Artificial Ice Research Articles

Ice And The Origin Of Life

Sea ice occurs abundantly at the polar caps of the Earth and, probably, of many other planets. Its static and dynamic properties that may be important for prebiotic and early biotic reactions are described. It concentrates substrates and has many features that are important for catalytical actions. We propose that it provided optimal conditions for the early replication of nucleic acids and the RNA world. We repeated a famous prebiotic experiment, the poly-uridylic acid-instructed synthesis of polyadenylic acid from adenylic acid imidazolides in artificial sea ice, simulating the dynamic variability of real sea ice by cyclic temperature variation. Poly(A) was obtained in high yield and reached nucleotide chain lengths up to 400 containing predominantly 3'--> 5' linkages.

Emperor penguins adjust swim speed according to the above-water height of ice holes through which they exit

Emperor penguins leap from the water onto the sea ice. Their ability to reach above-water height depends critically on initial vertical speed of their leaping, assuming that the kinetic energy is converted to gravitational potential energy. We deliberately changed the above-water heights of ice hole exits, in order to examine whether penguins adjusted swim speed in accordance with the above-water height of the ice. Penguins were maintained in a corral on the fast ice in Antarctica, and voluntarily dived through two artificial ice holes. Data loggers were deployed on the penguins to monitor under water behavior. Nine instrumented penguins performed 386 leaps from the holes during experiments. The maximum swim speeds within 1 s before the exits through the holes correlated significantly with the above-water height of the holes. Penguins adopted higher speed to exit through the higher holes than through the lower holes. Speeds of some failed exits were lower than the theoretical minimum values to reach a given height. Penguins failed to exit onto the sea ice in a total of 37 of the trials. There was no preference to use lower holes after they failed to exit through the higher holes. Rather, swim speed was increased for subsequent attempts after failed leaps. These data demonstrated that penguins apparently recognized the above-water height of holes and adopted speeds greater than the minimal vertical speeds to reach the exit height. It is likely, especially in the case of higher holes (>40 cm), that they chose minimum speeds to exit through the holes to avoid excess energy for swimming before leaping. However, some exceptionally high speeds were recorded when they directly exited onto the ice from lower depths. In those cases, birds could increase swim speed without strokes for the final seconds before exit and they only increased the steepness of their body angles as they surfaced, which indicates that the speed required for leaps by emperor penguins were aided by buoyancy, and that penguins can sometimes exit through the ice holes without any stroking effort before leaping.

Application of micro-X-ray fluorescence to chemical mapping of polar ice

AbstractSynchrotron-based micro-X-ray fluorescence (μXRF) equipment has been used to analyze impurities in polar ice. A customized sample holder has been developed and the μXRF equipment has been adapted with a thermal control system to keep samples unaltered during analyses. Artificial ice samples prepared from ultra-pure water were analyzed to investigate possible contamination and/or experimental artefacts. Analyses of polar ice from Antarctica (Dome C and Vostok) confirm this μXRF technique is non-destructive and sensitive. Experiments can be reproduced to confirm or refine results by focusing on interesting spots such as crystal grain boundaries or specific inclusions. Integration times and resolution can be adjusted to optimize sensitivity. Investigation of unstable particles is possible due to the short analysis time. In addition to identification of elements in impurities, μXRF is able to determine their speciations. The accuracy and reliability of the results confirm the potential of this technique for research in glaciology.

Innovations on thin ice

Sport is becoming increasingly important in contemporary society and has grown into a multi-billion dollar business. This paper analyzes improvements in performance in one particular sport, speed-skating, and compares the results with theories used to describe or characterize innovations in a commercial industrial environment. The Henderson and Clark architectural methodology is particularly suited to speed skating because improvements in performance in the sport are the result of a combination of the skater's ability, the equipment used and other ‘environmental’ factors. The klapskate, skinsuit, artificial ice and indoor rinks can all be identified as components and factors having a quantifiable effect in the ‘market’. Because of their full penetration into the market, they can be categorized as ‘dominant designs’, referring to the concept introduced by Abernathy and Utterback. Based on statistical analyses of world records, we distinguished four innovation sub-processes that were additive to a long-term improvement process. The analysis shows that there is still considerable potential for improvement in performance levels in speed skating through innovation.

