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近年来,针对日益繁忙的空中交通与不断增长的人影作业需求的矛盾,研制开发了贵州省空域自动化系统,为进一步了解系统在实际人影作业中的应用情况及效果,利用2014-2020年全省人影地面作业数据及全国人工影响天气作业信息上报等资料,对使用系统前后的地面人影申报与批复流程、作业情况、空域申请及批复耗时等进行对比分析,结果表明:(1)简化了业务流程,使用系统后一个申请批复流程从以往的至少需打8个电话缩短至2个,平均每个作业点批复耗时减少1.5 min,年均有效批复率较使用系统前提高2.8%,新型的扁平式管理,减少了管理层级,提高了业务效率。(2)系统投入使用后高炮年均作业次数较使用系统前增长20%,火箭年均作业次数较使用系统前增长82%,且年均获得作业时长较使用系统前增长37%,在实现人影作业多点同时申请与批复的同时,解决了电话占线等问题,提高了作业及时申请的成功率。(3)提高作业信息上传准确率,使用系统后年均人影地面作业信息上报及时率较使用系统前提高2.3%。 相似文献
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在人工影响天气作业中,地面作业基本上都是使用37高炮和火箭发射装置.在目前高炮、火箭并存、同时使用的时期,我们注重充分挖掘两种火器各自的作业优势,并在人影作业中科学地相互配合使用,使现有火器资源得到充分的利用,达到即经济、节能,又能取得好的作业效果,实现人工影响天气防御和减轻气象灾害的目的. 相似文献
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本文根据人工影响天气(以下简称人影)作业安全射界管理需求,讨论分析了影响人影作业安全射界因素包括装备性能、弹药稳定性、高空气流、站点海拔和人员操作水平等,提出一种人影作业安全射界精细化绘制思路和方法,设计开发了基于高分辨率卫星影像数据和数字高程模型数据(以下简称DEM数据)人工标识技术的人影安全射界绘制系统。经实践应用,该系统输出的人影作业安全射界图,可解决传统射界图安全标记要素不全、绘制分辨率不高、信息化程度低等问题,对提升作业效益和安全管理水平具有一定的实用价值,可以向开展人影作业的各级单位推广使用。 相似文献
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人工增雨必须在有利于降水的天气形势下,通过气象雷达的探测,寻找有利于人工增雨的云系,把降水云体空间平面位置与垂直结构迅速而直观地显示出来,连续观测雷达降水回波特征(参数)的演变,来指导高炮的作业,由于在人工增雨作业中,气象雷达起着监测天气系统、选择催化云和观测催化效果的作用,所以气象雷达的配合就成为 相似文献
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效果评估仍是人工影响天气研究面临的困难问题,数值模式在催化效果的评估方面有望发挥更大作用,建立能够模拟真实催化过程的数值模式是一条可行的途径。本文对一套三维中尺度催化模式进行了改进,采用了新的碘化银核化计算方案,在模式中增加了人工冰晶预报量及相关微物理过程,并实现了对地面火箭和高炮作业方式的仿真模拟。使用改进后的模式,采用500 m的水平分辨率,模拟了2019年9月1日华北地区一次对流云系的人工消减雨作业过程,对催化作业的消减雨效果进行了数值评估,并对碘化银在对流云中的核化特征及其催化作用机制进行了分析。结果表明:(1)催化作业对目标云系的雷达回波强度产生了一些影响,催化导致较多降水粒子滞留在高空,使得云体上部的回波强度略有增加,云体中下部的回波强度减弱,但催化作业并未改变目标云系雷达回波的自然演变趋势。(2)催化作业达到了一定的消减雨效果,作业区下游出现大面积减雨区,降水总量减少,降水强度减弱,局地最大减雨量为0.27 mm,主要影响区的平均减雨率为5.1%。(3)碘化银催化剂主要的核化方式为凝结冻结核化,其次为接触冻结核化。(4)催化作业造成了过量播撒,人工冰晶的成长占据竞争优势,... 相似文献
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河南省飞机人工影响天气空地数据传输系统的建设及应用 总被引:2,自引:0,他引:2
基于飞机人工影响天气作业机上作业人员与地面指挥中心信息交换的需求,河南省人影中心建立了具有中继能力的远距离无线信息传输系统,实现了飞机作业空、地信息双向和多点实时交换,并且基于Micaps平台开发了一套空、地实时传输数据的显示分析系统,实现了飞机上作业人员实时得到地面各种气象探测资料以及地面人影作业指挥中心实时得到飞机飞行轨迹和机上实时探测数据。 相似文献
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大气气溶胶吸收系数的测量 总被引:9,自引:4,他引:9
本文讨论了大气气溶胶吸收系数的测量,并介绍了我系根据毛玻璃屏积分法设计的测量系统。根据在北京中关村地区取样观测的结果,在采暖期,气溶胶吸收系数变化于10~(-3)—10~(-4)m~(-1)之间,而在非采暖期,其值约为10~(-4)m~(-1)量级。若利用当量碳的概念,则在采暖期当量碳浓度占气溶胶总浓度的50—60%,而在非采暖期,其比例为30—37%。 相似文献
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Atmospheric boundary layer research at Cabauw 总被引:1,自引:1,他引:0
At Cabauw, The Netherlands, a 213 m high mast specifically built for meteorological research has been operational since 1973. Its site, construction, instrumentation and observation programs are reviewed. Regarding analysis of the boundary layer at Cabauw, the following subjects are discussed: - terrain roughness; - Monin-Obukhov theory in practice; - the structure of stable boundary layers; - observed evolution of fog layers; - inversion rise and early morning entrainment; - use of the geostrophic wind as a predictor for wind profiles; - height variation of wind climate statistics; - air pollution applications: long range transport and short range dispersion; - dependence of sound wave propagation on boundary-layer structure; - testing of weather and climate models. 相似文献
