W1-2 - P3中尺度研究室

Chapter O: A Historical Review of Atmospheric
Sciences (Meteorology)
NTU/DAS-Atmospheric Sciences 101
1. 由北歐學派到芝加哥學派 (天氣動力學
發展)
2. 電子計算機發明，大量資料儲存和快速
運算 （數值天氣預報）
3. 衛星科技發展，走出地球，從太空看天
下（全球氣候問題的開端）
4. 全球氣候變遷，溫室氣體大量增加，全
球暖化和南極臭氧洞（人與自然）
•
三八啦！誤會大了 輕颱三巴是「秋天的颱風」非「秋颱」
(Nownews, 2012/9/12 10am)
記者陳鈞凱／
綜合報導
許多人或許都以為
，秋天來的颱風就
叫做「秋颱」？事
實上誤會大了！並
不是在秋天影響台
灣的颱風都是秋颱
，中央氣象局解釋
，會產生強烈風勢
及雨勢、令人聞之
色變的典型秋颱，
必須跟東北季風產
生共伴效應，才叫
「秋颱」，所以最
近常被媒體報導冠
上「秋颱」兩字的
輕度颱風三巴，充
其量只能叫做「秋
天的颱風」。
850 hPa weather map (temp, height, and winds)
Analysis and forecast maps for Northern hemisphere 500hPa
geo-potential height
(polar stereographic projection)
Early development of Meteorology
氣象學是研究大氣與其相關物理化學現象的科學
希臘哲學家 亞里斯多德（340 BC）所著Meteorologica 一書說明天氣與氣候相關的知識，討論雲、雨、雪、
風、雹、雷、颱風等天氣現象。”meteoros”希臘字意指在高空中。Meteorology一字表示由高空掉落以及
在空氣中各種現象稱之。氣象學成為『自然科學』源於利用科學儀器來量度氣象參數。
Ancient India, Upanishads discussion about the cloud formation and rain and seasonal cycles caused by the
earth movement around the sun.
350BC, Aristotle wrote Meteorologica, is considered as the founder of meteorology, discuss the hydrological
cycle in the earth atmosphere
Greek scientist, Theophrastus, Book of Signs, weather forecasting
1441, King Sejong’s son, Prince Munjong  rain gauge (Joseon Dynasty Korea)
1450, Leone Battista Alberti, awinging-plate anemometer
1607, Galileo Galilei, thermoscope
1611, Johannes Kepler, snow crystals formation
1643, Evangelista Torricelli, mercury barometer
1662, Christopher Wren, self-emptying tipping bucket rain gauge
1714, Gabriel Fahrenheit, mercury thermometer (a reliable one)
1742, Anders Celsius, Celsius temperature scale
1783, Horace-Benedict Saussure, hair hygrometer
氣象要素變化和天氣現象之關係開始建立。
Recent development of Atmospheric Sciences
(19世紀)：1842年電報系統發展，長程通訊對氣象事業發展影響深遠; 1869
年第一張繪製等壓線之天氣圖
1920年挪威學派 (The Bergen School) 氣團與鋒面概念建立極鋒理論, 近代
天氣學的開端 (Bjerknes父子)
1940年芝加哥學派 (The Chicago School),氣球探空,西風噴流,羅士比波(西
風帶長波理論),WMO成立
1950年電子計算機,天氣動力學理論建立,數值天氣預報
1960年氣象衛星(泰洛斯1號),全球天氣監測 (熱帶海洋氣象),氣象雷達
1970年複雜衛星系統,超大快速電子計算機,全球氣候與環境變遷,聖嬰與南
方震盪(ENSO)
1980年氣候理論快速發展,南極臭氧洞,全球暖化
1990年迄今劇烈天氣極即時監測網絡(晴空雷達,偏振雷達),中長期氣候預
報系統
2000from understanding to action! From weather/climate prediction to
weather modification and climate hazard mitigation
Vilhelm F. K. Bjerknes
(1862-1951)
Jacob A. B. Bjerknes
(1897-1975)
BJERKNES
•
Pioneers in modern meteorology and climate research
•
Born on the 14th March, 1862 in Oslo (Christiania), Vilhelm Frimann Koren Bjerknes was destined for a career in science.
