Applications
of
China’s
Ocean Satellites in 2009
State Oceanic Administration
October 2010
Table of contents
1．INTRODUCTION ........................................................................................................................... 2
2．ADVANCES IN OCEAN SATELLITE PROGRAM ................................................................... 3
2.1 ADVANCES IN HY-1C/1D SATELLITE R & D ................................................................................. 4
2.2 R & D OF THE HY-2 SATELLITE MISSION........................................................................................ 5
2.3 CONSTRUCTION OF THE OCEAN SATELLITE GROUND APPLICATION SYSTEM ................................... 7
3. OPERATION OF OCEAN SATELLITE AND THE GROUND APPLICATION SYSTEM ..... 9
3.1 IN-ORBIT OPERATION OF OCEAN SATELLITE .................................................................................... 9
3.2 OPERATION OF GROUND APPLICATION SYSTEM ............................................................................... 9
3.3 SATELLITE CALIBRATION AND VALIDATION ................................................................................... 13
4．SATELLITE OCEAN APPLICATIONS ..................................................................................... 15
4.1 OCEAN DISASTER MONITORING AND FORECASTING ...................................................................... 15
4.2 MARINE ENVIRONMENTAL MONITORING AND PROTECTION .......................................................... 23
4.3 INTERNATIONAL AND REGIONAL COOPERATION ............................................................................ 32
1
1．Introduction
Considerable progress was achieved in China’s ocean satellite
missions in year 2009. The ground application system for ocean satellites
operates well, and applications of ocean satellites have been further
extended.
The Ocean-1B (HY-1B) satellite operates stably in orbit. 2,018
orbits of measurements from HY-1B were received in 2009 and the
accumulated raw data reached 8,472 GB. 2,778 orbits of data from
EOS/MODIS satellite were also received with accumulated raw data of
6,620 GB. The ocean satellite data has been distributed and extensively
applied further into a variety of fields. National Satellite Ocean
Application Service (NSOAS) provides near real-time (NRT) data to the
government agencies for oceanographic environmental monitoring and
forecasting, processes and develops all levels of ocean satellite data
products and distributes them to domestic oceanographic departments,
research institutes, universities and space-related industries. Meanwhile,
NSOAS also actively promotes the applications of ocean satellite data in
cities and provinces in the Bohai Sea Rim Area and the South China Sea,
making the ocean satellite data an important player in such areas as ocean
resources exploration and management, ocean environment monitoring
and protection, ocean disaster monitoring and forecasting, ocean research
2
and international and regional cooperations.
The upgrade and modification of HY-1B ocean satellite ground
application system have been completed with good results. The
construction work of Mudanjiang ground station, located in the northeast
China, has been progressed well, capable of receiving data from HY-1B
satellite.
The preliminary scientific and technical requirement documents
have been prepared and evaluated successfully. The engineering work for
HY-2 satellite has been carried out smoothly, with significant progress .
2．Advances in ocean satellite program
Ocean satellite program is valued as a key step toward
understanding and utilizing the oceans in the top levels of China
administration. Mr. Sun Zhihui, administrator of State Oceanic
Administration (SOA), together with other members of Chinese People's
Political Consultative Committee (CPPCC), submitted a proposal “setting
up ocean satellite missions from experimental stage to operational stage”
to the 11th CPPCC conference. Dr. Ni Yuefeng, top official of National
People’s Congress (NPC) overseeing environment and resources
protection, submitted a proposal “on the establishment of China’s ocean
satellite specific program” to the 10th NPC conference.
3
The ocean satellite project proposal has been submitted in 2009. In
order to strengthen the construction of space infrastructure, the State
Oceanic Administration (SOA) submitted the project proposals for the
follow-on operational ocean satellites during the 12th Five-Year period,
including HY-1C/1D and HY-1E/1F constellations and HY-2B satellite.
The steering committee members from NPC, CPPCC, Chinese Academy
of Sciences (CAS), China Aerospace Technology Incorporation, General
Armament Department, General Staff Headquarters and Navy approved
the proposal. In December 2009, the project proposal was submitted to
the central government for further approval from the State Council.
