Newsgroups: lter.ced Path: LTERnet!news From: "Bruce P. Hayden" Subject: CED Vo. 1.2 Message-ID: <1992Mar20.133521.9169@lternet.washington.edu> Sender: news@lternet.washington.edu Organization: Long Term Ecological Research Date: Fri, 20 Mar 1992 13:28:41 GMT ***************************************************************** ***************************************************************** *** *** *** *********** *********** ********** *** *** * * * * *** *** * * * * *** *** * * * * *** *** * ********* * * *** *** * * * * *** *** * * * * *** *** * * * * *** *** * * * * *** *** *********** *********** ********** *** *** *** ***************************************************************** ***************************************************************** Vol.1 No.2 :::::: file name:CED1.2 :::::: April 1, 1992 ***************************************************************** ***************************************************************** CED is the Climate/Ecosystem Dynamics bulletin board of the LTER network. In CED you will find exchanges of ideas, information, data, bibliographies, literature discussions and a place to get to experts within the LTER community. We are interested in both climate controls on ecosystems and ecosystem controls on climate. As this is an inter-disciplinary activity, we hope to provide things that you might not come across in your work at your LTER site. CED is a product of the LTER climate committee and contributions to CED for general e-mail release may be sent to either David Greenland of Andrews LTER [Greenlan@oregon.uoregon.edu] or to Bruce Hayden of the Virginia Coast Reserve LTER [bph@envsci.evsc.virginia.edu]. We expect that the scope of CED will evolve and reflect the interests of the contributors and users of this service. CED will be issued as the preparation work gets done (monthly?). Back-releases of CED may be requested from Hayden by the file name given in the masthead. Feedback on CED from LTER scientists is welcome (non-$$$$ contributions also welcome.) For example, please forward citations of climate & ecosystem publications on your site. We will keep a LTER wide bibliography on Climate/Ecosystem Dynamics that we pass on via E-mail. ***************************************************************** ***************************************************************** *** *** *** *** *** FISH FALL FROM SKY AT NTL LTER *** *** *** *** Magnuson tells fish stories. *** ***************************************************************** ***************************************************************** Trout Lake Fish-from-the-Sky-Watch: NTL scientists in the know attribute the dispersal of fish in the glacial lakes strewn across the north woods landscape to airborne assaults from tornado lifted fishes and careless bait fishermen. Reports of animals of all sorts falling from the sky was a growth industry in the 1800s and the first quarter of this century. Since 1950, scientific professionalism has soared and journal articles on fish from the sky has plummeted! Fish that fall from the sky average 2-4 inches in length but there are fish as large as 1 foot that didn't get away. Fish falls typically leave a piscatory fingerling-print on the landscape that is long and narrow (100s of feet to miles in length). Both live and dead fish falls are on record. For example, Dateline 1886 Aberdeen, S.D.: Small fish found on the roofs of office buildings after a hard rain. And, in 1921 Gulf of Mexico water spout drops 30-50 menhaden 2-3 inches long on boat. Gudger, E.W. 1929. More Rains of Fishes. Annals and Magazine of Natural History 10:3:1 Other citations for NTL sky-watching, seine-wearers include: Baker, T. R. 1893. A Rain of Fishes. Science. 21:21:335. Fairhall, J. 1917. Things That Fall from the Sky. Sci. Am. 117:271. Jochelson, W. 1923. Fishes Fallen from the Sky. Science 58:516. Evans, Bergen 1946. Concerning Rains of Fishes. Science 103:713. Bajkov, A. D. 1949. Do Fish Fall from the Sky? Science 109:402. ***************************************************************** ***************************************************************** *** *** *** *** *** Small Mammals Make Dust Devils *** *** *** *** *** ***************************************************************** ***************************************************************** Dust devils are thought to be initiated by some chance event, perhaps an obstruction to a breeze, a pile of crushed rock, an automobile, the edge of a woods. R. L Ives studied dust devils in the Great Basin by following backwards the trail they etched on the desert surface. Geiger in his famous Climate Near the Ground quotes Ives as saying: "In most cases the track of a small animal in the desert, perhaps a rabbit or wolf, can be recognized from the trail of small whirls of dust it leaves behind. Observations we have made in this territory suggest the possibility that most dust devils are started by small animals." Ives recalls seeing a coyote trot across the desert kicking up a succession of small dust devils. Ives is known to have chased dust devils in his jeep with instruments on a stick that he could push into the dust devil. Jeep accidents aside, he estimated winds inside of up to 10 to 15 m/s. Ives watched kangaroo rats (Dipydomys sp.) being sucked up into a dust devil and fall out unharmed. To find the upward velocity in the dust devil he found the terminal velocity of a kangaroo rat by dropping it, "unhurt but angry", from a tower. The answer was it exceeded 25 miles per hour. Jackrabbits have also bee seen to be carried aloft. Tower studies indicate upward velocities in excess of 35 miles per hour. Jackrabbit was "stunned and internally injured on landing." Magnuson of Trout Lake thinks that fish get spread from lake to lake in the north woods lake district by tornados which are not uncommon there. He said nothing about the dispersal of the famous Trout Lake rats however. In Germany, people have been seen inside dust devils. The have a hard time with their "balance." Ives' Jeep