The 1987 Airborne Experiment - NTRS - NASA

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the Nimbus-7 spacecraft was downlinked to one of NASA's network of spaceflight tracking stations, such as at Wallops. Island,. Goldstone, or Santiago, and then ...
NASA Reference Publication 1201 March

1988

The

1987 Airborne

Antarctic

Ozone

Experiment The Nimbus-7

TOMS

Data Atlas

Arlin J. Krueger, Philip E. Ardanuy, Frank S. Sechrist, Lanning M. Penn, David E. Larko, Scott D. Doiron, and Reginald N. Galimore _J_5-,_C714 _]tA5

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NASA Reference Publication 1201 1988

The

1987 Airborne

Antarctic

Ozone

Experiment The Nimbus-7

Arlin

Data

J. Krueger

Goddard Space Flight Greenbelt, Maryland

Philip Frank

TOMS

Center

E. Ardanuy, S. Sechrist,

Lanning M. Penn, and David E. Larko Research and Data Systems Corporation Lanham, Maryland Scott and

D. Doiron Reginald

Science Applications Lanham, Maryland

National Aeronautics and Space Administration Scientific and Technical Information Division

N. Galimore Research

Corporation

Atlas

THE

1987

AIRBORNE THE

ANTARCTIC

NIMBUS-7

OZONE

TOMS

Table

DATA

EXPERIMENT:

ATLAS

of Contents

Pa e

Section

INTRODUCTION

........................

1.1

The

1987 Airborne

1.2

The

Nimbus-7

TOMS

DATA

2.1

Data

Antarctic

2.2

The

Near-Real

2.3

Data

Analysis

TOMS

TOTAL

3.1

Chronology

of the

3.2

Latitudinal

Cross-Sections

3.3

Time

at Locations

3.4

Near-Real

3.5

Southern

Hemispheric

3.6

Mapping

Onto

TOMS

Time

OZONE

Series

AND

to Punta

and

Time

4

REFERENCES

5

ACKNOWLEDGEMENTS

Ozone

Experiment

PREPARATION

Available

1

Experiment

Arenas

..........

...............

3 Network

.......

3 7

..................

13

................

13

.................. of Interest Charts Polar

..............

21

..............

Charts

Flight

18

Paths

39

..............

93

.............

.........................

PRECEDING

3

...............

Experiment

Aircraft

1

TRANSFER

Presentation

Orbital

1

..............

Telecommunications

DATA

........

243

.....................

PAGE

216

BLANK

245

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iii

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1.

INTRODUCTION

Both ground-based (Farman et al., 1985) and satellite (Stolarski et al., 1986; Schoeberl and Krueger, 1986; Krueger et al., 1987) observations have documented a startling downward trend the total column ozone amounts over Antarctica. This decrease, which occurs seasonally during

in

September and October, has resulted in a depletion in the column ozone amounts by as much as 50%. The Antarctic ozone minimum, termed "the ozone hole," reached the lowest values ever observed in 1987. Several theories have been advanced to explain the loss of the ozone over Antarctica and the formation of the ozone hole. These include the effects on the total column ozone abundance due to climatic variability and changes in the stratospheric circulation patterns (Newman and Schoeberl, 1986; Chandra and McPeters, 1986), interactions with the 11-year solar sunspot cycle (Callis and Natarajan, 1986), and chemical reactions with enhanced levels of chlorine monoxide (possibly caused by the introduction of chlorofluorocarbons into the atmosphere) (Farman et al., 1985). Observations from the Satellite Aerosol Measurement (SAM II) instrument (McCormick and Trepte, 1986) and the Limb Infrared Monitor of the Stratosphere (LIMS) instrument (Austin et al., 1986) on board the Nimbus-7 spacecraft have revealed the presence of Antarctic Polar Stratospheric Clouds (PSC's). These PSC's are present in the Antarctic lower stratosphere with cloud tops of from 15 to over 20 km throughout September. It has been suggested that heterogeneous reactions on the surface of the cloud particles may be related to the formation of the ozone hole (Toon et al., 1986; Crutzen et al., 1986).

1.1

The

1987

Airborne

Antarctic

Ozone

Experiment

The goal of the 1987 Airborne Antarctic Ozone Experiment was to improve the understanding of the mechanisms involved in the formation of the Antarctic ozone hole. The campaign was conducted during the period between August 8, when the mission go/no-go criteria were satisfied, and September 29, when the last Antarctic flight was conducted. This duration permitted a sampling of the preconditions to the formation of the ozone hole, as well as the opportunity to directly observe the onset and intensification of the ozone hole as it evolved during the field experiment. During the experiment, two specially instrumented NASA research aircraft were based in Punta Arenas, Chile. These aircraft flew into and below the ozone hole to make in situ and remotely sensed observations of the atmospheric chemistry and thermodynamic structure. Excluding the transfer flights to and from Punta Arenas, the ER-2 aircraft made 12 flights from Punta Arenas along the Palmer Peninsula at altitudes of from 12 to 19 km, while the DC-8 made 13 long-range flights at lower altitudes of 13 kilometers and below. The Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) played a central role in the experiment by supplying timely maps of the total ozone distribution over the southern hemisphere. These data were made available to the experiment in a near-real time mode and thus were useful in directing the aircraft by providing the locations of the ozone hole boundary, and in project planning activities in general. TOMS data coverage over several orbital segments centered about the Palmer Peninsula was supplied within several hours of real time, and TOMS data coverage over the entire southern hemisphere was supplied within a day of real time.

1.2

The

Nimbus-7

TOMS

Experiment

On October 24, 1978, the Nimbus-7 spacecraft was launched into a local-noon, sun-synchronous, near-polar orbit. The satellite has provided a measuring platform for eight different experiments and instruments which have observed the Earth's surface, atmosphere, and oceans, and the Sun, in the ultraviolet, visible, near-infrared, infrared, and microwave regions of the spectrum. The TOMS experiment on board Nimbus-7 continues to take high quality data at this time, after more than 9 years of operation.