In 2009, HY-2 satellite mission passed its prototype development
stage and entered into the flight mode development; the proposal of
ground application system was reviewed and submitted for approval. The
equipment of precise orbit determination system, DORIS, was introduced
and HY-2 satellite airborne flight calibration experiment was also carried
out.
2.1 Advances in HY-1C/1D satellite R & D
China has basically realized the transformation of ocean water color
remote sensing applications from experimental to operational stage using
HY-1A and HY-1B satellites. In 2009, NSOAS and Aerospace
Dongfanghong Satellite Company Ltd (DFH Satellite Co., Ltd)
4
conducted
an in-depth
analysis on
main
techniques such
as
double-satellite network with a morning and an afternoon satellite,
satellite orbit and period of satellite coverage. According to the demand
of end users, it has been tentatively determined the HY-1C/1D satellite
network is composed of a morning and an afternoon satellite with main
technical index being upgraded on the basis of HY-1A/1B. The new
satellites are capable of taking broad images out of nadir, in order to
increase the number of observations and coverage areas, and to reduce
the influence of clouds and sun glints. Additionally, to meet the demand
for medium- and high-resolution data coverage for monitoring natural
disasters that include enteromorpha prolifera in the Yellow Sea and sea
ice in the Bohai Sea, oil spill pollution, red tides, and to consider the
continuity of program, technical problems and business growth, the
coverage width of Costal Zone Imager (CZI) will be increased and the
selected spectrum bands and resolution will be reset to suit the coastal
zone monitoring.
2.2 R & D of the HY-2 satellite mission
The prime contractor and subcontractors of the satellite system and
its payloads conducted a series of tests on the prototype of HY-2 satellite
and achieved good results. On December 23, 2009, HY-2 satellite began
its formal flight mode development after passing a panel review
5
organized by the prime contractor, China Academy of Space Technology
(CAST).
The NSOAS and the French company Thales Alenia Space signed a
contract for purchasing the DORIS system after several rounds of
technical and commercial negotiations. According to the contract,
NSOAS imported the electronics and ground test equipment for DORIS
system in 2009.
The Chinese Flight Test Establishment, the contractor of aircraft
experiment, conducted the airborne flight calibration experiment in
December 2009 in the vicinity of Hainan Province (Figures 1 and 2).
They have accomplished several flights after coordinating with several
other institutes. According to the schedule, the airborne flight calibration
experiment was completed in the early 2010.
In parallel with satellite mission and engineering project, NSOAS
organized, for the first time, the satellite-ground interface experiment
from 22 to 29 July 2009. The experiment results indicated good match
between the data link system of the HY-2 prototype, simulated satellite
signal source, and the Beijing ground station in terms of communication
channel and data format. Results of the interface experiment are
successfully consistent with the experiment outlines and specifications.
6
Figure 1. HY-2 aircraft experiment.
Figure 2. Synchronous oceanographic and atmospheric experiments at sea during
HY-2 satellite airborne flight calibration test.
2.3 Construction of the ocean satellite ground application system
The construction work of the Mudanjiang ground station, part of
7
the ocean satellite application system, progressed remarkably in 2009,
capable of receiving the overpass ocean satellite data. SOA approved the
Mudanjiang ground station general proposal in the early 2009, which is
also supported by the local Mudanjiang Municipal Planning Agency.
After the public bidding procedure of construction project and associated
project, the opening ceremony for the first construction project was held
in the Mudanjiang City on 18 June 2009.
The phase 1 project of the office building began on 10 July 2009,
indicating the Mudanjiang ground station entered into its construction
stage. The framework of the office building was completed on 10
September and the decoration was completed on 12 December 2009.
On 24 October 2009, the receiving antenna foundation passed the
vibration resonance frequency test in the Mudanjiang ground station. The
construction of station went smoothly, and successfully received the
HY-1B satellite data on 24 December 2009.
Figure 3. Mudanjiang ground station opening ceremony.
8
3. Operation of ocean satellite and the ground application
system
3.1 In-orbit operation of ocean satellite
HY-1B satellite has been in a good condition, and both of its
onboard sensors, Chinese Ocean Color and Temperature Scanner
(COCTS) and CZI, are operating stably. Until December 31, 2009,
HY-1B had been operating in orbit for 365 days and successfully
delivered 2,018 orbits of data, including 711 orbits for China seas and
lands, 947 orbits for areas outside China and 360 orbits of night-time data
replay. The HY-1B satellite can cover the whole globe (Table 1).