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Evapotranspiration is a major component of both the energy and water balances of wetland tundra environments during the thaw season. Reliable estimates of evapotranspiration are required in the analysis of climatological and hydrological processes occurring within a wetland and in interfacing the surface climate with atmospheric processes. Where direct measurements are unavailable, models designed to accurately predict evapotranspiration for a particular wetland are used.This paper evaluates the performance, sensitivity and limitations of three physically-based, one-dimensional models in the simulation of evaporation from a wetland sedge tundra in the Hudson Bay Lowland near Churchill, Manitoba. The surface of the study site consists of near-saturated peat soil with a sparse sedge canopy and a constantly varying coverage of standing water. Measured evaporation used the Bowen ratio energy balance approach, to which the model results were compared. The comparisons were conducted with hourly and daily simulations.The three models are the Penman-Monteith model, the Shuttleworth-Wallace sparse canopy model and a modified Penman-Monteith model which is weighted for surface area of the evaporation sources.Results from the study suggest that the weighted Penman-Monteith model has the highest potential for use as a predictive tool. In all three cases, the importance of accurately measuring the surface area of each evaporation source is recognized. The difficulty in determining a representative surface resistance for each source and the associated problems in modelling without it are discussed.
List of Symbols
Models BREB Bowen ratio energy balance - P-M Penman-Monteith combination - S-W Shuttleworth-Wallace combination - W-P-M Weighted Penman-Monteith combination Other AE Available energy-all surfaces - AE c Available energy-canopy (S-W, W-P-M) - AE s Available energy-bare soil (S-W, W-P-M) - AE w Available energy-open water (W-P-M) - C p Specific heat of air - D Vapor pressure deficit - DAI Dead area index - FAI Foliage area index - LAI Leaf area index - Q * Net radiation - Q e Latent heat flux-total - Q ec Latent heat flux-canopy (S-W, W-P-M) - Q es Latent heat flux-bare soil (S-W, W-P-M) - Q ew Latent heat flux-open water (W-P-M) - Q g ground heat flux - Q h Sensible heat flux - S Proportion of area in bare soil - W Proportion of surface in open water - r a Aerodynamic resistance (P-M, W-P-M) - r c Canopy resistance - r s Generalized optimized surface resistance - r st Stomatal resistance - r c a Bulk boundary layer resistance (S-W) - r s a Aerodynamic resistance below mean canopy level (S-W) - r s s Soil surface resistance (S-W, W-P-M) Greek Bowen ratio - Psychrometer constant - Air density - Slope of saturation vapour pressure vs temperature curve 相似文献15.