The TOMS has a 3° by 3° instantaneousfield of view (IFOV), with a ground resolution of 50 km at the subsatellite point. The TOMS radiancesare sampledin 3° steps+51 ° from nadir across the ground track, yielding a total of 35 samples every 8 seconds (Heath et al., 1978). With the 104-minute orbital period of the Nimbus-7, the 8-second scan cycle means that successive scan lines are displaced a little less than 0.5 ° , or about 50 km, along the orbital track. Due to the Earth's rotation, each orbit of data taken by the Nimbus-7 satellite is located approximately 26 ° of longitude west of the preceding orbits. At the 51 ° extreme scan position, the field of view extends to slightly over 13 ° of the Earth central angle from nadir. Thus, there is no data void between orbits, even at the equator, and true global total ozone mapping is assured. The TOMS is a single Ebert-Fastie spectrometer, and measures reflected shortwave radiation at six wavelengths ranging from 0.312tsm to 0.380gm for each sample. The total ozone retrieval algorithm is based on a technique measuring the backscattered ultraviolet radiation (Dave and Mateer, 1967), and closely follows the Nimbus-4 BUV total ozone algorithm (Mateer et al., 1971; Klenk et al., 1982). The measured intensities at the satellite are the sum of both the atmospheric backscattered radiation and the surface-reflected direct and diffuse contributions. The term involving the surface-reflected ultraviolet component is dependent on the atmospheric transmission, itself a function of the ozone optical depth along the slant path of the radiometer's field of view. The two longest wavelengths, which are outside the ozone absorption band and have centers at 0.360 p.m and 0.380 gm, are used to determine the surface reflectance. Given the surface reflectance, the total column amount of ozone is computed from radiances observed with the four shortest wavelengths (0.313 tsrn, 0.318 #m, 0.331/_m, and 0.340 ktm ) through a table lookup and interpolation procedure (Fleig et al., 1982). The backscattered ultraviolet radiances are inverted to yield total ozone up to a solar zenith angle of 88 ° . No nighttime total ozone observations are taken. Thus, the only areas of the Earth for which total ozone measurements are not recovered are in the winter polar regions during 24-hour night.

2.

TOMS

DATA

PREPARATION

AND

TRANSFER

The near-real-time processing and transfer of TOMS ozone data commenced on August 8, 1987 and concluded on September 29, 1987. The processing involved two data sets: (1) complete southern hemispheric data for the 24 hours ending at midnight of the day prior to transmission and (2) orbital swath data for the region including and adjacent to Punta Arenas, Chile, and the Palmer Peninsula of Antarctica processed the same day it was observed.

2.1

Data

Available

to Punta

Arenas

The orbital swath data consisted of 2 to 3 orbits daily, which were processed and transferred to Punta Arenas as they were received. Selection of the particular orbits was effected well in advance through the use of predictive ephemeris to generate tables of the orbital ascending-node times and longitudes and plots of the orbital subsatellite tracks (Figure 1). The real-time data flow and transfer is illustrated in Figure 2. Telemetry from the Nimbus-7 spacecraft was downlinked to one of NASA's network of spaceflight tracking stations, such as at Wallops Island, Goldstone, or Santiago, and then transmitted over the NASA Deep-Space Network to the Goddard Space Flight Center (GSFC). The raw TOMS data from each orbit were received at the Mission Operations Control Center (MOCC) in Building 3 at the GSFC and placed onto magnetic tape. This tape was then manually transferred to the NASA Space and Earth Sciences Computing Center (NSESCC) in Building 1 at the GSFC where the raw data were processed into total ozone and reflectivity data on an IBM 3081 computer in Ozone-T standard tape format. The ozone data were copied to the dedicated TOMS MicroVAX II computer in Building 21 at the GSFC via a fiber optics Ethernet connection. At this point, the orbital swath data were processed prior to release to Punta Arenas. This processing included the gridding of the calibrated Ozone-T data to create an image file, with further processing to display the image file. Once the image was viewed and deemed acceptable, the Ozone-T data files, one for each of up to three orbital swaths, were then transferred via DECnet and two Racal-Milgo 9632 forward error-checking modems at 9.6 kilobits/second (kbps) to a second MicroVAX II located in Punta Arenas. The orbital-swath processing required approximately 30 minutes. The total elapsed time between the actual Nimbus-7 pass over the orbital area and the receipt of total ozone data in Punta Arenas varied between 3 and 4 hours. Once received at Punta Arenas (and at GSFC as well), the data were plotted both in contour form using GEMPAK, as shown here, and in color using a Tektronix 4692 plotter and 4208 color graphics terminal and a standardized color look-up table. The color plots facilitated comparison and permitted rapid interpretation day-to-day changes in the ozone pattern.

of

The hemispheric data were processed in a similar fashion, but the elapsed time was greater. A full duration of 24 hours is required for the Nimbus-7 TOMS to obtain global (or southern hemispheric) coverage. The hemispheric data set, containing total ozone data from a complete day of Nimbus-7 orbits, was available to the TOMS MicroVAX by approximately noon of the following day, or 12 hours after Nimbus-7 completed its last orbit of the day. This data set was gridded on the IBM 3081 in Grid-T format and required minimal further processing prior to transfer. The hemispheric ozone data were also transferred to the Punta Arenas MicroVAX II via a DECnet link.

2.2

The

Near-Real

Time

Telecommunications

Network

To support the voice, facsimile, and digital data telecommunications requirements of the 1987 Antarctic Airborne Ozone experiment, a tri-continental network of dedicated lines and associated signal processing equipment was designed, installed, and operated during the experiment by Research and Data Systems (RDS) Corporation. The network design is illustrated in Figure 3. The telecommunications network configuration permitted meteorological forecast and analysis

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Punta Arenas, Chile Real-Time MioroVAX II TOMS Project

Data

Flow

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During

the

1987 Airborne

Antarctic

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facsimile maps to be supplied to the operations centers at the NASA/GSFC and in Punta Arenas, Chile. Both the European Centre for Medium-Range Weather Forecasting (ECMWF) and the United Kingdom Meteorological Office (UKMO) supplied meteorological products in support of the experiment. The network also permitted general voice and facsimile communications between the Punta Arenas Communications Center, Europe (via the ECMWF and UKMO exchanges), ancl the United States (via the GSCF CBX-9000 exchange), and voice-only communications to Palmer Station in Antarctica (via the INMARSAT gateway). A more complete discussion of the telecommunications network may be found in Ardanuy et al. (1987). As shown in Figure 2, the TOMS total ozone data sets were transferred to the MicroVAX II in Punta Arenas via the above-stated network using the DECnet protocol. Because of the dedicated nature of the lines, the high data rate (9.6 kbps), the 24-hour manning of the communications center in Punta Arenas, and the extremely reliable operation of the network as a whole, the TOMS data sets were routinely transferred to the investigators in Punta Arenas in an extremely timely manner. The near-real time orbital total ozone data and delayed hemispheric data were thus of the highest utility in directing the ER-2 and DC-8 aircraft by providing the locations of the ozone hole boundary and navigational information for the mission. The data sets also were used to support the project planning activities in general. The ability of the network to provide numerical weather prediction charts to the mission forecaster and to provide TOMS total ozone data to the operations center in Punta Arenas were critical to the success of the compaign and were designated go/no-go criteria for the release of the research aircraft from the NASA/Ames Research Center. In view of the desired August 17 beginning of the experimental flight period, the project's go/no-go decision date was set at August 8. The mission criteria were satisfied on August 8 as required, and the DC-8 and ER-2 aircraft left NASA/Ames to fly to Punta Arenas.