Region
Counts
Region
Asia
55 Pacific
Europe
28 Indian Ocean
Africa
61 Atlantic
N. America
32 Arctic
S. America
10 Antarctic
Australia
153 Mediterranean
Table 1. Orbit counts outside China
3.2 Operation of ground application system
（1）Data receiving, processing and archiving
9
Counts
256
29
161
6
29
127
The preprocessing, processing and archiving of the HY-1B data
provide support for the routine operation of ground application system.
The accumulated HY-1B satellite data processed and archived in 2009
reached 8.5 TB.
Besides the routine operation for HY-1B satellite, the ground
application system also receives and preprocesses data from the United
States EOS satellites (Aqua and Terra).
The receiving stations of the satellite ground application system,
located in Beijing, Sanya and Hangzhou, operated smoothly in 2009. All
the receiving equipment worked normally and completed the receiving
mission with good results. The transformation of ground station computer
room in Hangzhou station has been completed and the receiving antenna
for geostationary MTSAT has been upgraded from 2.3 m to 3.2 m in
diameter.
（2）Data distribution
NSOAS distributes ocean satellite data products to domestic satellite
users through ways including website, data medium and directed
transmission. 408 GB of HY-1B satellite products were distributed to 26
domestic users in 2009, including ocean management agencies, research
institutions, universities and space agencies (Table 2). To meet the
demand for ocean satellite data from 3 provinces and 1 city in the Bohai
Sea Rim Area and relevant provinces and cities around the South China
10
Sea, NSOAS distributes ocean satellite data to Liaoning, Shandong,
Hebei, Tianjin, Guangdong, Hainan and Jiangsu provinces and municipal
cities through specific channel everyday. The distributed data mainly
includes the HY-1B satellite data and the MODIS data, providing satellite
data support to users in coastal provinces and cities. The NSOAS website
registered 23,582 unique visits in 2009 with 40 GB data downloaded in
total.
Users
percentage
volume（MB）
governments
operational
agencies
15%
61,200
46%
186,080
Research institutes
27%
111,760
aerospace agencies
12%
48,960
Total
Table 2. Ocean satellite data distribution
408,000
200000
180000
160000
140000
120000
100000
80000
60000
40000
20000
0
186080
111760
61200
管理部门
48960
业务部门
科研院所
航天部门
Figure 4. Histogram of HY-1B data products distribution.
11
12%
15%
27%
46%
管理部门
业务部门
科研院所
航天部门
Figure 5. Pie chart of HY-1B satellite data distribution.
Users
Product level
L1B
Usage
Marine environmental
monitoring and
forecasting
Marine environmental
monitoring and
forecasting
SST and sea ice
prediction
Marine environmental
monitoring and
forecasting
Ocean remote sensing
retrievals
North Sea Branch, SOA
L1B、L2
South Sea Branch, SOA
National Marine Environmental
forecasting center
L1B、L2
L1B
Oceanic research
L1B
Oceanic research
L1B
Oceanic research
L1B、L2
Marine environmental
L1B、L3D
National Marine Environmental
Monitoring Center
National Marine Data & Information
Service
The First Institute of Oceanography,
SOA
The Second Institute of Oceanography,
SOA
The Third Institute of Oceanography,
SOA
L1B、L2
Shandong Marine Environmental
12
Monitoring Center
Hainan Marine Environmental
Monitoring and Forecasting Center
L1B、L2
DFH Satellite Co., Ltd
L1B
Shanghai Tech. Phys. Inst., CAS
L1B
Remote Sensing Institute, CAS
L1B
monitoring and
forecasting
SST and sea ice
prediction
Marine environmental
monitoring and
forecasting
Marine environmental
monitoring
Marine environmental
monitoring
Marine environmental
monitoring and
forecasting
Ocean satellite
development
Ocean satellite payload
development
Ecology evaluation for
the Three Gorges project
East Sea Fishery Inst., CAS
L1B
Ocean Fishery
China Ocean University
L1B、L2
Ocean color and ecology
Hebei Marine Prediction Center
L1B、L2
Tianjin Marine Environmental
Monitoring Station
Liaoning Marine Environmental
Monitoring Station
Fujian Marine Environmental
Monitoring Center
L1B、L2
L1B、L2
L1B、L2
Shanghai Ocean University
L1B
Marine sciences
Table 3. Examples of HY-1B data distribution in 2009.