once entered a dust devil and was airborne for a few yards! Dust devils are most common between 10 am and 4 pm and when the temperature gradient above the surface exceeds 10 degrees per 100 meters. It is in this superheated surface air the devils begin and in which a coyote or jackrabbit may cause the eddy to start and grow. (R.L. Ives (1947) Behavior of Dust Devils. Bull. Am. Met. Soc. 28:168-174.) ***************************************************************** ***************************************************************** *** *** *** *** *** LTER El Nino Study Group *** *** *** *** *** ***************************************************************** ***************************************************************** Sevilleta, Jornada, North Inlet, VCR, North Temperate Lakes expressed interest at the Trout Lake Soiree in a study group on El Nino and Ecosystem responses at LTER Sites. Downstream results might be 1) A workshop, 2) an intersite proposal, 3) Perhaps a Joint BioScience paper or something of that ilk. So, this is a first call to the LTER community. Have you detected an El Nino signal at your site. Are you interested in joining in the hunt and getting the benefit of experience on hand at other sites. As a start up we will use CED to keep things going and keep people informed. Send declaration of interest to Bruce Hayden [bph@envsci.evsc.virginia.edu]. ***************************************************************** ***************************************************************** *** *** *** *** *** GLOBAL CLIMATE CHANGE UPDATE *** *** *** *** *** ***************************************************************** ***************************************************************** Australia joins North America, Europe and Asia with rising minimum temperatures, not much change in daily maximum temperatures, narrowing daily temperature ranges, longer frost free seasons and increasing cloudiness. Could this be the long awaited global warming signature? Is this also a doom and gloom scenario for ecosystems? Inquiring minds will want to read P.A. Jones, (1991). Historical Records of Cloud Cover and Climate for Australia. Australian Meteorological Magazine 39:181-189. 1990 DEMOTED! LTERer's with long lasting neuron firing pathways will recall that 1990 was ranked as the second warmest year on record. Well, all the data are in now, not just the toasty warm cities, and it has been demoted to the 7th warmest. 1991 will also rank on the warm side but when all the non-city data is added to the heap we call average temperature, 1991 will probably come out around 13th in rank. Remember newspapers rarely print retractions. I have never seen a weather story retraction a year after the fact. If you want to see what a warm winter is like 1931-1932 was the warmest around Virginia 5 F higher than average for the three month period December, January and February. We, at least people of my parents generation, had peach blossoms at the end of January. No peaches that year. The winter was mild but the frost season end was not unusual. Cold air from Canada in April has little memory of earlier months. ***************************************************************** ***************************************************************** *** *** *** *** *** CLIMATE COMMITTEE DOINGS *** *** *** *** *** ***************************************************************** ***************************************************************** David Greenland (Andrews), Tim Kittell (CPER) and Bruce Hayden (VCR) have submitted a proposal to NSF Ecosystems to update and expand the climate monograph for LTER sites. Four new sections are planned: site descriptions for new LTER sites; climate variability analysis; projected climate changes at LTER sites and comparative climatology across sites. On funding we will turn on the afterburners and increase contact with the sites on the project. ***************************************************************** ***************************************************************** *** *** *** *** *** GRAPHS IN CED ISSUES *** *** *** *** *** ***************************************************************** ***************************************************************** With this issue we begin an experiment in sending graphics in our CED e-mail releases. As a trial run we offer the following on dewpoint temperatures, minimum temperatures and relative humidity. Y AXUS = MINIMUM TEMPERATURE (C) CED Graph |................................................................. |.....................................................#........... |................................................................. 20 |.................................................#............... |................................................................. |...........................................#..................... |................................................................. 10 |.......................................#......................... |................................................................. |..................................#.............................. |................................................................. 0 |.............................#................................... |................................................................. |........................#........................................ |................................................................. -10 |...................#............................................. |................................................................. |..............#.................................................. |................................................................. -20 |.........