2.3

Data

Analysis

and

Presentation

Raw TOMS data are converted into total ozone estimates and Earth-located, after which the ungridded TOMS measurements are archived on the Ozone-T tape product. When gridded, the TOMS total ozone observations are stored on the GRIDTOMS archival tape product. During the experiment, the Ozone-T processing was conducted as soon as each orbit within the domain of interest was received at GSFC, while the GRIDTOMS processing was performed once per day on the most recent 24 hours of data. Thus, the orbital swath data were derived from the Ozone-T data sets, while the hemispheric charts were based on data from the GRIDTOMS data sets. During the experiment, the near-real-time processing was accomplished by accessing the respective data sets, which resided in disk storage on the IBM 3081 in "virtual magnetic tape" format. Data on the GRIDTOMS tapes (Nimbus, 1986) are organized into one-degree latitude zones. The latitude zones are subdivided into cells, each of which contain total ozone values and related parameters and cover the entire globe. As the poles are approached and the distance around the globe along a latitude circle diminishes, the orbits overlap. The number of cells in a zone, in turn, will vary from 288 at the equator to 72 at the poles. The longitudinal resolution of the cellular total ozone values thus varies from 1.25 ° between 50°N and 50°S latitude, to 10 ° poleward of the 80 ° latitudes. The cells contain total ozone estimates which are taken from that satellite orbit closest to the center of each cell. These estimates correspond to the Samples nearest the 18th (nadir) scan position. In the latitude zones poleward of 50 ° the tape also contains, depending on the latitude, up to seven additional total ozone estimates which are obtained from the next closest orbits. Of course, these alternative estimates possess local times which are separated by 104-minute orbital period increments from the total ozone estimate taken .' at the closest approach. Only the total ozone measurements from the closest satellite overpass fire considered here. This selection is performed for two reasons: first, the most vertical glimpse and the smallest footprint is obtained, and second, time-averaging of the ozone field is avoided. After extraction from tape, poleward of the 50 ° latitudes, the TOMS data are initially

repeatedat

the globally uniform longitudinal resolution of 1.25 °. The data are next reduced to a global array with a uniform resolution of 5 ° of longitude by 2 ° of latitude. This is accomplished by producing a weighted average of the larger array for each element, i.e., two by four observations. The averaging scheme uses the following set of weights:

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The weighting is adjusted if values are missing from the 2 by 4 element box. If five or more values are missing, then the weighted value is also recorded as missing. The total ozone values at the poles are computed by averaging all the cells between 89 ° and 90 ° . The hemispheric plots presented in this atlas consist of a subset of this 91 by 72 element array located between 10 ° and 90 ° south latitude. The plots were produced using an interactive data analysis and graphics package, termed GEMPAK (desJardins and Petersen, 1985). GEMPAK requires input d_ to be gridded onto a uniform latitude/longitude grid. Since these data are now in such a format, no further processing is required prior to plotting. The advantages of using the reduced resolution data set are that all small data gaps are eliminated and the synoptic and planetaryscale features are clearly displayed. The disadvantage is that any mesoscale features present in the unfiltered TOMS data are eliminated. The orbital total ozone data, tagged by the latitude and longitude of the IFOV center point, along with several other products, were extracted from the Ozone-T data set (Fleig et al., 1982) for the southern-hemisphere analysis domain and processed using GEMPAK. Because of storage limitations imposed by GEMPAK, measurements from every third scan line, and every third observation in that scan line, were extracted from the orbital swath data. The selected observations for each day were objectively analyzed within GEMPAK using two passes through Barnes objective analysis routine. The grid spacing produced was 2° in latitude and 1.5 ° in longitude. Because of the excellent signal-to-noise characteristics of the TOMS total ozone data, the numerical convergence parameter (Koch et al., 1983) was set at 0.3, yielding a minimur of additional smoothing and the greatest detail in the final analysis. Figure 4 depicts a small portion of a single orbital swath from August 17, 1987 displaying digitally the ozone values prio to objective analysis. This orbit (number 44500) is the first of two orbits of Earth-located total ozone observations used to compose the objectively analyzed near-real-time ozone field for the day. The satellite track is from the bottom to the top of the figure, with each cross-track scan sweeping from right to left across the track. The data are unevenly distributed, with the greatest density of observations occurring near nadir (right), and the least out towards the Earth's limb (left). Figure 5 depicts the same area after the data have been objectively analyzed onto a uniform grid as described above. A more uniform density of total ozone value., has been achieved. A minimum of 172 DU is achieved midway up the eastern coast of the Antarctic Peninsula, with a strong gradient to the west, north, and south. Comparing the analysis to the original data, we find good agreement. At the eastern base of the peninsula, an analyzed value of 235 DU compares well to the pre-analysis magnitude of 237 DU. At the tip ( the peninsula, an analyzed magnitude of 230 DU is in good agreement with the 231 DU observ_ tion. However, slight differences are apparent. For example, the minimum value Of the ungridded data from orbit 44500 is 161 DU at about 70°S, compared to 172 DU in the analysis. There are three reasons for this sort of discrepancy: (1) two orbits of data (44500-1) are used in the final analysis and, due in part to temporal variability, overlapping data from neighborin orbits are not perfectly in agreement; (2) a subset of the complete set of measurements are used, though in the objective analysis routine a measurement as low as 162 DU is retained fron orbit 44501 (not shown); and (3) the Barnes scheme filters all high frequency modes with wavelengths close to and smaller than twice the average separation between nearest observations. Clearly, the final analysis of the total ozone distribution (see the August 17 map of Section 3.4) is faithful to the structure and magnitude of the original set of observations (Figure 4).

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A set of daily TOMS total ozone estimates for the southern hemisphere, over the period August 1 through November 30, 1987, are presented here. The daily data are resolved on a uniform 2° latitude by 5 ° longitude grid for each day, and displayed using a south-polar orthographic projection. The advantage of this projection is that emphasis is placed over precisely those highlatitude regions of interest to the Antarctic experiment.