Meanwhile, NSOAS distributes MODIS data products to China
Meteorological Administration (CMA) everyday as a routine operation
with accumulated transmitted data of 2,667 GB in 2009, supporting the
stable operation of national MODIS data sharing service platform.
3.3 Satellite calibration and validation
Aiming at the HY-1B satellite radiation calibration and validation,
NSOAS conducted radiometric calibration test in the north of South
China Sea, and the two sensors onboard HY-1B were calibrated with 6
13
calibration methods using the test results. The calibration methods used
include
simultaneous
vicarious
calibration,
system
calibration,
cross-calibration with MODIS and cross-calibration with MERIS. These
experiments and calibrations guaranteed the accuracy and reliability of
HY-1B satellite data and further improved the quality of HY-1B satellite
data, laying a basis to promote its applications.
The in-situ simultaneous experiment of HY-1B satellite sensor was
carried out in the South China Sea from February 16 to March 2, 2009
with effective 11 working days. Observations from 46 sites were made in
this experiment and 437 MB of in-situ data were obtained, including
water body optical properties (apparent and inherent), infrared radiation
properties, atmospheric optical properties, particular content of water and
its optical absorption properties (Figure 6).
NSOAS makes long-time continuous tracking of the calibration
coefficients of COCTS remote sensor during its operation using
cross-calibration method with MERIS and COCTS. MERIS passes over
China basically at the same time with COCTS. Its data is stable with high
accuracy, so the calibration coefficient obtained from selected MERIS
and COCTS data are reliable and meet the calibration requirement.
14
0.018
0.016
0.014
ch1
ch2
ch3
ch4
ch5
ch6
ch7
ch8
定标系数
0.012
0.01
0.008
0.006
0.004
0.002
0
100
200
300
400
500
发射后天数
600
700
800
Figure 6. Time series of calibration coefficients from the in-situ simultaneous
experiment in the South China Sea.
4．Satellite ocean applications
NSOAS actively promoted ocean satellite data to coastal provinces
and cities in 2009 and conducted routine operation in the field of sea
surface temperature monitoring, sea ice monitoring, red and green tide
monitoring using other satellite data, resulting in wide applications of
ocean satellite data in ocean disaster monitoring and forecasting, ocean
environment monitoring and protection, and international and regional
cooperation.
4.1 Ocean disaster monitoring and forecasting
（1）Marin oil spill monitoring
NSOAS monitored in real-time some important marginal seas
15
including the Bohai Sea, the East China Sea and the South China Sea for
a year using data from ENVISAT of ESA, Canadian Radarsat-1 and 2,
Italian COSMO-Skymed-1, 2 and 3, and China’s remote sensing satellites
together with marine oil spill transport path forecast system and oil spill
thematic fundamental geographic information database. Based on those
monitoring data, the oil spill monitoring thematic reports and thematic
images were developed and supplied to users including China Sea
Monitoring Corps and North China Sea, East China Sea and South China
Sea corps.
To better monitor the oil spill in the China Seas, NSOAS greatly
increased the remote sensing monitoring frequency using satellites in
2009. The monitoring frequency in the Bohai Sea was increased to 2-3
days, 3-4 days in the East China Sea and the South China Sea, and 1-2
days can be guaranteed in emergency. At the same time, NSOAS and
China Sea Monitoring Corps established a joint response mechanism for
oil spill remote sensing monitoring in emergency. On March 31, 2009,
NSOAS monitored an oil spill belt of oil production platform in the north
of the Yellow River Estuary and initiated the joint mechanism for oil spill
monitoring and sent the information to China Sea Monitoring Corps.
China Sea Monitoring Corps sent ships to make in-situ monitoring and
found the oil spill belt at 17:00 of March 31, which was 20 nautical miles
southeast of the remote sensed location. The success of the mission for
16
the first time showed the joint mechanism for oil spill remote sensing
monitoring is effective.