Dynamic modeling of de arc discharge on ice surfaces

A dynamic model for predicting DC arc behavior and critical flashover voltage of ice-covered insulating surfaces is presented. The model takes into consideration insulating geometry, pre-contamination level, and characteristics of ice layers. Assuming arc behavior as a time dependant impedance, it is possible to determine various arc characteristics such as time histories of leakage currents, potential gradient, channel radius, trajectory, propagation velocity and the energy injected into the zones free of ice (also called air gaps). The simulated results provided by the model are in agreement with those obtained experimentally using a simplified ice-covered cylinder as well as a short string of five IEEE standard porcelain suspension units covered with artificial ice.

Ultrasonic Frost Suppression

The authors have observed the accumulation of frost on the surface of a rectangular aluminum alloy (duralumin) plate flexurally vibrating at approximately 37 kHz in an atmosphere of almost 100% relative humidity at 2°C. The plate surface, which had been prepolished with abrasive slurry for maintaining its average surface roughness of about 100 nm, was refrigerated at a temperature of -20°C with cold carbon-dioxide gas as coolant. Experiments have been conducted with and without fine silver oxide powder spread on the plate surface so as to examine the effect of artificial ice crystal nuclei. Ultrasonic vibrations with an amplitude of 3.4 µm (rms) are found to suppress frost accumulation by approximately 60%. The phenomenon cannot be ascribed directly to the heat generation caused by high-amplitude vibration, but may have a complex mechanical and/or acoustical effect on small ice crystals.

Determination of Sodium in Artificial Ice Samples by Laser Ablation/Laser Induced Fluorescence Technique

Determination of Sodium in Artificial Ice Samples by Laser Ablation/Laser Induced Fluorescence Technique

A mesocosm study of physical-biological interactions in artificial sea ice: effects of brine channel surface evolution and brine movement on algal biomass

The impact of changing physico-chemical boundary conditions in sea ice on biological processes was investigated during a 20-day-long simulated freeze-melt cycle in an 180-m3 mesocosm filled with artificial seawater and addition of a mixed Arctic sea-ice community. Ice formation started at Tair of –15°C with a growth rate of 0.7–1.2 mm h–1 for 10 days. The last 10 days (Tair of=–5°C), ice thickness remained around 20 cm. Ice temperature gradients inside the ice were linear and determined brine salinities. Brine was collected by means of centrifugation and its volume ranged from 5 to 30% of total ice volume. Surface areas of interconnected brine channels were determined with two similar techniques and maximum values ranged between 1.5 and 4.8 m2 kg–1ice. Measurements determined with a modified method varied considerably and differed by a maximal factor of 2.0–6.5. Brine channel surfaces increased during the experiment as a result of the warming of the ice. The inoculated algal community was dominated by flagellates <10 µm. The low diatom biomass increased in the ice after the air temperature rise with rates comparable to field data (µ=0.2–0.3 day–1). Comparison with brine salinities points towards the hypothesis of vertical brine stability being a controlling factor for ice algal growth. We infer from brine channel surface measurements that persistence of brine channel surfaces during spring might be an important prerequisite for the commencement of net diatom biomass accumulation. Advantages and limitations of mesoscale mesocosms as alternatives in ice biological work are discussed.

Modelling of DC arc discharge on ice surfaces

Using a triangular ice sample, the characteristics of the DC arc appearing on ice surfaces was investigated. Based on the results obtained, a model for predicting the 50% flashover voltage of ice-covered insulators energised with DC was presented. The model takes into account the ice surface conductivity, voltage polarity, and arc root radius. Moreover, to validate the model, the 50% flashover voltage of a short string of five IEEE standard insulators covered with artificial ice under both DC– and DC+ was measured. There was an excellent concordance between the experimental results and those calculated from the mathematical model.

Multiple-hydrologic stressors of a northern delta ecosystem

During the early 1990's, two major ecosystems assessments weremade of the Peace-Athabasca-Delta (PAD), Canada, one of the world'slargest freshwater deltas. The Northern River Basins Study focussed onevaluating the effects of regulation on the Peace-Athabasca Delta,whereas the Peace-Athabasca Delta Technical Studies considered optionsfor restoring the role of water to the PAD. Both programs were initiatedbecause of concern over the health of this important northern aquaticsystem brought about by almost two decades of dry conditions.Recognizing the importance of water to restoring and maintainingbiological productivity and diversity of the PAD, a series of studieswere initiated to explain the reasons for the protracted drying and todesign methods to restore flooding. This manuscript examines the role offlow regulation as a hydrologic stressor affecting the Delta ecosystemand the results of studies that led to the definition of an additionalhydrologic stressor, climate variability. The suitability of adaptationstrategies, such as rock-filled weirs, artificial ice jams, and enhancedflow releases to deal with these multiple stressors are also reviewed.The results also reinforce a need for including river-ice processes intostudies and theories of large-river ecology.