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Flight

Paths

In this section, we relate the distribution of the TOMS total-ozone to the flight paths of the NASA ER-2 and DC-8 research aircraft for their missions during the 1987 Airborne Antarctic Ozone Experiment. The flights were previously tabulated in the chronology. In each figure, the upper panel gives the reader an idea of the flight path of each aircraft mission as projected onto a polar plot, while the bottom panel evaluates the TOMS total-ozone estimates along each flight track. While the abscissa of the bottom panel is time, the reader should be cautioned that the TOMS instrument is carried on board the Nimbus-7 satellite which is sun-synchronous. As such, there is no temporal evolution of the TOMS ozone values during the course of the mission. However, these maps clearly indicate the position of the ozone hole and its boundary relative to each research flight. Though the NASA ER-2 left Ames Research Center on August 12, it did not fly its first mission out of Punta Arenas, Chile for the experiment until August 17. Here we do not consider the three transfer flights (i, ii, and iii) and just illustrate data for the twelve ER-2 missions between the period August 17 and September 22 (Figure 8a-81). Similarly, we do not consider the two DC-8 flights between NASA Ames and Punta Arenas between the period August 19 and August 22 Data for the thirteen DC-8 missions during the experiment is illustrated in Figure 9a-9m, and includes the final flight between Punta Arenas, Chile and Christchurch, New Zealand.

216

AUG

20_ A L T 18 _ I T U 10 D E B K M 0 BOO00

350 T 0 M 300 S

17

ER2

LAT

°'''"

"-.°

°o,O_'°'°°''"

the

T

-60

A N D

0 N G

8BO00

60000 FLIGHT TIME

B8000 IN GMT SECONDS

17

AUG

_

-75 78000

70000

ER2

_ "-.°.'-----._°

__

....

...----'--

......

-

-°._.---

_° .° .-_----.___.-_-

I 55000

180 80000

8a.

-85

-70

'''-°----__.

projection

.o

L A

-68

0 280 Z 0 N _00 E

Figure

....

-80

Flight (top)

corresponding

Path and

as TOMS

of

1 B0000 FLIGHT TIME

the

a time

ER-2 series

total-ozone

I 65000 IN GMT SECONDS

mission of

latitude,

estimates

for

August

17

longitude, along

1 70000

the

as and

flight

I 75000

mapped altitude path

onto

a polar

along

with

(bottom).

217

25

AUG

_ LAT

18

ER2

_-50

A L 20 T I TI5 U

_ -88



_-60

D I0 E

_ -85

K M

_-70

5 0 kT.T 80000

[

85000

I 60000 FLIGHT TIME

AUG

350 _ T 0 M 300 S

I 88000 IN GMT SECONDS

18

---

0 250 Z 0 H 200 _ E

-75 )00

) 75000

_

-

.-° °_°-..

I 55000

._--'"

l 50000 FLIGHT TIME

Figure 8b. Flight Path of the ER-2 projection (top) and as a time series the corresponding TOMS total-ozone

218

) 70000

L 0 N G

°..--.-.. -

150 50000

78

A N D

ER2

°._'°° -.-__....

I 70000

L A T

J 05000 IN GMT SECONDS

mission for August 18 as mapped onto a polar of latitude, longitude, and altitude along with estimates along the flight path (bottom).

S8 A L SO T I T 18 U

LAT

AUG

23

ER2

-80 -SB

L A T

-60

A

-66

N D

-70 -78 K M

-80 O/ 60000

350 T 0 M 300 S

I 58000

1 BOO00 FLIGHT TIME

AUG _- .....

°..

I 6BO00 IN GMT SECONDS

23

-88 75000

. .°-°-.

.__..

-..°°

N G

ER2

..°---'--

---

I 70000

L O

---

....

..

°_

-_

--.°

.° --.

°° °

0 SS0 Z O. N S00 E 180 80000

. --

-

.

°-_-_-

I B8000

I 60000 FLIGHT TIME

Figure 8c. Flight Path of the ER-2 projection (top) and as a time series the corresponding TOMS total-ozone

IN

I 6BOO0 GMT SECONDS

I 70000

I 78000

mission for August 23 as mapped onto a polar of latitude, longitude, and altitude along with estimates along the flight path (bottom).

219

SO_ A L T 18 I T U I0 D g 8 K M 0 48000

LAT

AUG 28

-50 -85 -60 -68

-?8 -80 80000

88000 FLIGHT

80000 TIME IN GHT

86000 SECONDS

70000

-85 ?8000

ER2

------°.° _.-_o

MO300 B

_-° -_

o S80 z O. g 200 1501 48000

_..--

--_° -.o-

J 80000

J 88000 FLIGHT

Figure 8d. Flight Path of the ER-2 projection (top) and as a time series the corresponding TOMS total-ozone

220

L A T A N D

-?0

AUG 28 T 380 I

ER2

I 60000 TIME IN GMT

I 68000 SECONDS

J 70000

I "8000

mission for August 28 as mapped onto a polar of latitude, longitude, and altitude along with estimates along the flight path (bottom).

L 0 N G

• b, F,.-,,,_

RP

II.ol

80 A L T 15 l T U D E

LAT

AUG

30

ER2

-80

'2

-55

L A T

-60

A

-55

N D

-?0 -?5

K M

-80 O! 45000

350 T 0 M 300 8

N G

-88 50000

55000 FLIGHT

60000 TIME IN GMT

AUG

30

55000 SECONDS

70000

78000

ER2

-m..

-_.

__.-°

°. .-

-.

0 SS0 Z 0 N a00 E 1O0 45000

L 0

..-'" -°-_.__

...._-°--°

.-°°-----.._

I 80000

I 55000 FLIGHT

_..._°-----

I 60000 TIME IN

GMT

I 55000 SECONDS

t 70000

I 78000

Figure 8e. Flight Path of the ER-2 mission for August 30 as mapped onto a polar projection (top) and as a time series of latitude, longitude, and altitude along with the corresponding TOMS total-ozone estimates along the flight path (bottom). 221

• 0 /,,AT A L T 15 I T U 10 D E 6 K M 0 B0000

380

SEP

2

ER2

-80 -55 -60 -66 -70 -78

58000

60000 FLIGHT TIME

SEP

_

IN

2

66000 GMT SECONDS

70000

-80 75000

I 70000

I 78000

L A T A N D L 0 N G

ER2

T 0

....

-'-

M 300 _.°_. _

0 260 Z 0 N 200 E 150 60000

I 55000

.

I 60000 FLIGHT TIME

Figure 8f. Flight Path of the ER-2 projection (top) and as a time series the corresponding TOMS total-ozone

222

I 65000 IN GMT SECONDS

mission for September 2 as mapped onto a polar of latitude, longitude, and altitude along with estimates along the flight path (bottom).

20_ A L T 18 _ I T U 10: D B 8 K M 0 48000

SEP 4

LAT

-50

-55

-60

A N D

-70

L 0 N 0

-78

80000

55000 FLIGHT

50000 TIME IN GMT

SEP 4

05000 SECONDS

70000

75000

ERa

wu---_.