He obtained a Master’s degree in mathematics and physics in Kristiania 1888 and continued his studies in Paris and Bonn,
where his work together with Heinrich Hertz on electrical resonance resulted in a doctoral thesis in 1892.
While he was professor at the University of Stockholm (1895-1906), Vilhelm Bjerknes worked out a synthesis of
hydrodynamics and thermodynamics, which was applicable to large-scale circulation in the atmosphere and the oceans. Based
on his theorems, he published a programatic paper in 1904 on “The problem of weather forecasting as a problem in
mechanics and physics” (Meteorologische Zeitschrift, Wien 21:1-7) where he postulated the procedure now know as
numerical weather forecasting. Once at the Geophysical Institute in Bergen (1917-1926), he laid the foundations of the Bergen
School of Meteorology. Bjerknes established a network of weather observations in Norway that collected data that would be of
great importance in their later work. Together with his son Jacob, also an acknowledged meteorologist, he put forward the
acclaimed “polar front theory”. In analogy with WWI battlefronts, the meteorological “fronts” form the boundaries between
cold and warm air masses and their theories and models suggested that weather activity is concentrated in these relatively
narrow zones, where mid-latitude cyclones were proposed to form, live, and decay. Today, practically all weather forecasting is
based on Bjerknes principles described in his paper of 1904 and made possible thanks to the enormous computer capabilities of
today. The work by Bjerknes marked a turning point in atmospheric science and remains remarkably unaltered to this day.
Further, Vilhelm and Jacob Bjerknes conducted several studies of the ocean circulation, air-sea exchange, and climate
variability that laid the basis for modern research on climate change and the role of the ocean in the climate system. Jacob
Bjerknes carried out pioneer studies on the North Atlantic Oscillation (NAO), by describing its major
features and how it influences the currents and temperature conditions in the North Atlantic. Nowadays the vision provided by
the Bjerknes family has been taken further by simulating climate variability in models that couple the atmosphere, land, and
oceans, in an attempt to estimate the response of the climate system to driving forces.
The Centre is named is thus named as a tribute to their efforts.
•
•
•
• (BCCR: Bjerknes Center for Climate Research, Norway)
Polar front theory and station weather elements
Weather elements:
1.
Temperature
2.
Precipitation (rain, snow, hail, ice)
3.
Winds (horizontal, speed and direction)
4.
Pressure
5.
Water vapor (dew point)
6.
Cloudiness (sky conditions)
7.
Visibility, air quality (dust/air pollution)
Carl-Gustaf Rossby: Long waves in the westerly
Upper air chart
Jule Charney’s influence on modern
Meteorology/long waves vs polar front
(1982, BAMS)
Jule Charney的博士論文『斜壓西風帶中的長波擾動』具體
貢獻可以歸納成兩點
（一）利用尺度分析觀念，將複雜問題簡單化，可以利用
數學獲得解析解，建立天氣動力基礎理論架構。
（二）由數學解，獲得溫帶鋒面是西風噴流下長波擾動局
部不穩定產生的現象，不是早期認為鋒面造成西風噴流。
（因果關係的澄清）
Early days
of NWP
數值模擬-數值天氣預報(NWP)
DVj/Dt = Aj =  Fj /, (Vj = [u, v, w] ) (momentum conservation)
 Fj = gravity, pressure gradient, Coriolis, friction
DT/Dt = H =  Qi (energy conservation)
Qi = radiation, sensible heat, latent heat
Di /Dt =  Si (mass conservation)
 Si = cloud, rain, ice, snow
P = RT (ideal gas law)
NWP is a highly non linear initial and boundary value problem!
Meteorological variables: Vj (u, v, w), P, i, T 
(precipitation)
近海面氣流線
瑪莉亞颱風
美國海軍艦隊全球模式
FNMOC NOGAPS
桑美颱風
第10號颱風
海面波浪高度
初始場08/07/20L
輸出08/09/20時至08/11/08時
海面風場、浪場及海平面氣壓降雨圖
地面氣壓和降雨
大氣科學-氣象部份的最新發展
1.