Raman scattering and neutron-diffraction studies of fresh ice and Antarctic ice

AbstractIn order to investigate the temperature dependence of vibrational spectra of ice, we measured the Raman spectra of artificial ice Ih in the temperature range 198–270 K. The frequency of translational lattice vibrations decreases with increases in the measurement temperature, and the rate of decrease discontinuously changes at 237 K. The discontinuous change of the rate of decrease is consistent with the phase transition from a proton-disordered arrangement to a proton-ordered arrangement at the ice temperature Ti = 237 K in polar ice sheets, as proposed by Fukazawa and others (1998b). We then compared the Raman spectra of translational lattice vibrations in ice Ih and Antarctic ice and examined the possible effects of the phase transition on the geophysical properties of Antarctic ice. We also report preliminary results of the neutron powder diffraction of Dome Fuji (DF) Antarctic ice, and discuss arrangements of protons in DF ice.

The bearing capacity of saline ice sheets: centrifugal modelling

Artificial sea ice sheets have been frozen in a centrifuge using novel techniques which yield reproducible ice growth rates and result in ice sheets of uniform thickness. The upper surface of these ice sheets has been subjected to an increasing load applied over a limited area, the maximum sustained load giving the bearing capacity at high inertial acceleration. Such centrifugal modelling techniques produce ice sheets with bearing capacities in agreement with existing field and laboratory data. In particular, the influence of indentor diameter and loading rate is examined and the centrifuge data are found to behave in the same manner as existing data with respect to both of these variables. All data are compared with a number of theoretical descriptions of bearing capacity, and these comparisons are discussed with regard to their impact on the applicability of the centrifuge modelling technique on ice penetration problems.Key words: centrifugal modelling, sea ice, bearing capacity.

Fracturing of ice under compression creep as revealed by a multifractal analysis

Fracturing of freshwater granular ice up to failure under uniaxial compression creep was investigated from series of interrupted creep tests and from a multifractal analysis of the corresponding fracture patterns. At the early stages of damage corresponding to primary and secondary creep, the fracturing process is dominated by the nucleation of microcracks from stress concentrations within the material (unlike rocks, artificial freshwater ice does not contains starter flaws). Because of the crack nucleation mechanisms, the microstructure of the material (e.g., the nonfractal grain size distribution) strongly influences the organization of fracturing which is therefore nonfractal. As fracturing proceeds during tertiary creep, a hierarchical (fractal) organization of the fracturing emerges progressively over a wider scale range. At failure, this fractal organization is fully developed without detectable lower or upper bound, and the role of the initial microstructure has completely disappeared. Similarly, cracks are preferentially oriented along the compression axis at the early stages of damage, but this anisotropy vanishes as failure is approached. The simultaneity between the onset of tertiary creep and the emergence of fractal organization suggests that the acceleration of the deformation during tertiary creep is due to the cataclasis of a material which becomes granular. An important consequence of the fractal organization of fracturing is that homogenization procedures, as well as damage mechanics, developed to study the behavior of damaged materials, cannot be used to describe tertiary creep and failure.