#....................................................... +----|----|----|----|----|----|----|----|----|----|----|----|----| -20 -10 0 10 20 30 DEW POINT TEMPERATURE (C) FIG. 1. The relationship between dew point temperature of the air and the minimum temperature of the day (usually at around 4:00 A.M.) The relationship is nearly linear Y = -.68 + X with an R^2 of .97 based on N =443. This relationship will hold for places with monthly average daily relative humidities of 65% or higher. So if you don't have good dewpoint data at your site use the your maximum minimum thermometer and find the daily minimum temperature! Steve Running uses this approach in his models to estimate a vapor pressure deficit to calculate evapotranspiration. We all know how smart and trendy fellow he is. If you are at a dry air site, minimum temperatures will be higher, sometimes much higher than the dew point temperature and so the relationship needs to be adjusted to account for this difference. Y AXIS = Minimum Temperature - Dew Point Temperature CED Graph 20 |....#####....................................................... |.....####.....#.................................................. |......####....................................................... |.......####...................................................... |........####..................................................... 15 |.........####.................................................... |.........#####...#.............................................. |..........#####.................................................. |...........#####................................................. |............######................................................ 10 |...........#.######............................................. |..............#######............................................ |.............#.#######..#........................................ |................#######......................................... |.................########........................................ 5 |...................#######....................................... |.....................#######....#................................ |.................#....#######................................... |...................#..#.########.......#........................ |........................#...######.............................. 0 +----|----|----|----|----|----|--##|####|###|####|####|----|----| 0 10 20 30 40 50 60 70 80 90 100 AVERAGE Monthly % RELATIVE HUMIDITY Estimates dewpoint temperature in dry areas using minimum temperatures is possible. The graph above is a CED sketch graph representing 1000+ data points(stations from all over the dry world). If you know your average monthly % relative humidity and your minimum temperature you can use this graph to find an estimate of Tmin-Td and thus Td! It would be better, however to collect daily Tmin and daily Td data from your nearest class A weather station (or your LTER network station if it is a good long record) and build a chart for your site. I did it for Richmond, Virginia using LCD publication [Local Climate Data) of NOAA NCDC, Asheville, NC. The graph using daily data not monthly is of the same form but is not so messy as with monthly data and the equation for the curve is (Tmin-Td) = 61.38 -30.57*Log(Relative Humidity) R^2 = 0.985. Not bad! With these figures, we introduce CED graphs. These graphics are limited in resolution by the E-mail type and line spacing. We will do the best we can in putting points in just about the proper location and we will give the equations fit to the data when possible. Comments on CED graphs will help us do better next time. Technology will, "for sure", make CED graphs obsolete someday. ***************************************************************** ***************************************************************** *** *** *** Dateline LTER CC meeting *** *** *** *** OZONE HOLE OVER TROUT LAKE *** *** *** ***************************************************************** ***************************************************************** Three people approached me at the Trout Lake meeting about their concerns over NASA's chlorine monoxide press release! I knew I was sent to the meeting for a purpose. I told them that the Canadians had published in Nature (Jan. 9, 1992) that the source of ClO and BrO in the Arctic was ocean water and Pinatubo halogens. I also mentioned that there are 1950s vintage textbook charts of ozone concentrations in the Northern hemisphere by latitude and month and that there was an "ozone hole" in winter even then. I told them not to worry about a bad sunburn out on Trout Lake. The best time of the year for an ozone hole is winter when the sun is shining on the southern hemisphere. Well, while most of us were winging our way to Trout Lake, the fan got hit. Over the past few weeks NASA has sprung leaks. Headlines should read: LEAKING SCIENTISTS AT NASA! The results of all that LEAKING even reached Charlottesville, Virginia. Apparently, they sent up another plane on the trail of the chlorine monoxide that would make an ozone hole over the high latitudes this winter and put Trout Lake goers in peril. There were few suntans earned at Crystal Lake to say nothing of the cute bog we visited. Well, the NASA plane went up again (post press release) and had a devil of a time finding the chlorine monoxide. NASA satellites also had trouble finding the ozone killing chlorine monoxide. NASA O3 PIs had to go public. The LEAKERS won. Joe Waters Project PI out of Cal Tech said the satellites said that the chlorine monoxide had gone down since January to one third of its former self. The aircraft measurements confirmed the low chlorine monoxide values. O3 Satellite PI Kurylo admitted that "there won't be a large ozone hole this year." Apparently one day of high ClO or BrO doesn't an ozone hole make. Remember when the news-release-before-publication, highest-ever-cholrine monoxide story broke on February 3. Chicken Littles, much practiced these days, ran everywhere. Environmental President Bush, through the politically correct lips of EPA Reilly, was "very concerned" and would likely move up the date to phase out chlorofluorocarbons. Not to be outdone, the Senate voted 96-0 to ban the chemicals as