2.
3.
4.
劇烈天氣之即時監測與預報：遙測設備的蓬勃發展以及社會需求。氣象衛
星、氣象雷達、以及氣象飛機等。這方面的研究需要和防災應用學門專家
的通力合作。
大氣與海洋的交互作用：季風和聖嬰現象的研究，並延伸至短期氣候變化
的預測，這方面的研究關連到與海洋學家的合力研究。
大氣問題的數值模擬：數值模擬天氣及預報，利用電腦自動計算結果經人
為詮釋來預報天氣。這方面的研究關連到和應用數學家及電子計算機專家
的合作。
空氣污染問題：熱島效應,全球增溫,南極臭氧洞等。這方面的研究關連到
與大氣化學家的通力合作。
(氣候與其他星球部份)
1. 探討地球氣候變遷的歷史(地球系統)：這方面的研究牽涉到與地球化學家，
地質學家，海洋學家，以及冰河學家們的合作。探討百年甚至千年氣候變
化的原因與未來之可能趨勢，並討論因應對策。
2. 太陽表面擾動所造成地球高層大氣各種特殊現象產生的物理過程：磁暴/
太陽風→通訊、太空天氣預報的計畫。這方面的研究牽涉到高層大氣物理
學家，太陽物理學家及太空物理學家們的通力合作。
3. 其他星球的大氣探索：遙測技術,實地太空觀測（太空船）,近代物理之輻
射理論的發展與應用等。
災變天氣之監測和預報
動研民按風預氣
溝判眾氣來測象
通、誤象襲之局
，時判局期機表
讓效，提間率示
民等所供，問，
眾方以的若題民
做面，資媒認眾
好，氣料體知對
防加象做之，於
颱強局說氣並颱
準與將明象不風
備媒從，預夠路
。體資很報清徑
人訊容人楚、
員收易員，風
互集讓未颱雨
、
Typhoon Aere visible image,
wind and rainfall forecast
Hurricane Isabel
Synoptic Surveillance
Sept 13 to Sept 17, 2003
Red tracks: AFRES WC-130
Blue tracks: NOAA G-IV 00Z
Green tracks: NOAA G-IV 12Z
TRMM SEES RAIN FROM HURRICANES FALL
AROUND THE WORLD
Since rain and freshwater flooding are the number one causes of death from
hurricanes in the United States over the last 30 years, better understanding of
these storms is vital for insuring public safety. A recent study funded by
NASA and the National Science Foundation offers insight into patterns of
rainfall from tropical storms and hurricanes around the world.
Researchers at the University of Miami's Rosenstiel School of Marine and
Atmospheric Science, Miami, and the National Oceanic and Atmospheric
Administration Atlantic Oceanographic and Meteorological Laboratory's
Hurricane Research Division, Miami, used data from NASA's Tropical
Rainfall Measuring Mission (TRMM) satellite to show how rain falls at
different rates in different areas of a storm. The results were published in the
July issue of the journal Monthly Weather Review.
The results are already being used in a model developed at the Hurricane
Research Division to estimate rainfall accumulation related to tropical
cyclones. The findings are important because they may help in the
development of better forecasts.
US Navy global forecast model output (48hr forecast) Typhoon Aere and Chaba
Dust storm and aerosol- a climate issue
Real time monitoring of North Africa dust storm
The United Arab Emirates Unified Aerosol Experiment mission runs from August 5 through
September 30. Scientists are using satellites, computer models and ground stations to understand
the unique "mixing bowl" of desert dust, smoke and other aerosols created by the complex
atmospheric circulations.
This is a true color image of the United
Arab Emirates taken from Aqua-MODIS
on August 10, 2004. A dust plume
surrounds peninsular UAE/Oman and the
Straight of Hormuz.