Sea‐salt aerosol in coastal Antarctic regions

Continuous year round records of atmospheric sea‐salt concentrations have been recovered at three coastal Antarctic stations (Halley, Dumont D'Urville, and Neumayer) at temporal resolutions typically between 1 day and 2 weeks. The records were evaluated in terms of their spatial and seasonal variability as well as with respect to changes in the relative ion composition of airborn sea‐salt particles. Annual mean sea‐salt concentrations vary between 1400 ng m−3 at Dumont D'Urville, 850 ng m−3 at Neumayer, and 200 ng m−3 at Halley, respectively. They are thus considerably lower than the mean levels previously observed at the north tip of the Antarctic Peninsula but are, at their lower end, comparable to the level previously reported from Mawson. The representativeness of the atmospheric sea‐salt data appears to be weak due to their high temporal variability, strong impacts of site specific aspects (such as site topography) but also due to the nonuniform sampling techniques applied so far. In accordance with the ice core evidence, the seasonal change in the atmospheric sea‐salt load is found to be clearly out of phase with the seasonal cycle of the open water fraction offshore from the station as (with the exception of Dumont D'Urville) the lowest concentrations are generally observed during the local summer months. Major ion analyses of bulk aerosol and concurrently sampled fresh snow show a strong, systematic depletion of the SO42− to Na+ (Cl−) ratios with respect to bulk sea water, which appeared to be confined to the local winter half year. During that time, sea‐salt SO42− was found to be depleted typically by 60–80% along with a concurrent Na+ deficit, which is in accordance with the precipitation of mirabilite. No significant fractionation of Mg2+, K+, and Ca2+ between seawater and sea‐salt particles is observed. Laboratory experiments failed to simulate the SO42− fractionation in airborne seawater droplets or in the skin of seawater bubbles at low air temperatures. They gave, however, SO42− depletion factors, similar to the field observation in air and snow, in the remaining brine of seawater which was partly frozen below −8°C to an artificial sea ice surface. It is suggested therefore that the mobilization of brine from the sea ice surface constitutes an important sea‐salt source in winter which may dominate the atmospheric sea‐salt load at high latitudes of coastal Antarctica.

Inverse electromagnetic scattering models for sea ice

Inverse scattering algorithms for reconstructing the physical properties of sea ice from scattered electromagnetic field data are presented. The development of these algorithms has advanced the theory of remote sensing, particularly in the microwave region, and has the potential to form the basis for a new generation of techniques for recovering sea ice properties, such as ice thickness, a parameter of geophysical and climatological importance. Moreover, the analysis underlying the algorithms has led to significant advances in the mathematical theory of inverse problems. In particular, the principal results include the following. (1) Inverse algorithms for reconstructing the complex permittivity in the Helmholtz equation in one and higher dimensions, based on layer stripping and nonlinear optimization, have been obtained and successfully applied to a (lossless) laboratory system. In one dimension, causality has been imposed to obtain stability of the solution and layer thicknesses can be obtained from the recovered dielectric profile, or directly from the reflection data through a nonlinear generalization of the Paley-Wiener theorem in Fourier analysis. (2) When the wavelength is much larger than the microstructural scale, the above algorithms reconstruct a profile of the effective complex permittivity of the sea ice, a composite of pure ice with random brine and air inclusions. A theory of inverse homogenization has been developed, which in this quasistatic regime, further inverts the reconstructed permittivities for microstructural information beyond the resolution of the wave. Rigorous bounds on brine volume and inclusion separation for a given value of the effective complex permittivity have been obtained as well as an accurate algorithm for reconstructing the brine volume from a set of values. (3) Inverse algorithms designed to recover sea ice thickness have been developed. A coupled radiative transfer-thermodynamic sea ice inverse model has accurately reconstructed the growth of a thin, artificial sea ice sheet from time-series electromagnetic scattering data.

AC and switching impulse performance of an ice-covered metal oxide surge arrester

Artificial ice tests were conducted for the first time with a high voltage metal oxide surge arrester (MOA) consisting of two units in series. The behaviour of the MOA under glaze ice was studied with AC voltage and switching impulse current surges. The AC voltage test results showed that an unevenly ice-coated MOA may be thermally stressed due to the leakage current transition from the ice covering of one unit to the interior of another unit not covered with so much ice. Whether the stressed unit stands up to this situation or not depends on the thermal properties of the unit and the duration of the active arcing period. With impulse current surges, the residual voltage across an ice-covered unit may easily cause a flashover. This leads to a sudden increase in the surge current. With the MOA studied, the current peak was over twice the value of normal operation, which stressed the lower unit operating normally.