A high resolution global model of the terrestrial biosphere is developed to estimate changes in nitrous oxide (N2O) emissions from 1860–1990. The model is driven by four anthropogenic perturbations, including land use change and nitrogen inputs from fertilizer, livestock manure, and atmospheric deposition of fossil fuel NO
x
. Global soil nitrogen mineralization, volatilization, and leaching fluxes are estimated by the model and converted to N2O emissions based on broad assumptions about their associated N2O yields. From 1860–1990, global N2O emissions associated with soil nitrogen mineralization are estimated to have decreased slightly from 5.9 to 5.7 Tg N/yr, due mainly to land clearing, while N2O emissions associated with volatilization and leaching of excess mineral nitrogen are estimated to have increased sharply from 0.45 to 3.3 Tg N/yr, due to all four anthropogenic perturbations. Taking into account the impact of each perturbation on soil nitrogen mineralization and on volatilization and leaching of excess mineral nitrogen, global 1990 N2O emissions of 1.4, 0.7, 0.4 and 0.08 Tg N/yr are attributed to fertilizer, livestock manure, land clearing and atmospheric deposition of fossil fuel NO
x
, respectively. Consideration of both the short and long-term fates of fertilizer nitrogen indicates that the N2O/fertilizer-N yield may be 2% or more.C. NBM Definitions
AET
mon
(cm H2O) = monthly actual evapotranspiration
-
AET
ann
(cm H2O) = annual actual evapotranspiration
-
age
h
(years) = stand age of herbaceous biomass
-
age
w
(years) = stand age of woody biomass
-
atmblc
(gC/m2/month) = net flux of CO2 from grid
-
biotoc
(gC/g biomass) = 0.50 = convert g biomass to g C
-
beff
h
= 0.8 = fraction of cleared herbaceous litter that is burned
-
beff
w
= 0.4 = fraction of cleared woody litter that is burned
-
bfmin
= 0.5 = fraction of burned N litter that is mineralized or converted to reactive gases which rapidly redeposit. Remainder assumed pyrodenitrified to N2. + N2O
-
bprob
= probability that burned litter will be burned
-
burn
h
(gC/m2/month) = herbaceous litter burned after land clearing
-
burn
w
(gC/m2/month) = woody litter burned after land clearing
-
cbiomsh
(gC/m2) = C herbaceous biomass pool
-
cbiomsw
(gC/m2) = C woody biomass pool
-
clear
(gC/m2/month) = woody litter C removed by land clearing
-
clearn
(gN/m2/month) = woody litter N removed by land clearing
-
cldh
(month–1) = herbaceous litter decomposition coefficient
-
cldw
(month–1) = woody litter decomposition coefficient
-
clittrh
(gC/m2) = C herbaceous litter pool
-
clittrw
(gC/m2) = C woody litter pool
-
clph
(month–1) = herbaceous litter production coefficient
-
clpw
(month–1) = woody litter production coefficient
-
cnrath
(gC/gN) = C/N ratio in herbaceous phytomass
-
cnrats
(gC/gN) = C/N ratio in soil organic matter
-
cnratt
(gC/gN) = average C/N ratio in total phytomass
-
cnratw
(gC/gN) = C/N ratio in woody phytomass
-
crod
(month–1) = forest clearing coefficient
-
csocd
(month–1) = actual soil organic matter decompostion coefficient
-
decmult
decomposition coefficient multiplier; natural =1.0; agricultural =1.0 (1.2 in sensitivity test)
-
fertmin
(gN/m2/month) = inorganic fertilizer input
-
fleach
fraction of excess inorganic N that is leached
-
fligh
(g Lignin/ g C) = lignin fraction of herbaceous litter C
-
fligw
(g Lignin/ g C) = 0.3 = lignin fraction of woody litter C
-
fln2o
= .01–.02 = fraction of leached N emitted as N2O
-
fnav
= 0.95 = fraction of mineral N available to plants
-
fosdep
(gN/m2/month) = wet and dry atmospheric deposition of fossil fuel NO
x
-
fresph
= 0.5 = fraction of herbaceous litter decomposition that goes to CO2 respiration