soon as possible! The sky was rumored to be falling on February 3. As to news-release-before-publication method, Brian Dunbar of NASA played the role of spin doctor and said the reason for the release was "because there's so much public interest." The system "worked the way it was supposed to -- we provide the information and the policy makers made their decision." It is so nice to be Hubbled every once in a while by NASA. Sorry about the length of this item, but it is hard to stop when you are having fun. It's more fun than that, Hayden ***************************************************************** ***************************************************************** *** *** *** *** *** Spencer & Christie Data for LTER *** *** *** *** *** ***************************************************************** ***************************************************************** NASA is now into its 14 year of measuring surface temperatures from satellite. The readouts are for average monthly temperatures in 2.5 lat by 2.5 lon grid cells. They claim the readings are correct to within 0.01 C! We have obtained the data set for 13 years (through 1991). This covers the life spans of all LTERs. We, in the name of the LTER Climate Committee, are in the process of pulling the data from the tapes for each LTER site including Palmer Station. We will put the data in the Network Office Climate archives and each LTER can pull their station data when ready for it. Network office will send out a notice to each site when the data becomes available. The satellite measures therm microwave emissions from oxygen molecules at four frequencies near 60 GHz. Since oxygen concentrations do not vary very much the emissions are related to the average molecular velocity of the oxygen molecules , i.e. the average temperature of the air. For those of you who want to get a leg up on the literature the Spencer & Christie citations follow: Spencer, R. W. and J. R. Christy 1990. Precise Monitoring of Global Temperature Trends from Satellites. Science 247:1558-1562. Spencer & Christie will come as anomalies from the 13 year mean in each lat/lon grid cell. Y AXUS = Satellite T Anomaly (C) CED Graph |................................................................. |................................................................. |................................................................. 2 |................................................................. |................................................................. |...........................................#..................... |..............................................#.................. 1 |....................................#..#......................... |.................................#...#........................... |................................#.#.............................. |.............................#.#...#............................. 0 |..........................##.#................................... |......................#..###.#................................... |.......................##........................................ |............#.....#...#.#........................................ -1 |...................#............................................. |................................................................. |..............#.................................................. |................................................................. -2 |.........#....................................................... +----|----|----|----|----|----|----|----|----|----|----|----|----| -4 -2 0 2 4 6 Surface Thermometer Anomaly (C) This is a CED sketch of S&C's Figure 4. The regression coefficient was 0.89. The S&C data is actually for the lower troposphere rather that a measure of ground temperatures and so the extremes of daily max and mins are filtered out. The data we are getting from S&C is their 2R set which is specially selected for the lower troposphere and has the best relationship to surface data and outstanding correlation with radiosonde measurements. The next issue of CED will fill in more details on this data set and let you know when you can get your LTER site hands on it. ***************************************************************** ***************************************************************** *** *** *** *** *** Isotopically heavy Carl Bowser Contributes *** *** *** *** *** ***************************************************************** ***************************************************************** According to Bowser, the loss of water molecules by evaporation (sweat, evapotranspiration, perspiration and gender specific "glowing") leaves behind a enriched population of heavy water molecules. Bowser's work with Joel Gat at NTL LTER focused on the consequences of a chain of evaporative events to find the limits on this enrichment of heavy water molecules. Relative humidity of the air seems to be the policeman on this beat. I am sure that former French nationals sojourning on Devil's Island might have suspected high relative humidity right off but for North Woods lake people to come to this conclusion through elegant modeling of chained evaporation steps is worthy of note and an LTER readership bent of finding measurement and modeling techniques to quantify critical ecosystem processes. LTERs with hydrological balance shortfalls due to their low ratios of vapor pressure to saturation vapor pressure, should look to the isotopic signature of chained evaporation steps as a useful dynamic. CED recommends Gat and Bowser's paper J. R. Gat and C. Bowser 1991. "The heavy isotope enrichment of water in coupled evaporative systems" Stable Isotope Geochemistry: A Tribute to Samuel Epstein. The Geochemical Society Special Publication (#3:159-168) ***************************************************************** *************** NEXT CED IN ABOUT 1 MONTH ************ ***************************************************************** BRUCE P HAYDEN bph@envsci.acc.virginia.edu