Scientists Study Desert Air to Understand
Weather and Climate
NASA, Naval Research Laboratory and Scripps Institution of Oceanography scientists have assembled in the Arabian Desert to study
tiny airborne particles called aerosols and their effect on weather and climate. The scientists are collaborating with researchers
from the United Arab Emirates Department of Water Resources Studies and 20 other U.S., European and South African research
laboratories to decipher the complex processes controlling the area climate.
The United Arab Emirates Unified Aerosol Experiment mission runs from August 5 through September 30. Scientists are using
satellites, computer models and ground stations to understand the unique "mixing bowl" of desert dust, smoke and other aerosols
created by the complex atmospheric circulations.
"Man-made emissions, smoke from the Indian subcontinent and desert dust combine in the air to make a unique aerosol laboratory,"
said Hal Maring of NASA Headquarters, Washington.
"We have the most intensely monitored remote-sensing aerosol network ever assembled, including two radiation and aerosol super
sites, 10 satellite instruments, six computer models, a research aircraft and a research vessel," said Jeff Reid, mission scientist
from the Naval Research Laboratory in Monterey, Calif. "There are 70 scientists participating, 40 of them working in the field,
from over a dozen institutions, including the large South African and Colorado-based National Center for Atmospheric Research
weather modification teams," he added.
Aerosols have always been an interesting puzzle piece in learning how climate works.
Lighter aerosols reflect heat and sunlight and have cooling properties. Darker
aerosols absorb heat and light, warming the atmosphere. This mission will
measure aerosol properties, where aerosols move, and whether they add or
remove warmth. Scientists also hope to model and explain complicated weather
patterns in the coastal regions of the Arabian Gulf and the Gulf of Oman.
By obtaining more accurate data about aerosols and their behavior, scientists will improve computer climate models and predictions of
climate behavior in response to changes in aerosol concentrations. To accomplish this task, NASA will start from space, using
primarily its Terra and Aqua satellites, but other satellites as well. Aboard Terra, the Multi-angle Imaging SpectroRadiometer
instrument, built and managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., will provide an independent measure of
aerosol size and concentration, as well as altitude in some cases. That instrument observes aerosols over both land and ocean.
These satellite data will be compared to ground-based remote sensing measurements of mineral dust and pollutant aerosols gathered
by 15 Aerosol Robotic Network instruments over land and water, the Naval Research Laboratory Mobile Atmospheric
Aerosol and Radiation Characterization Observatory and NASA's Surface-sensing Measurements for Atmospheric Radiative
Transfer.
20世紀氣候學的進步
• 氣候學三個經典概念(1)氣候包括三個要素: (氣)溫，濕(降
水)，(氣)壓; (2)如果有了30年3個基本要素的平均值即可
代表一個地區的氣候; (3)氣候形成的三大要素: 太陽輻射(
地理經緯度)，海陸分布，以及大氣環流。
• 氣候平均值的概念(normal)意指標準。但是氣候變化表示
平均值也在改變。
• 氣候是局部性的？還是全球性的？
• 天氣預測用大氣環流模式，而氣候預測必須用海氣耦合模
式才行。
• 現代氣候學觀點，氣候是全球性的，氣候學研究對象不再
是局地氣候，而是氣候系統（earth climate system）。
20世紀氣候學理論研究的十大成就
 20~30年代, 三大氣壓震盪,北大西洋震盪(NAO),北太平洋
震盪(NPO),南方震盪(SO); Walker (1932)
 30年代, 大氣長波理論-羅士比波, Rossby (1939)
 40~50年代, 時間平均環流之長波預測, Namias (1953)
 60年代, 赤道東西向沃克環流, Bjerknes (1969)
 70年代, 溫室效應(doubling CO2), Manabe (1975)
 80年代, 月平均環流預測, Miyakoda (1986)
 80~90年代, ENSO預測, Cane and Zebiak (1986)
 80~90年代, ENSO理論, Suarez (1988), Battisti (1989)
 90年代, 溫鹽環流, Delworth (1993)
 90年代, 季平均環流預測, Ming Ji (1994)
21世紀的進展：氣候變遷的預測（IPCC-AR4）
全球暖化與
氣候變遷
UK
The contribution to each winter's total precipitation made from "heavy"
precipitation days, indicated by red (below average) and blue (above average)
bars. A black smoothing line to highlight decadal variations has been overlaid.