-
fresps
= 0.51 + .068 * sand = fraction of soil organic matter decomposition that goes to CO2 respiration
-
frespw
= 0.3 * (* see comments in Section 2.3 under decomposition) = fraction of woody litter decomposition that goes to CO2 respiration
-
fsoil
= ratio of NPP measured on given FAO soil type to NPFmiami
-
fstruct
= 0.15 + 0.018 * ligton = fraction of herbaceous litter going to structural/woody pool
-
fvn2o
= .05–.10 = fraction of excess volatilized mineral N emitted as N2O
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fvol
= .02 = fraction of gross mineralization flux and excess mineral N volatilized
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fyield
ratio of total agricultural NPP in a given country in 1980 to total NPPmiami of all displaced natural grids in that country
-
gimmob
h
(gN/m2/month) = gross immobilization of inorganic N into microbial biomass due to decomposition of herbaceous litter
-
gimmob
s
(gN/m2/month) = gross immobilization of inorganic N into microbial biomass due to decomposition of soil organic matter
-
gimmob
w
(gN/m2/month) = gross immobilization of inorganic N into microbial biomass due to decomposition of woody litter
-
graze
(gC/m2/month) = C herbaceous biomass grazed by livestock
-
grazen
(gN/m2/month) = N herbaceous biomass grazed by livestock
-
growth
h
(gC/m2/month) = herbaceous litter incorporated into microbial biomass
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growth
w
(gC/m2/month) = woody litter incorporated into microbial biomass
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gromin
h
(gN/m2/month) = gross N mineralization due to decomposition and burning of herbaceous litter
-
gromin
s
(gN/m2/month) = gross N mineralization due to decomposition of soil organic matter
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gromin
w
(gN/m2/month) = gross N mineralization due to decomposition and burning of woody litter
-
herb
herbaceous fraction by weight of total biomass
-
leach
(gN/m2/month) = leaching (& volatilization) losses of excess inorganic N
-
ligton
(g lignin-C/gN) = lignin/N ratio in fresh herbaceous litter
-
LP
h
(gC/m2/month)= C herbaceous litter production
-
LP
(gC/m2/month) = C woody litter production
-
LPN
h
(gN/m2/month) = N herbaceous litter production
-
LPN
W
(gN/m2/month) = N woody litter production
-
manco2
(gC/m2/month) = grazed C respired by livestock
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manlit
(gC/m2/month) = C manure input (feces + urine)
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n2oint
(gN/m2/month) = intercept of N2O flux vs gromin regression
-
n2oleach
(gN/m2/month) = N2O flux associated with leaching and volatilization of excess inorganic N
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n2onat
(gN/m2/month) = natural N2O flux from soils
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n2oslope
slope of N2O flux vs gromin regression
-
nbiomsh
(gN/m2) = N herbaceous biomass pool
-
nbiomsw
(gN/m2) = N woody biomass pool
-
nfix
(gN/m2/month) = N2 fixation + natural atmospheric deposition
-
nlittrh
(gN/m2) = N herbaceous litter pool
-
nlittrw
(gN/m2) = N woody litter pool
-
nmanlit
(gN/m2/month) = organic N manure input (feces)
-
nmanmin
(gN/m2/month) = inorganic N manure input (urine)
-
nmin
(gN/m2) = inorganic N pool
-
NPP
acth
(gC/m2/month)= actual herbaceous net primary productivity
-
NPP
actw
(gC/m2/month) = actual woody net primary productivity
-
nvol
(gN/m2/month) = volatilization losses from inorganic N pool
-
plntnav
(gN/m2/month)= mineral N available to plants
-
plntup
h
(gN/m2/month) = inorganic N incorporated into herbaceous biomass
