality of continuous days, is easy to be overlapped with the urban heat island effect, and has obvious influence on the urban heat exposure level and the ecological regulation function. Extreme high temperature events can cause disturbances to the structure and function of the urban ecosystem, thereby weakening the adaptation and regulation ability of the city under extreme climatic conditions. Urban forests include greenery elements with arbor communities as the main body, such as pavement trees, guard forests, and public land in the built-up area. Urban forests can effectively reduce near-surface air temperature and surface temperature through the processes of canopy shading, transpiration, change of surface radiant energy distribution and the like, and a remarkable cooling function is formed. The urban forest cooling function is taken as an important component of the urban ecological system function, and plays an important role in urban thermal environment regulation and climate adaptation type urban construction. Under the influence of an extremely high temperature event, the urban forest cooling function can have nonlinear response characteristics. Under the short-term high-temperature condition, the effect of cooling can be improved by enhancing the transpiration, and the closed air holes and limited physiological activities can be caused by continuous high temperature and water stress, so that the attenuation of the cooling function is caused. The above-described changes typically have significant time series characteristics, involving extremely high Wen Shijian pre-occurrence functional states, functional deviations during events, and recovery procedures after the event has ended. The existing toughness assessment method for urban forest ecological functions is mostly based on simple comparison of long-term characteristics or external interference front and back states, but has the problems that natural fluctuation and functional change caused by extreme events are difficult to distinguish, and real recovery process is difficult to accurately identify, so that the assessment method and system for constructing and attenuating recovery of urban forest cooling function baselines are used for realizing more scientific and more application value assessment. Disclosure of Invention Based on the above, it is necessary to provide an evaluation method and system for constructing and recovering the baseline of the urban forest cooling function for the problems that it is difficult to distinguish the natural fluctuation from the functional change caused by the extremely high temperature event, and it is difficult to quantify the attenuation degree and recovery process of the cooling function under the influence of the extremely high temperature event. In order to solve the problems, the present disclosure adopts the following technical scheme: In a first aspect, the present disclosure provides an evaluation method for urban forest cooling function baseline construction and attenuation recovery, including the steps of: step 1, acquiring daily meteorological data of a research area, and identifying the start and stop date of an extreme high temperature event; Step 2, urban forest coverage distribution information in a research area is obtained, near-ground air temperature data or surface temperature data of a first date range is obtained, urban forest cooling efficiency data of each date in the first date range is calculated, the first date range comprises a date range of the extremely high temperature event, a pre-date range of the extremely high temperature event and a post-date range of the extremely high temperature event, and the pre-date range and the post-date range are adjacent to the date range of the extremely high temperature event; step 3, calculating statistical characteristics of urban forest cooling efficiency data of all dates of a pre-benchmark period as the base line, wherein the pre-date range of the extremely high temperature event comprises the pre-benchmark period; Step 4, determining a maximum attenuation value of cooling efficiency during an extremely high temperature event and a date t d of the maximum attenuation value according to the statistical characteristics; And 5, calculating the statistical characteristics of the urban forest cooling efficiency data of each sliding window by utilizing the sliding window based on the urban forest cooling efficienc