_----._. -_.°

.°.°-_..

.-

-

_-'-_

_°-"°

_ -

0 280 _ Z 0. J200 _ B 180 48000

L ^ T

-85

580 _ T 0 M 800 _ B

ER2

--

--

.-.

I 80000

I 88000 FLIGHT

-

I I 60000 66000 TIME IN GMT SECONDS

I 70000

I 75000

Figure 8g. Flight Path of the ER-2 mission for September 4 as mapped onto a polar projection (top) and as a time series of latitude, longitude, and altitude along with the corresponding TOMS total-ozone estimates along the flight path (bottom).

223

88 A L 8O T I T U D 10 !1

SEP

LAT

224

T

-80

A N D L 0 N G

I 88000 FLIGHT

80000

I 60000 TIME IN

SEP

9

I 68000 SECONDS

GMT

-78 78000

70000

ER2

_._

.

.-

.---'--.___--._.-

_-

"°.

_

160 48000

8h.

I 80000

Flight

projection the

-88

-70

-.

with

L A

-68

860 T 0 M 800 S 0 860 Z 0 N _00 Z

-80

o o

0 48000

polar

ER2

8

K M

Figure

9

Path (top)

corresponding

I 68000 FLIGHT

of and

the as

TOMS

ER-2 a time

I 80000 TIME IN GMT

mission series

total-ozone

for of

September

latitude,

estimates

I 68000 SECONDS

I 70000

9 as

mapped

longitude, along

the

I 78000

and flight

onto altitude path

a along

(bottom).

SEP

16

ER2

_ -50

L A

L 2O T I T IB U

_ -55

T

-80

A N D

D 10 E

-B5

K M

-70

28

LAT

A

8 i 85000 FLIGHT

liT 80000

0 48000

I BOO00 TIME IN GMT

SEP

38O T 0 M 300 8

with

8i.

__.--

_-

-._

the

_° -.

I 80000

Flight

Path (top)

corresponding

-75 75000

_--°-.

projection

\

ERR

-____

180 48[ 100

polar

I 70000

_-_..

0 880 Z 0 N iO0 E •

Figure

16

I 65000 SECONDS

L 0 N G

I 8B000 FLIGHT

I 60000 TIME IN GMT

of

the

ER-2

mission

and

as

a time

series

TOMS

°

total-ozone

for of

September

latitude,

estimates

I 65000 SECONDS

I 70000

16

as

mapped

longitude, along

the

I 78000

and flight

onto altitude

path

a along

(bottom).

225

SEP 25 A L 20 T I T 15 U D 10 E K M

20

ER2

-50

LAT -85

L A T

"''..

-60

A N D

-65 I

-70

5

L 0 N G

0 45000

I 58000 FLIGHT

i_X.? 50000

I 50000 TIME IN

SEP 350

GMT

20

-75 V5000

I VO000

58000 SECONDS

ER2

_

T 0 M 300 S

N .---

-----.

_

-

..---"

. _.° -_ ......

0 250 Z 0 NSO0 E 150 48000

4.

....

_.. °-..

I 50000

I 86000 FLIGHT

-

_

._--

I 60000 TIME IN GMT

I 66000 SECONDS

I V0000

I 75000

Figure 8j. Flight Path of the ER-2 mission for September 20 as mapped onto a polar projection (top) and as a time series of latitude, longitude, and altitude along with the corresponding TOMS total-ozone estimates along the flight path (bottom).

226

SEP 26 A L 20 T I T U D 10 E 8 K 18 M 0 48000

21

ER2

LAT

-50

"'"..,

-68 -60 "

-'''''

"'"-,

80000

I 88000 FLIGHT

-70 1 60000 TIME IN

SEP

380 T 0 M 300 S ._.

A N D

-68 ".

0NG-_

L A T

21

GMT

I 66000 SECONDS

I 70000

-78 78000

I 65000 SECONDS

I 70000

I 78000

L 0 N O

ER2

-_-.

0 280 Z 0 N 200 E 180 48000

°.

I B0000

I 65000 FLIGHT

I 60000 TIME IN

GMT

Figure 8k. Flight Path of the ER-2 mission for September 21 as mapped onto a polar projection (top) and as a time series of latitude, longitude, and altitude along with the corresponding TOMS total-ozone estimates along the flight path (bottom).

227

_5 A L 20 T I T 15 U D 10 E K M

_

SEP

22

ER2

-80

L A

_

-85

T

_

-60

A N D

_

-65

LAT

8 _ 0 48000

-70

80000

88000 FLIGHT

80000 TIME IN

SEP

380 T 0 M 300 S

22

GMT

68000 SECONDS

?0000

-78 _8000

I 70000

I 75000

L 0 N O

ER2

°----__

.°._"-°_.

0 SS0 Z 0 _

_oo

Z -°.._

E 180 45000

I 80000

I 68000 FLIGHT

I 60000 TIME IN

GMT

I 66000 SECONDS

Figure 81. Flight Path of the ER-2 mission for September 22 as mapped onto a polar projection (top) and as a time series of latitude, longitude, and altitude along with the corresponding TOMS total-ozone estimates along the flight path (bottom). 228

AUG

12

"

A L 10 T I 8 T U 8 D E 4

28

DC8

-50

ALT

L A T

-60

A N D

-70 -80

L 0 N O

-90

K 14 0

I 20

I 40 ELAPSED

380

I 60 TIME

FLIGHT

AUG

_

I 80 (8 MINUTE

28

-100

I 100 INTERVALS)

120

DC8 -_. °

0

"

14 300 S

_

0 280 Z 0 N 200 R

_

..-

"_--°

°°-"-.

°-_

_- ....... "-.._

_

180

I 20

0

ELAPSED

Figure

9a.

projection corresponding

°°----°---

_°.°_°°-

Flight (top)

Path and

TOMS

of

as

the

a time

total-ozone

I 40 FLIGHT

I 60 TI14E

DC-8

mission

series

of

estimates

i 80 (8 14INUTE

for

latitude, along

August

I I00 INTERVALS)

28

as

longitude,

and

the

path

flight

I 120

mapped altitude

onto along

a polar with

the

(bottom).