Den lysende gas: Etableringen af det danske gassystem 1800–1890 by Ole Hyldtoft

1002 Book Reviews TECHNOLOGY AND CULTURE graphs make it a pleasant read. Especially the advertisements pro­ vide insight into the figures and line of argument for the introduc­ tion of new technologies and into arguments against competing solutions. A good example is the natural ice industry’s campaign against the artificial ice industry, another one the campaign of the early air-conditioning industry. The book introduces new details and it is a fine, thick text, unlike anything previously published on the history of indoor technology. Thus, the book makes a contribution, even if it does not yield many new insights to the specialized histo­ rian of technology. Hans-Liudger Dienel Dr. Dienel runs the Center for Technology and Society at the Technical Univer­ sity, Berlin. He has published a book on refrigeration and thermodynamics in Ger­ many and the United States, 1870-1930 (Ingenieure zwischen Hochschule und Industrie: Kaltetechnik in Deutschland und Amerika, 1870-1930. Gottingen: Vandenhoeck & Ruprecht, 1995). Den lysende gas: Etableringen afdel danske gassystem 1800-1890. By Ole Hyldtoft. Herning, Denmark: Forlaget Systime, 1994. Pp. 252; il­ lustrations, tables, notes, bibliography, appendices, index, sum­ mary in English. (No price given.) In the 19th century, gasworks represented the British technology that was transferred to other countries in packages. The first Danish public gasworks, for example, were financed by British capital and assembled from British components by British technicians and work­ ers to vaporize British coal. Even their business contracts with au­ thorities and customers were copied from British models. The main theme in this book, however, is not the meticulous transfer of tech­ nology but the quick adoption and efficient domestication ofpublic gasworks technology on such a scale that the author regards the whole process as the construction of the Danish national gas system. Practically from the very beginning, Danes rose to the posts of con­ struction engineers and managers of gas utilities. Within just a few years, domestic workshops became capable ofdelivering most of the equipment needed by the gasworks and a sufficiently competent Danish workforce was trained. In the fifteen years from 1853 to 1868, Denmark raised the density of its gasworks almost to the British level. Only three of thirty-one towns with a population over three thousand lacked a public gas­ works. Ole Hyldtoft aims to explain why the Danes were so efficient in developing a successful urban energy system. A comparison to other Nordic countries is striking. By 1890, when the first wave in the construction of gasworks was exhausted, there were forty-two technology and culture Book Reviews 1003 utilities in Denmark, or as many as in Sweden, Norway, and Finland together. The author neglects to emphasize that the scarcity of indigenous energy resources was the fundamental reason why Denmark was forced to use imported fuels and to economize on their use. In the kingdom of chronic energy famine, illuminants were not the only fuels in great demand. From the late 1860s, Danish gasworks were also cokeries; they normally earned 20 to 30 percent of their income by selling coke, which was a widely used fuel in Denmark. Other Nordic countries, in contrast, were able to rely on indigenous fire­ wood more extensively and therefore the demand for solid fossil fuels there was much more modest. In addition, the sales ofcoke and other by-products enhanced the financial well-being of the Danish utilities because their prices remained stable whereas the price of gas gradually decreased. Although the Danes, due to their fair technical training and high level of motivation, proved talented imitators of British and later also German gas equipment, theywere not innovative in gas technol­ ogy. They directed their creative power to organizational innova­ tions. As early as 1862 the price differentiation of gas between light­ ing and heating was invented by a medium-sized Danish gasworks in Nakskov. This trailblazing pricing policy soon spread all over the country and while stimulating the use of gas ovens it also boosted the sales of gas. After many years, the same policy was adopted by gas utilities abroad. The municipally owned gas supply utility was another organiza­ tional innovation that the Danes exploited energetically. The first gasworks of this type was set up...