In 2009, NSOAS totally processed 722 scenes of oil spill remote
sensing monitoring data, including 610 scenes from ENVISAT-ASAR, 22
scenes from Radarsat-2, 25 scenes from COSMOS, 28 scenes from
ALOS, 18 scenes from RG-1, 6 scenes of emergency programming data
and 13 scenes from HJ satellite data. 308 monitoring reports were issued
in 2009, including 171 for the Bohai Sea, 102 for the South China Sea
and 35 for the East China Sea. Totally 68 abnormal information were
released in 2009, among which 43 for the Bohai Sea, 22 for the South
China Sea and 3 for the East China Sea.
17
Figure 7. Oil spill near the central region of the Bohai Sea on 31 March 2009.
（2）Red tide monitoring
NSOAS monitored green tide and red tide offshore China using
HY-1B and EOS/MODIS satellite data and reported the results to related
government agencies and enterprises in time. 94 reports on green tide
monitoring and 2 on red tide were distributed to relevant departments in
2009, which provided information service for red tide disaster monitoring
and prevention.
In 2009, given the position, domain and drift information of red and
green tides provided by NSOAS, the North China Sea Branch of SOA
conducted an airborne monitoring and responded the event with a proper
monitoring procedure. The marine hazard monitoring results are quickly
formed based on the surface characteristics of red and green tides with
visual aids and data retrievals.
18
Figure 8. Red tide retrievals on 3 June 2009.
Figure 9. Aircraft photo of the green tide on 12 June 2009.
19
Figure 10. Map of the green tide experiment region.
Figure 11. Green tide monitoring map based on remote sensing
techniques in the Yellow Sea region on 15 July 2009.
20
Figure 12. Red tide monitoring map in the South China Sea in 2009.
（3）Sea ice monitoring
In 2009, NSOAS monitored the sea ice in the Bohai Sea and in the
north of the Yellow Sea in real time and developed sea ice monitoring
real time products using HY-1B satellite data and combined with related
data (Figures 13 and 14). Those products were provided to users
including National Marine Environmental Forecasting Center (NMEFC),
North China Sea Branch of SOA, National Marine Environment
Monitoring Center and 3 provinces and 1 city in the Bohai Sea Rim Area.
In 2009, there were 431 real time sea ice images of HY-1B, 1,180 of
MODIS, 268 of NOAA and 4 of BJ-1 (Beijing-1 satellite) were
developed and provided to end users in total. Together with quantitative
information such as sea ice thickness, concentration and grid data
developed from MODIS inversion, these products have become reliable
basic data sources and quantitative numerical products for China’s sea ice
forecast (Figures 15 and 16). Remote sensing data has become essential
to operational sea ice prediction.
21
Figure 13. Sea ice coverage in the Bohai Sea and the north of Yellow Sea on 29
January 2009.
Figure 14. Retrieved sea ice distribution in the Bohai Sea and north of Yellow
Sea (January 29, 2009).
22
Figure 15. Sea ice 24h forecasting for 14 January 2009.
Figure 16. Sea ice coverage near Changxing Island on 18 January 2009.
4.2 Marine environmental monitoring and protection
（1）Water color environment monitoring
23
In 2009, in order to improve the retrieval accuracy of HY-1B
satellite data, NSOAS further updated the atmospheric correction
algorithm for HY-1B satellite on the basis of experimental data obtained
at seas and on lands, as well as other related data. NSOAS developed
water color retrieval algorithm and data substitution technology used in
offshore China and integrated related technologies in ocean satellite
ground application system.
NSOAS developed periodically the sea water color information such
as 8-day, monthly, and quarterly averaged chlorophyll concentration
distribution in areas under the jurisdiction of China and adjacent sea
areas, and sea water color environment information products of partial
area of ocean and provided to related industries and departments for their
uses in 2009.
24
Figure 17. Map of averaged chlorophyll concentration distribution in offshore
China and adjacent sea areas from January to March, 2009
Figure 18. Map of squid prediction in the north Pacific on 17 August 2009.
25
Figure 19. Map of Argentina squid distribution prediction in the southwest
Atlantic on 6 April 2009.