229

12

AUG

A L 10

TI

30

DC8

-20

AL

-30

\

8

-40 ^

T -._,AT --

-60

D L 0

E

4

-70

K M

a

-80

-""

20

40 ELAPSED

60 FLIGHT TIME

AUG

0 280 Z 0 N 200 E

9b.

corresponding

30

_90 MINUTE

INTERVALS)

DC8

--__ _

_

_°-

_..-----

-

I 2O

0

projection

80 (8

N O

_--

160

230

N

6

360. T 0 M 300 S

Figure

-80

UD

0 0

L A T

Flight (top)

Path and

TOMS

I 40 ELAPSED

of

as

the

a time

total-ozone

I 60 FLIGHT TIME

DC-8

mission

series

of

estimates

I 80 (8

for

latitude, along

I I 100 120 MINUTE INTERVALS)

August

30

as

longitude,

and

the

path

flight

mapped altitude (bottom).

I 140

onto along

a polar with

the

SEP

12 A L 10 T I 8 T U 6 D E 4 K M

/

_

DC8

0

A

-20

N D T

20 -40

..._.? ,,.._

"

, ........

o''°°°''

0

I •0

I 40 ELAPSED

I 60 FLIGHT TIME

SEP

2

I 80 (6

._ -60

t

.........

_°''°-....

0

0 280 Z 0 N 200 E

L

ALT

2

380 T 0 M 300 S

40

I I 100 120 MINUTE INTERVALS)

-80

L 0 N G

-100

140

DC8

B--. -

-

-_.--

_

180 0

I 20

I 40 ELAPSED

I 60 FLIGHT TIME

I 80 (6

I 100 MINUTE

I 120 INTERVALS)

Figure 9c. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight

I 140

2 as mapped onto a polar and altitude along with the path (bottom). 231

SEP

12 A L 10 T I 8 T U 6 D E 4

5

DC8

_ -20 -30 -40 -60

2

"'''''..

[ 20

0

I 40 ELAPSED

.....

I 60 FLIGHT

0 280 Z 0 N _00 E

.o.-'''°°°

TIME

SEP 380 T 0 M 300 S

-?0

L 0

-80

N G

8

I 80 (5

I 100

I 120 INTERVALS)

-90 140

I 100

I 120 INTERVALS)

I 140

MINUTE

DC8

_

-

180 0

I 20

I 40 ELAPSED

I 60 FLIGHT

TIME

I Q0 (5

MINUTE

Figure 9d. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight 232

A N D

-60

".°

K M

L A T

5 as mapped onto a polar and altitude along with the path (bottom).

1_

SEP

L 10 I

"" x-a_ALT

8

8

DC8

-80

/

""

"'"..

-88 -60

.-'""

-68 U D

6

L A T

'"

A N D

-?0 -?0 -80

0

20

40 ELAPSED

60 FLIGHT TIME

SEP

BIBO _

8

80 100 120 (8 MINUTE INTERVALS)

L O N O

-88 40

DC8

T 0 _._ M BOO_ S 0 280_ Z 0 N 200_ E

°

--.

I00 0

I 20

_

I 40 ELAPSED

i 60 FLIGHT TIME

I 80 (8

-

l l 100 120 MINUTE INTERVALS)

Figure 9e. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight

l 140

8 as mapped onto a polar and altitude along with the path (bottom). 233

SEPT

12 A L 10 T I 8 T U 6 D • 4 K M

DC8

_ 40 _ 20 _ 0

A N D

-20

/

-40 L 0 N G

-60

_I

+....

o --

0

ALT

...................

o°-

-80

..+-

I 80

0

ELASPED

360 T 0 M 300 8

II

SEPT

_

I 100 FLIGHT

I1

I 180

i-lO0 2O0

[ 150

I 200

TIME

DC8

0 260 Z 0 N 200 g 180

l 60

0

ELASPED

Figure

9f.

projection corresponding

234

Flight (top)

Path and TOMS

of

as

the

a time

total-ozone

DC-8

mission

series

of

estimates

I I00 FLIGHT

for

latitude, along

TIME

September

11

longitude,

and

the

flight

path

as

mapped altitude (bottom).

onto along

a polar with

the

/

SEP

14 A L 1_

14

DC8

20 0

T 10 I T 8 U D 6 E 4 K M

-20 -40 -60

2

-80

0

I _0

0

380 T 0 M 300 S

I 40 ELAPSED

--

corresponding

TIME

14

-100 140

DC8

°

_.. -._

I 20

0

9g.

I I I 80 100 120 (6 MINUTE INTERVALS)

L 0 N O

°

180

projection

I 60 FLIGHT

SEP

0 280 Z 0 N S00 E

Figure

L A T

/%

Flight (top)

I 40 ELAPSED

Path and

TOMS

of

as

---

.--

.-

the

a time

total-ozone

I 60 FLIGHT

TIME

DC-8

mission

series

of

estimates

I 80 (8

for

latitude, along

I lO0

I 12Q

MI, ' E IHTEeVALS September

14

longitude,

and

the

path

flight

as

mapped altitude

I 140

onto along

a polar with

the

(bottom).

235

SEP

14 A L 1Q

16

DC8

-80

'3-60

T 10

-70

g, I

4

I" 0

I SO

0

350

_

0 M 300' S

_

I 40 ELAPSED FLIGHT

8EP

I 60 TIME

16

I 80 MINUTB

(5

I 100 INTERVALS)

L A T

-80

A N D

-90

0L

-100

N O

-110 1 S0

DC8

T -'_" .

°_--__'° _-

0 2O0 Z 0 N 200 e



.

.°°"

_

-._

-o "--_

.._° -.__.-

150 0

I 20

I 40 ELAPSED FLIGHT

I 60 TIME

I 80 (5 MINUTE

I 100 INTERVALS)

Figure 9h. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight i36

I 120

16 as mapped onto a polar and altitude along with the path (bottom).

SEP

14

19

DC8

-40

A L 12

-50

T 10 I T 8 U D 6 E 4

-60

L A T A N D

-70 -80

2 O'

J 20

0

380,__ T 0 M 300 B

t 40 ELAPSED

J 60 FLIGHT TIME

SEP

J 80 (5

19

J J 100 120 MINUTE INTERVALS)

L 0 N G

-90 40

DC8

-

° -°

0 2801

% "..

Z 0 N 200 E

_-

°-

°-_

180 0

__°°

---------__---.__.-_________---.-"

l

I

l

20

40 ELAPSED

FLIGHT60

I TIME

_

l

l

120 MINUTE 100 INTERVALS)

Figure 9i. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight

I 140

19 as mapped onto and altitude along path (bottom).

a polar with the

237

SEP

14_

21

DC8

A L lZ T I0 I T 8 U D 6 E

4

K M

2

_

180

_

I00

_

50

_ 0 -80 _ -I00

0 0

[ • 0

I 40 ELAPSED

i 60 FLIGHT

I 80 TIME

SEP

360 _

(6

21

I I00 MINUTE

I [ 120 140 INTERVALS)

160

I I 120 140 INTERVALS)

I 160

L A T A N D L 0 N G

-180

DC8

"L

0 M 300

0 280 Z 0

N _00_ E 1801 0

I S0

-"--. -I.... 40 ELAPSED

_ I 60 FLIGHT

=_

I 80 TIME

I'-

I I00 (8 MINUTE

Figure 9j. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight 238

21 as mapped onto a polar and altitude along with the path (bottom).