Heat and Cold: Mastering the Great Indoors by Barry Donaldson, Bernard Nagengast

1000 Book Reviews TECHNOLOGY AND CULTURE are those by W. Bernard Carlson and David Mowery. Carlson notes that in the United States business firms have historically played a key role in transforming technology from abstract design or model into social artifact. He tries to merge the insights of the social-con­ structivists’ approach to technology with economic theory, arguing that firms should not be treated as “single agents.” That is, decisions about technology within firms often reflect competing interests and ideas, and companies’ decisions about technology are the result of internal power struggles. To illustrate, he applies his interest group model to the Thompson-Houston, Edison, and Westinghouse elec­ tric companies. Building a successful technological system not only required the creation and coordination of organizational capabili­ ties; it also required the coordination (or subjugation) ofcompeting ideas and interests. David Mowrey’s essay provides both a masterful review of the his­ tory ofcorporate R & D and new insights into the broad sweep ofthis history from the establishment of the first corporate labs through the present. It explores the internal workings of research laboratories, both within firms and outside of them. And it places laboratories in the context of “national innovation systems,” to use Richard Nel­ son’s valuable phrase. Like several other contributors but more ex­ plicitly than any other, Mowrey argues that the markets-hierarchy distinction should not be drawn too sharply. Firms internalized much R&D, but before 1940 their labs were focused outward. They acted as listening posts and contact points between the firms and their competitors as well as with other parts ofthe innovation system. Mainly because of changes in public policy, those same labs became much more insular and inward focused after 1940, to the detriment of American inventiveness. It is a fitting essay to capture the import of the entire volume, for it looks from the inside out: from the busi­ ness firm that economists have taken for granted, to the larger con­ text of institutions, policies, industries, and markets that the Chandlerian brand of business history has slighted. Kenneth Lipartito Dr. Lipartito teaches in the Department of History at the University of Houston. Heat and Cold: Mastering the Great Indoors. By Barry Donaldson and Bernard Nagengast. Atlanta: American Society of Heating, Refrig­ erating and Air-Conditioning Engineers, 1994. Pp. xxvii+339; il­ lustrations, notes, index. $99.00 (hardcover). This is an illustrated history of heating and refrigeration, pre­ sented on the occasion of the hundredth anniversary of the Ameri­ can Society of Heating, Refrigerating and Air-Conditioning Engi- TECHNOLOGY AND CULTURE Book Reviews 1001 neers (ASHRAE). The society supports and organizes historical work—for instance, collecting interviews with important retired members of the society—and coauthor Bernard Nagengast was a spiritus rector of this work. The book starts in ancient times, then skips the Middle Ages to arrive fairly quickly in the 19th century (p. 30). More than two-thirds of the book is devoted to the period 1870-1930. There are good reasons for this: it was the most innovative period of refrigeration and covers the first steps of air-conditioning. Ice machines became reliable, artificial ice prevailed against natural ice, a little later the refrigerator against the icebox, and at the end of the period the control of humidity and temperature led to the rise of air-condition­ ing. Most present-dayleading companies in the field, the prime mov­ ers, and the engineering associations were founded in this period. The velocity of technological progress, as the authors note, seems to have slowed down since then (p. 309). It normally is superfluous to complain in a review about what has not been written about, but in this case the process by which the heating and cooling industry began to stagnate would have been most interesting for the historian of technology. The book is written by engineers for engineers, unlike the Fest­ schrift of the ASME Heat Transfer Division, edited by Edwin Layton and John Lienhard (1988), which had a true historical approach focusing on the science-technology relation. This book cannot de­ cide about its focus and tries everything at once. It presents many technological solutions, persons, company histories, and important building projects, but the many little...

Survival and Metabolite Accumulation by Seedlings and Mature Plants of Timothy Grass during Ice Encasement

Seedlings often survive ice encasement stress better than mature plants under field conditions. However, in artificial ice encasement experiments with timothy, no significant difference in survival was detected between these two plant groups. At -2 C seedlings accumulated respiration metabolites during ice encasement to higher levels than adult plants on dry weight or protein basis. No specific differences in metabolism between mature and young plants were detected although mature plants accumulated tartarate and acetate which were not detected in seedlings. Timothy plants accumulated ethanol, malate, lactate and CO2 and smaller amounts of propionate and pyruvate while citrate, fumarate and shikimate were at relatively low levels, and malonate was depleted. Therefore, higher survival of ice encased seedlings in field conditions cannot be ascribed to slower respiration rates or to different respiration pathways. Instead, the effect is probably brought about by more open, and thus less compacted soil, generated during seedbed preparation the previous year. This open soil structure imposes less severe oxygen shortage under ice. © 1997 Annals of Botany Company

96/05443 Roll waves in falling films: An approximate treatment of the velocity field

Sport is becoming increasingly important in contemporary society and has grown into a multi-billion dollar business. This paper analyzes improvements in performance in one particular sport, speed-skating, and compares the results with theories used to describe or characterize innovations in a commercial industrial environment. The Henderson and Clark architectural methodology is particularly suited to speed skating because improvements in performance in the sport are the result of a combination of the skater's ability, the equipment used and other ‘environmental’ factors. The klapskate, skinsuit, artificial ice and indoor rinks can all be identified as components and factors having a quantifiable effect in the ‘market’. Because of their full penetration into the market, they can be categorized as ‘dominant designs’, referring to the concept introduced by Abernathy and Utterback. Based on statistical analyses of world records, we distinguished four innovation sub-processes that were additive to a long-term improvement process. The analysis shows that there is still considerable potential for improvement in performance levels in speed skating through innovation.