-
plntup
w
(gN/m2/month) = inorganic N incorporated into woody biomass
-
precip
ann
(mm) = mean annual precipitation
-
precip
mon
(mm) = mean monthly precipitation
-
pyroden
h
(gN/m2/month) = burned herbaceous litter N that is pyrodenitrified to N2
-
pyroden
w
(gN/m2/month) = burned woody litter N that is pyrodenitrified to N2
-
recyc
fraction of N that is retranslocated before senescence
-
resp
h
(gC/m2/month) = herbaceous litter CO2 respiration
-
resp
s
(gC/m2/month) = soil organic carbon CO2 respiration
-
resp
w
(gC/m2/month) = woody litter CO2 respiration
-
sand
sand fraction of soil
-
satrat
ratio of maximum NPP to N-limited NPP
-
soiloc
(gC/m2) = soil organic C pool
-
soilon
(gN/m2) = soil organic N pool
-
temp
ann
(°C) = mean annual temperature
-
temp
mon
(°C) = mean monthly temperature
Now at the NOAA Aeronomy Laboratory, Boulder, Colorado. 相似文献
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A Forest SO2 Absorption Model (ForSAM) was developed to simulate (1) SO2 plume dispersion from an emission source, (2) subsequent SO2 absorption by coniferous forests growing downwind from the source. There are three modules: (1) a buoyancy module, (2) a dispersion module, and (3) a foliar absorption module. These modules were used to calculate hourly abovecanopy SO2 concentrations and in-canopy deposition velocities, as well as daily amounts of SO2 absorbed by the forest canopy for downwind distances to 42 km. Model performance testing was done with meteorological data (including ambient SO2 concentrations) collected at various locations downwind from a coal-burning power generator at Grand Lake in central New Brunswick, Canada. Annual SO2 emissions from this facility amounted to about 30,000 tonnes. Calculated SO2 concentrations were similar to those obtained in the field. Calculated SO2 deposition velocities generally agreed with published values.Notation
c
air parcel cooling parameter (non-dimensional)
-
E
foliar absorption quotient (non-dimensional)
-
f
areal fraction of foliage free from water (non-dimensional)
-
f
w
SO2 content of air parcel
-
h
height of the surface layer (m)
-
H
height of the convective mixing layer (m)
-
H
stack
stack height (m)
-
k
time level
-
k
drag
coefficient of drag on the air parcel (non-dimensional)
-
K
z
eddy viscosity coefficient for SO2 (m2·s–1)
-
L
Monin-Obukhov length scale (m)
-
L
A
single-sided leaf area index (LAI)
-
n
degree-of-sky cloudiness (non-dimensional)
-
N
number of parcels released with every puff (non-dimensional)
- PAR
photosynthetically active radiation (W m–2)
-
Q
emission rate (kg s–2)
-
r
b
diffusive boundary-layer resistance (s m–1)
-
r
c
canopy resistance (s m–1)
-
r
cuticle
cuticular resistance (s m–1)
-
r
m
mesophyllic resistance (s m–1)
-
r
s
stomatal resistance (s m–1)
-
r
exit
smokestack exit radius (m)
-
R
normally distributed random variable with mean of zero and variance of t (s)
-
u
*
frictional velocity scale,
(m s–1)
-
v
lateral wind vector (m s–1)
-
v
d
SO2 dry deposition velocity (m s–1)
- VCD
water vapour deficit (mb)
-
z
can
mean tree height (m)
-
Z
zenith position of the sun (deg)
-
environmental lapse rate (°C m–1)
-
dry adiabatic lapse rate (0.00986°C m–1)
-
von Kármán's constant (0.04)
-
B
vertical velocities initiated by buoyancy (m s–1)
-
canopy extinction coefficient (non-dimensional)
- ()a
denotes ambient conditions
- ()can
denotes conditions at the top of the forest canopy
- ()h
denotes conditions at the top of the surface layer
- ()H
denotes conditions at the top of the mixed layer
- ()s
denotes conditions at the canopy surface
- ()p
denotes conditions of the air parcels 相似文献
17.