SEP

14 A L 12

24

DC8

_ -80

..LAT

"

-60

T 10 I

-70

T U D E

8

-80

4

-100

K M

2

_ -110

-90

6

0 0

I 20

I 40 ELAPSED

I 60 FLIGHT

.-_-

I 80 (8

TIME

SEP

350 T 0 M 300 S

24

I 100 MINUTE

L 0 N G

-120

I 120 INTERVALS)

140

DC8

_

---._

0 2B0 Z 0 N 200 E

-_%

"_--.

_-_% ----_.

180

L A T

o

I

20

I

4o ELAPSED

_

--- L_:_;

eo

FLIGHT

.-"

TIME

_---o.-"

--i

---

80 (8

MINUTE

I

loo

I

12Q

I

14o

INTERVALS}

Figure 9k. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight

24 as mapped onto a polar and altitude along with the path (bottom). 239

SEP

14 A L

I0

T U D

8

E

DC8

_

A T

_

-60

"ALT A N

-70

D 6

-80 L 0

4 _

K M

L

-50

-...LAT

12

T I

26

-90

N G

2 0

I 40

20

ELAPSED

I 60 FLIGHT

I 80 TIME

SEP

I I00

(5

26

MINUTE

I 120

-lOG 140

INTERVALS)

DC8

380 T 0 M S

300

O

280'

_----__ _

----___

Z 0 N

__-_°

200

-°_

E

-

_°°----

---____

_- --._

160 0

I 20

I 40 ELAPSED

FLIGHT

--

i

I 60 TIME

_

i MINUTE

I00

Figure 91. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight 240

I 12Q INTERVALS)

I 140

26 as mapped onto and altitude along path (bottom).

a polar with the

IS_ A L 10 T I 8 T U 6 D E 4

SEP ALT

29

DC8

_00

/

L A T

100 A N D _A_, -100

K M

2 0

I _0

0

I 40 ELAPSED

I 60 FLIGHT TIME

SEP

380 T 0 M 300 S

i I -80 I00 ISO (8 MINUTE INTERVALS)

29

DC8 °---

-° -

. -° -. .

0 280 Z 0 N 200 E

-oo_

150 0

I 20

I 40 ELAPSED

/----

I 60 FLIGHT

..... TIME

I 60 (8

I I 100 120 MINUTE INTERVALS)

Figure 9m. Flight Path of the DC-8 mission for September projection (top) and as a time series of latitude, longitude, corresponding TOMS total-ozone estimates along the flight

j 140

29 as mapped onto a polar and altitude along with the path (bottom). 241

4.

REFERENCES

Ardanuy, P., J. Victorine, F. Sechrist, A. Feiner, L. Penn, and the RDS Airborne Antarctic Ozone Experiment Team, 1987: Final report of the near-real-time TOMS, telecommunications, and meteorological support for the 1987 airborne Antarctic ozone experiment, NASA Contractor Report, in press. Austin, J., E. E. Remsberg, R. L. Jones, and A. F. Tuck, 1986: Polar stratospheric clouds inferred from satellite data, Geophys. Res. Lett., 13, 1256-1259. Callis, L. B., and M. Natarajan, 1986: The Antarctic ozone minimum: Relationship to odd nitrogen, odd chlorine, the final warming and the ll-year solar cycle, J. Geophvs. Res., 91, 1077110796. Chandra, S., and R. D. McPeters, 1986: Some observations on the role of planetary waves in determining the spring time ozone distribution in the Antarctic, Geophys. Res. Lett,, 13, 12241227. Crutzen, P. J., and F. Arnold, 1986: Nitric acid cloud formation in the cold Antarctic stratosphere: A major cause for the springtime "ozone hole," Nature, 324, 651-655. Dave, J. V., and C. L. Mateer, 1967: A preliminary study on the possibility of estimating total atmospheric ozone from satellite measurements, J. Atmos. Sci., 24, 414. desJardins, M. L. and R. A. Petersen, 1985: GEMPAK: A meteorological system for research and education. Preprints, First AMS International Conference on Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology. Los Angeles, CA, 313-319. Farman, J. C., B. G. Gardiner, and J. D. Shanklin, 1985: Large losses of total ozone in Antarctica reveal seasonal C1Ox/NO interaction, Nature, 315, 207-210. Fleig, A. J., K. F. Klenk, P. K. Bhartia, and D. Gordon, 1982: User's guide for the Total-Ozone Mapping Spectrometer (TOMS) instrument first-year ozone-T data set, NASA Ref. Publ. 1096. Heath, D., A. J. Krueger, and H. Park, 1978: The Solar Backscatter Ultraviolet (SBUV) and Total Ozone Mapping Spectrometer (TOMS) experiment, in The Nimbus-7 User's Guide, edited by C. R. Madrid, pp. 175-211, NASA Goddard Space Flight Center, Greenbelt, Md. Klenk, K. F., P. K. Bhartia, A. J. Fleig, V. G. Kaveeshwar, R. D. McPeters, and P. M. Smith, 1982: Total ozone determination from the Backscattered Ultraviolet (BUV) experiment, J. Appl. Meteorol., 21, 1672-1684. Koch, S. E., M. desJardins, and P. J. Kocin, 1983: An interactive Barnes objective map analysis scheme for use with satellite and conventional data, J. Clim. Appl. Meteor., 22, 1487-1503. Krueger, A. J., M. R. Schoeberl, and R. S. Stolarski, 1987: TOMS observations of total ozone in the 1986 Antarctic spring, Geophvs. Res. Letters, Vol. 14, No. 5, 527-530. Mateer, C. L., D. F. Heath, and A. J. Krueger, 1971: Estimation of total ozone from satellite measurements of backscattered ultraviolet earth radiances, J. Atmos. Sci,, 28, 1307-1311. McCormick, M. P., and C. R. Trepte, 1986: SAM II measurements of Antarctic PSC's and aerosols, Ge0phvs. Res. Lett., 13, 1276-1279. Newman, P. A., and M. R. Schoeberl, 1986: October Antarctic temperature and total ozone trends from 1979-1985, Geovhvs. Rcs. Lett., 13, 1206-1209. Nimbus Observation Processing System, 1986:Nimbus-7 Solar Backscattered Ultraviolet and Total Ozone Mapping Spectrometer (SBUV/TOMS), GRIDTOMS Tape Specification #T634436, 1-17. Schoeberl, M. R., and A. J. Krueger, 1986: The morphology of Antarctic total ozone as seen by TOMS, Geophys. Res. Lett., 13, 1217-1220. Stolarski, R., A. Krueger, M. Schoeberl, R. McPeters, P. Newman, and J. Alpert, 1986:Nimbus-7 SBUV/TOMS measurements of the spring time Antarctic ozone hole, Nature, 322, 808-811. Toon, O. B., P. Hamill, R. P. Turco, and J. Pinto, 1986: Condensation of HNO 3 and HCI in the winter polar stratospheres, Geophys. Res. Lett., 13, 1284-1287.

