In a recent issue of this quarterly it was indicated that, in the
post-2000 era, two general classes of mission are being proposed
by the Agency:
This article also announced that, over the period 29 May to 31 May, scientists from the fourteen ESA Member States had been invited to gather in Granada to consider nine candidate Earth Explorer Missions. This is the first stage in a process of review that will ultimately lead to the selection of a sub-set of these missions for Phase-A study.
In assessing these nine missions, seven selection criteria have to be taken into account, namely: relevance to the ESA research objectives for Earth observation; need, usefulness and excellence; uniqueness and complementarity; degree of innovation and contribution to the advancement of European earth-observation capabilities; feasibility and level of maturity; timeliness; programmatics.
The specific objectives of the Granada meeting are two-fold: firstly to present the nine candidate missions to the European scientific community, giving it the opportunity to resolve queries, and secondly to provide the European scientific community with the opportunity to comment directly on the nine missions and related scientific priorities prior to the initiation of the peer review.
In preparation for this meeting, nine Mission Working Groups were set up to produce Reports for Assessment on each of the nine candidate Earth Explorer Missions. These were published (and circulated to those registering in time for the meeting) at the end of April. They are available from ESA Publications Division as part of the ESA SP-series of publications [i.e. SP-1196 (1- 9)]. The nine candidate Earth Explorer Missions are as follows (not in order of priority):
(a) A Gravity Field and Steady-State Ocean Circulation Mission -intended to advance work in the areas of steady-state ocean circulation, physics of the Earth's interior and levelling systems (based on GPS); to provide the data required to formulate global and regional models of the Earth's gravity field and the geoid (its reference equipotential surface) to high spatial resolution and accuracy.
(b) An Earth Radiation Mission - intended to advance understanding of radiative processes in maintaining the present climate and in governing the amplitude and evolution of large- scale climate anomalies; to provide global observations of cloud and aerosol fields (including both characteristics and distribution in the vertical) coupled with observations of radiative fields and temperature and water-vapour profiles.
(c) A Land-Surface Processes and Interactions Mission -intended to observe surface characteristics associated with land-surface processes and land/atmosphere interactions at local scales; to advance the understanding of these interactions on a global scale by extrapolating through space and time using process models; to enhance the capability to model and hence to advance the capability to manage our environment and its resources.
(d) An Atmospheric Dynamics Mission - intended to contribute to the correction of a major deficiency in the current (meteorological) operational observing network as well as the study of the Earth's global energy balance (i.e. global circulation and related features such as the El Nino and the Southern Oscillation); to provide global observations of three- dimensional wind fields.
(e) An Atmospheric Chemistry Mission - intended to advance understanding of the chemistry of the upper troposphere/lower stratosphere region, the exchange processes and its radiative balance; to provide global observations of ozone and related species (including nitrogen and chlorine oxides, precursors of tropospheric ozone etc.) together with water vapour and temperature.
(f) A Magnetometry Mission - intended to advance knowledge and understanding of the Earth's interior structure and motion as well as the ionosphere, the magnetosphere and solar wind coupling; to provide observations of the magnetic field near the Earth, including both the part that originates deep within the Earth's interior (main field and secular variations) and the external fields (due to electric currents in the ionosphere and the magnetosphere) plus the lithospheric magnetic anomaly field.
(g) A Precipitation Mission - intended to advance understanding and knowledge of precipitation for use in the development of precipitation schemes in climate and weather prediction models; to provide observations of rainfall estimates, notably in tropical and mid-latitudes regions.
(h) An Atmospheric Profiling Mission - intended to contribute to climate change research as well as to operational meteorology by advancing knowledge of the upper troposphere and lower stratosphere; to provide global observations of temperatures in the upper troposphere and lower stratosphere plus water-vapour profiles in the lower troposphere.
(i) A Topography Mission - intended to advance knowledge of the role of the cryospheric component of the ocean fresh water and salt budget, in particular for high-latitude ocean circulation, and its corresponding impact on sea level change; to measure seasonal and inter-annual fluctuations in a) the sea-ice roughness (and hence thickness), b) the mass budget of ice sheets and glaciers and c) the high-latitude ocean circulation.
The Peer Review will be initiated immediately following the meeting, culminating with a decision in the Autumn by the Earth- Observation Programme Board on which of the nine candidate Earth Explorer Missions should be selected for Phase-A study and the future of the remaining missions. Many of Europe's leading scientists will be involved in the review of the nine missions.
ESA EOQ 52