In 2009, aiming at national strategic plan “foster and strength
pelagic fishery”, Shanghai Ocean University (SOU), NSOAS and
NMEFC established open ocean fishery prediction lab. The fishery
prediction lab meets China’s open ocean fishery demands, and has
developed the north Pacific squid short-term prediction system based on
HY-1B satellite, HY-1B fishery environment prediction system, Peru
squid fishery prediction system, and Argentina squid prediction system.
Using the near real-time observations from HY-1B and other satellites in
combination with the fishery prediction system, the lab routinely makes
7-day squid analyses and predictions in the north Pacific, the southwest
Atlantic, and the southeast Pacific. The fishery prediction is operational,
with 28 issues published from May to November 2009 for the north
26
Pacific, 24 issues (January to April) for the southwest Atlantic, and 53
issues (January to April) for the southeast Pacific. The fishery prediction
and analysis play an important role in China’s open pelagic fishery,
making significant contribution to the national economy.
（2）Sea surface temperature (SST) monitoring
NSOAS produced 365 domestic daily sea surface temperatures
(SST), 36 domestic ten-day averaged SST and 12 domestic monthly
averaged SST data products using infrared remote sensing data obtained
by HY-1B satellite and EOS/MODIS satellite in 2009. At the same time,
NSOAS also developed SST data for fisheries in southeast and northwest
of the Pacific Ocean as well as southwest of the Atlantic Ocean. These
products were used by forecast and marine fishery departments to make
corresponding SST forecast and ocean fishery environment products and
eventually to serve the public and relevant marine industrial departments.
27
February
May
中国海及邻近海域 8 月平均海面温度
中国海及邻近海域 10 月平均海面温度
August
October
Figure 20. Monthly averaged sea surface temperature of China seas and the
adjacent ocean areas.
28
Figure 21. Remotely sensed sea surface temperature used for marine environmental
forecasting.
（3）Suspended sediments and coastline monitoring
In 2009, suspended sediments and coastline near the Yangtze River
delta were analyzed using the HY-1B ocean satellite. The distribution of
the suspended sediments and coastlines is shown in Figure 22.
29
Figure 22. Distribution of the suspended sediments and coastlines near the
Yangtze River delta.
Using the HY-1B data and other historical satellite products,
variations of the Yangtze River delta coastlines were analyzed to get the
varying coastlines over the past 20 years. Comparison between the 1989
Landsat TM imagery (left panel, Figure 23) and HY-1B CZI imagery
(right panel) indicates significant change of islands near the mouth of
Yangtze River. In 1989, the Xinglong sandbar and Yonglong sandbar are
completed separated from Chongming Island (the big island in Figure 23).
However, they adjoin together, shown in Figure 23, after 20 years of
30
erosion, deposition and reclamation activities.
Landsat, 1989
HY-1B, 2009
Figure 23. Images of the Yangtze River delta in 1989 (left) and 2009 (right)
The suspended sediments near the Yellow River delta were also
monitored continuously in 2009, shown in Figure 24.
Figure 24. Distribution of the suspended sediment density near the Yellow River delta
from HY-1B CZI.
31
4.3 International and regional cooperation
The international cooperation on ocean satellite was strengthened in
2009. NSOAS actively initiated international cooperations, promoted the
advance of international cooperation on ocean satellite missions and
fulfilled the introduction of the precision orbit determination equipment,
DORIS, for HY-2 satellite and the international satellite frequency
coordination of HY-2 satellite as well.
To strengthen the scientific and technical exchanges between
Australia and China, NSOAS signed a Memorandum of Understanding
(MOU) with University of New South Wales (UNSW) and the
Cooperative Research Centre for Spatial Information (CRCSI).
NSOAS held a China-France ocean satellite technology exchanges
meeting in October 2009. More than 60 experts and scholars from the
two countries attended the meeting and exchanged their results on the
related projects.
On 18 November 2009, 85 officials from ocean and fishery
departments of 33 coastal developing countries visited NSOAS.
32
Figure 25. China-France ocean satellite technology exchange meeting held in
Xi’an, 2009.
Figure 26. Officials from ocean and fishery departments of 33 coastal developing
countries visited NSOAS in 2009.
33