Decadal annual SST anomalies (°C)
from 30-yr (1961–90) climatology:
from (a) decade of 1891–1900 to (j)
decade of 1981–90
Walker circulation-an equatorial belt circulation
Chervin and Druyan 1984 MWR
Walker’s southern oscillation (Bjerknes 1969)
大氣海洋交互作用-聖嬰與南方震盪ENSO
•
•
•
•
•
•
Journal of the Atmospheric Sciences: Vol. 32, No. 1, pp. 3–15.
The Effects of Doubling the CO2 Concentration on the climate of a General
Circulation Model
Syukuro Manabe and Richard T. Wetherald
Geophysical Fluid Dynamics Laboratory/NOAA, Princeton University, Princeton, N.J.
08540
(Manuscript received 6 June 1974, in final form 8 August 1974)
ABSTRACT
An attempt is made to estimate the temperature changes resulting from doubling the
present CO2 concentration by the use of a simplified three-dimensional general
circulation model. This model contains the following simplications: a limited
computational domain, an idealized topography, no heat transport by ocean currents,
and fixed cloudiness. Despite these limitations, the results from this computation
yield some indication of how the increase of CO2 concentration may affect the
distribution of temperature in the atmosphere. It is shown that the CO2 increase raises
the temperature of the model troposphere, whereas it lowers that of the model
stratosphere. The tropospheric warming is somewhat larger than that expected from a
radiative-convective equilibrium model. In particular, the increase of surface
temperature in higher latitudes is magnified due to the recession of the snow
boundary and the thermal stability of the lower troposphere which limits convective
beating to the lowest layer. It is also shown that the doubling of carbon dioxide
significantly increases the intensity of the hydrologic cycle of the model.
•
•
•
Monthly Weather Review: Vol. 114, No. 12, pp. 2363–2401.
One-Month Forecast Experiments—without Anomaly Boundary Forcings
K. Miyakoda, J. Sirutis, and J. Ploshay
Geophysical Fluid Dynamics Laboratory/N0AA, Princeton University, Princeton, NJ 08542
•
•
•
(Manuscript received 17 August 1985, in final form 19 May 1986)
ABSTRACT
A series of one-month forecasts were carried out for eight January cases, using a particular
prediction model and prescribing climatological sea-surface temperature as the boundary
condition. Each forecast is a stochastic prediction that consists of three individual integrations.
These forecasts start with observed initial conditions derived from datasets of three
meteorological centers. The forecast skill was assessed with respect to time means of variables
based on the ensemble average of three forecasts. The time or space filter is essential to suppress
unpredictable components of atmospheric variabilities and thereby to make an attempt at
extending the limit of predictability. The circulation patterns of the three individual integrations
tend to be similar to each other on the one-month time scale, implying that forecasts for the 10
day (or 20 day) means are not fully stochastic. The overall results indicate that the 10-day mean
height prognoses resemble observations very well in the first ten days, and then start to lose
similarity to real states, and yet there is some recognizable skill in the last ten days of the month.
The main interests in this study are the feasibility of one-month forecasts, the adequacy of initial
conditions produced by a particular data assimilation, and the growth of stochastic uncertainty.
An outstanding problem turns out to be a considerable degree of systematic error included in the
prediction model, which is now known to be “climate drift.” Forecast errors are largely due to
the model's systematic bias. Thus, forecast skill scores are substantially raised if the final
prognoses are adjusted for the model's known climatic drift.
Oscillation of the thermohaline circulation
•
•
•
•
•
•
Journal of Climate: Vol. 6, No. 11, pp. 1993–2011.
