Archive for the ‘IGOS Cryosphere’ Category

“Sea-ice” or “Sea ice”?

October 4, 2007

When writing the IGOS Cryosphere Theme Report, we were confronted with the painful decision on how to spell “sea ice”; i.e., “sea-ice” or “sea ice”. Strictly speaking, it should be spelled without hyphenation when it’s a noun, and hyphenated when it is an adjective. The problem is that it is usually an adjective, but it’s use as an adjective is so common (e.g., sea ice extent), that hyphens just get in the way. The purpose of hyphenation is to remove ambiguity, yet we always think of “sea ice” as a single entity and we are never confused as to which of the two words is modifying the noun that follows. For example, consider an “old-furniture salesman” versus an “old furniture salesman”. The former sells old furniture, while the later is (probably) and old salesman that sells furniture. But in “sea ice measurements” we are not confused because ice measurements that are in the sea are the same as measurements of sea ice.

Furthermore, when we refer to characteristics of sea ice (or sea-ice characteristics) such as sea ice motion or sea ice thickness, we’re always talking about a single entity, so that the three words really are a compound noun without ambiguity. One approach would be to not hyphenate these common compound nouns:

sea ice motion, sea ice concentration, sea ice thickness, etc.,

but to hyphenate the less common compounds:

sea-ice mapping, sea-ice scientists, sea-ice models, sea-ice analysis, sea-ice services, sea-ice studies, sea-ice observations

Another approach is to never hyphenate “sea ice”. A third approach is to always hyphenate it when used as an adjective. Note that whatever we do with sea ice, we should also do with lake ice and river ice. In the end, we went with the first approach, not hyphenating when used in a common compound noun and hyphenating it otherwise. It was not a unanimous decision!

It would be a lot easier if “sea ice” was a single word (“seaice”), but we didn’t want to go that far.



August 2, 2007

The IGOS Cryosphere Theme Report was approved at the 14th Session of the IGOS Partners held at the Intergovernmental Oceanographic Commission of UNESCO (United Nations Educational, Scientific, and Cultural Organization) in Paris on May 30. No fewer than 80 scientists in 17 countries contributed to the report, so this is truly a credit to the community. The comments by the Partners and theme leads where unanimously positive and glowing. They liked how comprehensive the report is, and referred to it as the “bible” of cryospheric observations. One of the two IGOS co-chairs concluded the comment period stating that “Ice is now a component of the Earth System”!

At the time of this writing, IGOS is preparing to merge with GEO (or be “absorbed” by GEO). GEO recognizes that the IGOS themes provide a wealth of information on observing system capabilities and requirements, information that is critical to GEO’s success. So both bodies have agreed that the IGOS themes will become part of GEO, though exactly how this will happen remains to be seen. One thing that will have to happen is that detailed recommendations or implementation actions from the various IGOS themes will need to be consolidated into broader tasks before they are incorporated into the GEO Work Plan.

So what’s next for the Cryosphere Theme? Implementation of the recommendations in our report is the priority. How? We’ll have to talk about that one.


April 16, 2007

The IGOS Cryosphere Theme report has been submitted for review and approval at the IGOS-P-14 meeting in Paris on 30 May 2007. After two years of workshops, discussions, and writing, the report is complete. Approximately 80 scientists from 17 countries contributed in one way or another.

The report is long, but it is a crosscutting theme and is unlike the other themes in terms of its scope. The many domains of the cryosphere – glaciers, ice sheets, sea ice, freshwater ice, snow, solid precipitation, and frozen ground – justify the level of detail without compromising the delivery of a complete set of recommendations for each domain.

The document is robust, with comprehensive background material, detailed observational requirements, analyses of shortcomings in the current observing systems, and, of course, a broad set of recommendations. I’m sure it’s not perfect, but it’s close.

Thanks to ALL who contributed.


They’ll listen if we tell them why it’s important

December 5, 2006

Our strategy of making recommendations based on the gaps between observational capabilities and requirements seems convincing and bulletproof. After all, if we need a certain level of measurement accuracy for an application, then how could any funding agency turn down a reasonable proposal to close the gap?

Well, that’s not enough. We need to be clear about the impact of more and/or better measurements. Will weather or climate predictions be improved? By how much? Will lives or infrastructure be saved? Will agricultural practices benefit? This is an obvious extension of what I said in an earlier blog entry (“Requirements”), that if an observation doesn’t have a requirement, then we shouldn’t be making it. Similarly, if improving an observation doesn’t have an impact, we shouldn’t be pursuing it. We need to tell the funding agencies what that impact is.

Of course, there’s always the possibility that we don’t yet know why we need a better measurement, but we’re pretty sure that we do. Unfortunately, “If you build it, they will come” is a harder approach to sell.



December 5, 2006

There have been many reports that give recommendations on how to improve the various observing systems. In most cases, the recommendations are based on how well we want to be able to observe a particular geophysical parameter rather than how well we need to be able to measure it. We know that we can do a better job of making an in situ measurement or estimating a value with remotely sensed data. We always want more measurements in space and time. But do we really need better and more measurements? Probably, but knowing that we can do better doesn’t necessarily justify the financial support. Why do we need a better measurement? How is the need defined?

For the Cryosphere Theme, we have taken the approach of defining observational requirements, examining the difference between our current capabilities and the requirements, and making recommendations based on the gaps. The term “requirements” is used often nowadays, but not always correctly. A measurement requirement depends on the application. Numerical weather prediction may need ice thickness at a different level of accuracy than the shipping industry. Avalanche forecasters need snow properties on a scale much different from climate models.

One definition a requirement is a threshold value of accuracy below which the observation will have no significant impact on the output of the application. One can imagine that an even higher level of accuracy might yield an even greater impact in the application. We call this the objective value. Unfortunately, it is not always easy to determine these values, but we must try. After all, if an observation doesn’t have a requirement, then one could argue that we shouldn’t be making it.


Our place in the universe of observing system initiatives

November 11, 2006

With so many international groups and activities whose goal is to improve the climate observing systems, it is not unreasonable to ask what we can do by creating yet another observing system enhancement initiative. There’s GEOSS (Global Earth Observation System of Systems), GCOS (Global Climate Observing System), GOOS (Global Ocean Observing System), GTOS (Global Terrestrial Observing System), GTN-P (Global Terrestrial Network for Permafrost), and more. Then there’s IGOS, the Integrated Global Observing Strategy, and its themes. With GEO/GEOSS being the “system of systems”, the current thinking is that the IGOS themes will feed into GEOSS; i.e., GEOSS should build on the Themes.

Why do we need a cryosphere theme? It’s really very simple: different components of the cryosphere are covered by the various G*OS’s, but none of them can treat the cryosphere as a whole, and therefore do not address the synergy between observations and modeling relevant to cryospheric observations and processes. That’s what we need to do, and it is a formidable task.