Access
This article is part of Nature's premium content.
Published online 5 December 2007 | Nature 450, 782-785 (2007) | doi:10.1038/450782a
News Feature
Earth Monitoring: Not enough eyes on the prize
The capacity of the United States to monitor Earth's vital signs is being stymied by tight budgets and poor coordination. Alexandra Witze reports.
It seems like such a little thing, the ability to lie back and look up at the full Moon. A moment of wonder or romance on a summer evening, perhaps, but not something vital to the way you do your job.
To read this story in full you will need to login or make a payment (see right).
Comments
Reader comments are usually moderated after posting. If you find something offensive or inappropriate, you can speed this process by clicking 'Report this comment' (or, if that doesn't work for you, email redesign@nature.com). For more controversial topics, we reserve the right to moderate before comments are published.
Two problems limit U.S. government funding for atmospheric and environmental observation by satellite. First, the government is spending many hundreds of billions of dollars on the wars in Iraq and Afghanistan, leading to much tighter funding of other programs (e.g., veterans' health care, and space programs in general). Second, the current administration does not want to know, or to let the people know, how badly the environment is being warmed and poisoned, so as to preclude citizens from protesting effectively. Protecting the environment is seen as "bad for business," which outweighs all other considerations. Gerald M. Levitis
The need for a series of global earth monitoring satellites is more pronounced at present than ever before. The recent IPCC reports of the projected impacts of climate change are quite alarming and are based, largely, on climate model simulations, as well as observations. In view of this it is absolutely imperative to acquire long term datasets of climate variables inorder to, both, understand the evolution of the biosphere-hydrosphere-atmosphere system vis-a-vis human induced climate change, and, to test, and confirm, the claims of the IPCC report. PS: In Table "Dimensions of the problem", it is shown that Leaf-Area-Index(LAI)is primarily measured from the field. However, NASA's MODIS instrument onboard both Terra and Aqua satellites provide 8-day and monthly measurements of LAI and FPAR (Fraction of Photosynthetically Absorbed Radiation). These datasets are being used in a wide range of applications and are available from both NASA and Boston University.
The article is an eye opener for everyone who needs to know the precise amount of information necessary for monitoring our Earth. Although, the number of satellites and independent variables (climate/ biophysical) available for monitoring are increasing day by day, it is imperative to put an ingot to the amount of information that, we as researchers and scientists, analyze and store. Multiple datasets of the same variables derived from different sensors definitely do serve the initial purpose of cross validation and is a helpful tool to establish the robustness of an algorithm in deriving higher level products. Although, time is a crucial factor and all efforts must collimate in validating similar products from different sensors within acceptable levels of uncertainty and precision. The higher level products are derived from raw data or first level products such as reflectance/ radiance/ backscatter based on numerous physical/ empirical algorithms and on the broader picture emerge out as the key variables quantifying changes in our planet (be it real time or in the decadal scale). Supporting the previous comment by Arindam, I absolutely believe that long term monitoring of biophysical/ climate variables from multiple sensors is a must to appreciate the changing face of our planet. Long term "consistent" datasets of LAI (Leaf Area Index) and FPAR (Fraction of Photosynthetically Absorbed Radiation) from multiple satellites like MODIS and AVHRR are on its way and will be a valuable asset in monitoring changing ecosystems and quantifying primary productivity over a historical time frame.
I remember when the vote to decide whether to build the International Space Station was before Congress. Most earth scientists strongly opposed it, seeing the ISS as a political and industrial boondoggle posing as science, and diverting huge sums away from building a significant number of earth observation satellites. They have been proven right of course, since the ISS is even less useful and more costly than had been feared. Recently, the diversion of far greater amounts of tax money to the war machine (and industrial profiteering) makes it much harder now and in the future to develop an admittedly expensive but useful earth observation infrastructure. Politics is far more important than sound science in shaping the future of scientific endeavor, and scientists, it seems, are not very good politicians.