Interdecadal Variations of the Thermohaline Circulation in a Coupled
Ocean-Atmosphere Model
T. Delworth, S. Manabe, and R.J. Stouffer
Geophysical Fluid Dynamics Laboratory/N0AA, Princeton University, Princeton,
New Jersey
(Manuscript received 5 September 1992, in final form 26 February 1993)
ABSTRACT
A fully coupled ocean-atmosphere model is shown to have irregular oscillations
of the thermohaline circulation in the North Atlantic Ocean with a time scale of
approximately 50 years. The irregular oscillation appears to be driven by density
anomalies in the sinking region of the thermohaline circulation (approximately
52°N to 72°N) combined with much smaller density anomalies of opposite sign in
the broad, rising region. The spatial pattern of sea surface temperature anomalies
associated with this irregular oscillation bears an encouraging resemblance to a
pattern of observed interdecadal variability in the North Atlantic. The anomalies
of sea surface temperature induce model surface air temperature anomalies over
the northern North Atlantic, Arctic, and northwestern Europe.
http://www.cpc.ncep.noaa.gov/schemm
http://www.emc.ncep.noaa.gov/research/cmb/atm_forecast/images
Multiseason climate forecast with coupled model
•
•
•
Bulletin of the American Meteorological Society: Vol. 75, No. 4, pp. 569–578.
A Multiseason Climate Forecast System at the National Meteorological Center
Ming Ji, Arun Kumar, and Ants Leetmaa
Coupled Model Project, National Meteorological Center, NOAA/NWS, Washington, D.C.
•
•
ABSTRACT
The Coupled Model Project was established at the National Meteorological
Center(NMC)in January l991 to develop a multiseason forecast system based on
coupled ocean atmosphere general circulation models. This provided a focus to combine
expertise in near real-time ocean modeling and analyses situated in the Climate Analysis
Center (CAC) with expertise in atmospheric modeling and data assimilation in the
Development Division. Since the inception of the project, considerable progress has
been made toward establishing a coupled forecast system. A T40 version of NMC's
operational global medium-range forecast model (MRF) has been modified so as to have
improved response to boundary forcing from the Tropics. In extended simulations,
which are forced with observed historical global sea surface temperature (SST) fields,
the model reproduces much of the observed tropical Pacific and North American rainfall
and temperature variability. An ocean reanalysis has been performed for the Pacific
basin starting from July 1982 to present and uses a dynamical model-based as
assimilation system. This also provides the ocean initial conditions for coupled fore cast
experiments. The current coupled forecast model consists of an active Pacific Ocean
model coupled to the T4Oversion of the NMC's MRF. In the future, a global ocean
model will be used to include climato information from other ocean basins. The initial
experiments focused on forecasting Northern Hemisphere winter SST anomalies in the
tropical Pacific with a lead time of two seasons. The coupled model showed
considerable skill during these experiments. Work is currently under way to quantity the
skill in predicting climatic variability over North America.
太陽表面擾動
(左)太陽表面粒斑化特徵圖, 包括太陽黑子[sunspots],光斑
[faculae], 和光焰[flares]。(右)日全蝕下的日冕[corona]。太陽活
耀年時(1958) 太陽表面的黑子、光斑、及光焰數目非常多。反
之，稱為太陽安靜年(1964)。
Between Sun and Earth
Since 1965, the Mauna Loa Solar
Observatory has collected solar data from
Hawaii's second- highest peak. The site
now hosts the Advanced Coronal
Observing System.
This sequence of images
shows the change in
electron densities through
Earth's atmosphere,
primarily in the ionosphere,
during a solar storm on 10
January 1997.
Concluding remarks
• 大氣科學日新月異，由定性走向定量，由區域走
向全球，與社會需求緊密結合，與政策擬定息息
相關，已成為政府決策和大眾生活中不可或缺的
一環。
• 大氣科學學習態度由觀察、瞭解、到實踐，基礎
理論架構的建立不可或缺。堅強的數理基礎是必
要的工具。全球的環境問題由於衛星科技的蓬勃
發展更凸顯大氣科學知識建立的重要性。
NTU/DAS-Atmospheric Sciences 101
Homework #2
2012/9/13
• Reading assignment, P17-26, Weather and climate, storms
of all sizes and weather maps
• P 434, How do hurricanes compare with mid-latitude
cyclones? (wind, pressure, structure, and energy sources)
• Due on 2012/9/25