This paper discusses the measurement of the absorption coefficient of atmospheric aerosols and its measuring system based on the principle of integrating plate. Measurements in Beijing show that the absorption coefficient of atmospheric aerosols in the heating period varies in a range of 10-3 to 10-4 m-1 and in the non-heating period, its values are near 10-4m-1. 相似文献
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19.
根据共享社会经济情景(SSPs)分为“双碳”路径(SSP1-1.9、SSP1-2.6、SSP2-4.5、SSP4-3.4、SSP4-6.0)和“高碳”路径(SSP3-7.0、SSP5-8.5)。在碳达峰(2028—2032年)和碳中和(2058—2062年)两个时期,采用5个气候模式,7个情景驱动SWAT水文模型,分析赣江流域径流演变特征,主要结论如下:1961—2017年赣江流域观测到的年均气温以0.17℃/(10 a)的速率呈显著上升趋势(p<0.01),降水以17 mm/(10 a)的速率呈不显著上升。“双碳”和“高碳”路径下,2021—2100年赣江流域均呈现暖湿态,气温持续变暖,降水有所增加;碳达峰、碳中和时期,“双碳”路径下年径流呈现增加趋势;“双碳”路径下,月径流在汛期呈现增加趋势,枯水期在SSP1-1.9、SSP1-2.6、SSP2-4.5、SSP4-3.4下呈现增加趋势,在SSP4-6.0下呈现减少趋势。“双碳”路径下极端水文事件强度将可能小于“高碳”路径。 相似文献
20.
A two dimensional model has been set up to investigate the circulation induced by an urban heat island in the absence of synoptic winds. The boundary conditions need to be formulated carefully and due to difficulties arising here, we restrict our attention to cases of initially stable thermal stratification. Heat island circulations are allowed to develop from rest and prior to the appearance of the final symmetric double cell pattern, a transitional multi-cell pattern is observed in some cases. The influence on the steady state circulation of various parameters is studied, among which are eddy transfer coefficients, the heat island intensity, the initial temperature stratification and the heat island size. Some results are presented for a case in which differential surface cooling beneath an initially stable atmosphere produces a circulation and an unstable layer capped by an elevated inversion over the city. It is hoped that this case is vaguely representative of the night-time heat island with no geostrophic wind.Notation cp
Specific heat at constant pressure
- g
Acceleration due to gravity
- H
Top of integration region
- Kz
Vertical eddy transfer coefficient
- Kx, KxH, Kxm
Horizontal eddy transfer coefficients for heat and momentum
- l
ixing length
- p
Pressure
- p0
Reference surface pressure (1000 mb)
- PH (x, t)
Pressure at z = H
- R
Specific gas constant for dry air
- t
Time
- u, w
Horizontal and vertical velocities
- x, z
Horizontal and vertical coordinates
- x1, x2
Positions of discontinuities in surface temperature field (see Figure 2)
- xa
Heat island half-width
- xb
Boundary of integration region
-
Parameter in formula for eddy coefficients (variable-K case) = 18.0
- s
Intensity of heat island
-
Potential temperature field
-
Reference absolute temperature (variable-K case)
- r
Reference temperature (° C)
- s
Surface temperature
- Q
Air density 相似文献