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5.

ACKNOWLEDGEMENTS

The Nimbus-7 TOMS total ozone data were reliably and regularly supplied to the Airborne Antarctic Ozone Experiment operations office in Punta Arenas. The quality, timeliness, and dependability of the near-real-time and delayed TOMS data sets permitted the TOMS total ozone observations to play a crucial role in the planning and successful completion of the aircraft flights. Without question, the reliable provision of the orbital and hemispheric TOMS observations played a central role in the outstanding success of the mission. The authors were provided assistance by many individuals during the course of the experiment. Without this help, the TOMS total ozone data could not have been delivered in a punctual manner, and indeed, the experiment may not have been possible. While it is not possible to name every individual who played a role, certain acknowledgements must be made. The authors would like to express their appreciation to John Sissala, Mike Doline, and other members of the GE/RCA Service group for scheduling the data transfer from the Nimbus-7 satellitc passes so as to obtain the telemetry in the quickest possible manner and for providing predictions of the Nimbus-7 orbital overpasses well in advance of the experiment. We also wish to thank Fred Shaffer, Hal Domchick, Herb Durbeck, and Scott Brittain of NASA/GSFC and the RMS Associates operations group for the smooth and continuous operations of the NSESCC during the experiment, and for adjusting the system maintenance schedule and job priorities to ensure the most rapid throughput of the TOMS data production on the IBM 3081. Also to be recognized are Robert Gray, Jerry Morrison, Damodar Goel, and Kirk Jones of STX who processed the raw TOMS data on the GSFC IBM 3081. The authors wish to thank the RDS telecommunications team, composed of James Victorine, Segun Park, Nasser Alizadeh, Susan Krupa, and Steven Gaines, who manned the communications center in Punta Arenas 24 hours a day, 7 days a week, and received the TOMS total ozone data. Recognition is due to Al Feiner and Woody Wheat of RDS who designed the real-time telecommunications network and monitored its installation and testing. We are also appreciative of Mary DesJardins of NASA/GSFC and Brian Doty and Ira Graffman of RDS for their timely modification of the GEMPAK software to permit its use in a southern hemisphere polar projection. We are also grateful to Brenda Vallette of RDS for the technical editing and assembly of this manuscript. Finally, we also wish to thank Arnie Oakes of NASA/GSFC, in his capacity as technical officer on the Nimbus Project, for helping to put together this uniquely qualified group of individuals that made the mission work.

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Natal Soace

Aerc_aut_s Ad_r_stralon

1. Report

No.

I_8A 4. Title

Report

and

Documentation

2. Government

Accession

Page

No.

3. Recipient's

Catalog

No.

RP-1201 and Subtitle

The 1987 Nimbus-7

5. Report

Airborne Antarctic TOMS Data Atlas

Ozone

Experiment

Date

- The March

1988

6. Performing

Organization

Code

Organization

Report

616 7. Author(s)

8. Performing

Arlin Frank Scott

J. Krueger, Philip E. Ardanuy, S. Sechrist, Lanning M. Penn, David D. Doiron, and Reginald N. Galimore

9. Performing

Organization

Name

Goddard Space Greenbelt, MD

E.

88B0107

Larko,

10. Work

Unit

No.

and Address

Flight 20771

11. Contract

Center

or Grant

13. Type of Report 12. Sponsoring

Agency

Name

Philip

E.

No.

and

Period

Covered

and Addre_

National Aeronautics and Space Washington, DC 20546-OOO1

15. Supplementary

No.

Administration

Reference 14. Sponsoring

Publicat Agency

ion

Code

Notes

Ardanuy,

Frank

S.

affiliated with Research and Scott D. Doiron and Reginald Research Corporation, Lanham, Flight Center. 16. Abstract Total played a central The near-real-time

Sechrist,

Lanning

Data Systems N. Galimore MD, 20706;

M.

Penn,

and

David

Corporation, L_, are affiliated with Arlin J. Krueger is

E.

Larko

MD, 20706; Science Applications with Goddard Space

ozone data taken by the Nimbus-7 Total Ozone Mapping Spectrometer role in the successful outcome of the 1987 Airborne Antarctic Ozone TOMS total ozone observations were supplied within hours of real

operations center for this purpose.

in Punta Arenas, The TOMS data

hole's dissolution to rotate. By the

is observed here end of November,

are

(TOMS) Experiment. time to the

Chile, over a telecommunications network designed specifically preparation and method of transfer over the telecommunication links are reviewed. This atlas includes a complete set of the near-real-time TOMS orbital overpas,, data over regions around the Palmer Peninsula of Antarctica for the period of August 8 through September 29, 1987. Also pro',ided in this atlas are daily polar orthographic projections of TOMS total ozone measurements over the southern hemisphere from August through November 1987. In addition, a chronology of the salient points of the experiment, along with some latitudinal crosssections and time series at locations of interest of the TOMS total ozone observations are presented. The TOMS total ozone measurements are evaluated along the flight tracks of each of the ER-2 and DC-8 missions during the experiment. The ozone hole is shown here to develop in a monotonic progression throughout late August and September. We find that the minimum total ozone amount is obtained on October 5, when its all-time lowest value of 109 DU is recorded. The hole remains well defined, but fills gradually, from mid-October through mid-November. The

17. Key Words

(Suggested

to begin in mid-November, when the hole elongates and begins the south pole is no longer located within the ozone hole.

by Author(s))

18. Distribution

Antarctic ozone hole, TOMS, Nimbus-7, ozone hole, total ozone, airborne Antarcti, ozone hole experiment, Total Ozone Spectrometer, field experiment 19. Security

Classif.

(of this report)

Unclassified NASA

FORM

1626 OCT 86

20.

Security

Statement

Unclassified-Unlimited

Mapping Subject Classif.

Unclassified

(of this page)

21. No. 252

of pages

Category

47

22. Price AI2 NASA-Langley,

1988