A5043538683- Ocean Waves and Remote Sensing
- Oceanographic and Atmospheric Processes
- Coastal and Marine Dynamics
- Tropical and Extratropical Cyclones Research
- Geophysics and Gravity Measurements
- Arctic and Antarctic ice dynamics
- Research in Social Sciences
- Underwater Acoustics Research
- Climate variability and models
- Maritime Transport Emissions and Efficiency
- Vehicle emissions and performance
- Meteorological Phenomena and Simulations
- Atmospheric chemistry and aerosols
- Seismic Waves and Analysis
- Scientific Research and Discoveries
- Wind and Air Flow Studies
- Marine and environmental studies
- Icing and De-icing Technologies
- Marine and coastal ecosystems
- Flood Risk Assessment and Management
- Geomagnetism and Paleomagnetism Studies
- Flow Measurement and Analysis
- Infrared Target Detection Methodologies
- Optical Systems and Laser Technology
- Marine and fisheries research
Finnish Meteorological Institute
2013-2022
University of Miami
2016
Woods Hole Oceanographic Institution
2016
Fimlab (Finland)
2003
The dissipation of kinetic energy at the surface natural water bodies has important consequences for many Physical and biochemical processes including wave dynamics, gas transfer, mixing nutrients pollutants, photosynthetic efficiency plankton. Measurements close to obtained in a large lake under conditions strong wind forcing are presented that show layer enhanced exceeding wall values by one or two orders magnitude. authors propose scaling rate based on parameters, conclude breaking waves...
Abstract. There are a large number of geophysical processes affecting sea level dynamics and coastal erosion in the Baltic Sea region. These operate on range spatial temporal scales observed many other regions worldwide. This, along with outstanding long data records, makes unique laboratory for advancing our knowledge interactions between steering climate change context. Processes contributing to include still ongoing viscoelastic response Earth last deglaciation, contributions from global...
Spectra from various wave-growth experiments have been collected into a database, and the data reanalyzed to explain differences in observed growth rates. For one of (Joint North Sea Wave Project: JONSWAP), extensive wind allowed authors perform detailed analysis time history at point moving with group velocity peak wave spectrum. Using average speed this point, removing spectra that according estimate were not measured steady or increasing wind, taking account atmospheric stratification,...
The development of the wave spectrum with fetch in a steady wind has been studied line consecutive buoys Bothnian Sea 1976 and 1979. relationship that was found between dimensionless peak frequency ωm (=ωmU10/g) X̄ (=gX/U102) close to previous observations. energy ¯σ2 (=g2ω2/U104) about twice observed JONSWAP experiment. In saturation range when ¯ω>4 have form S(ω) = αuU10gω−4 where αu=4.5 × 10−3, independent X̄. deviation from Phillips −5 power law could not be explained by influence...
Air‐sea interaction data from a situation with pronounced unidirectional swell have been analyzed. Measurements of turbulence at three levels (10, 18, and 26 m above mean sea level) together directional wave buoy the site Östergarnsholm in Baltic Sea were used. The situation, which lasted for ∼48 hours, appeared aftermath gale. wind direction during turned slowly within 90° sector. Both gale phase over‐water fetch was >150 km. speed typically 4 s −1 . During maximum near or below lowest...
Abstract Recent field observations and large-eddy simulations have shown that the impact of fast swell on marine atmospheric boundary layer (MABL) might be stronger than previously assumed. For low to moderate winds blowing in same direction as waves, propagates faster mean wind. The momentum flux above sea surface will then two major components: turbulent shear stress, directed downward, swell-induced upward. sufficiently high wave age values, wave-induced component becomes increasingly...
Abstract By combining simultaneous data from an instrumented Air–Sea Interaction Spar (ASIS) buoy and a 30-m tower, profiles of wind turbulence characteristics have been obtained at several heights about 1 to 30 m above the water surface during swell conditions. Five cases formed as averages over time periods ranging 2.5 9.5 h, representing quasi-steady conditions, selected. They represent range typical wave age include wind-following cross-swell cases. For relatively large age, profile...
Abstract Atmospheric and surface wave data from several oceanic experiments carried out on the Floating Instrument Platform (FLIP) Air–Sea Interaction Spar (ASIS) have been analyzed with purpose of identifying swell-related effects momentum exchange during near-neutral atmospheric conditions wind-following or crosswind seas. All a pronounced negative maximum in uw cospectra centered at frequency dominant swell np, meaning positive contribution to stress. A similar this is also obtained for...
Abstract Analysis of the turbulent kinetic energy (TKE) budget for five slightly unstable cases with swell has been performed based on measurements mechanical production, buoyancy transport, and dissipation at levels over sea, from 2.5 to 26 m. The time rate change advection TKE were found be small, so residual is interpreted as an estimate pressure transport term (Tp). In two high wave age, Tp a gain all heights. For three smaller loss in below 5–10 m greater heights, where decrease...
Abstract. We analyse changes in meteotsunami occurrence over the past century (1922–2014) Gulf of Finland, Baltic Sea. A major challenge for studying these short-lived and local events is limited temporal spatial resolution digital sea level meteorological data. To overcome this challenge, we examine archived paper recordings from two tide gauges, Hanko 1922–1989 Hamina 1928–1989, summer months May–October. visually inspect to detect rapid variations, which are then digitised compared air...
On the basis of an extensive data set from air‐sea interaction station Östergarnsholm in Baltic Sea, dependence drag on ocean wave state parameters has been studied for near‐neutral conditions. For developing sea, depends age, u * / c p ( friction velocity and phase speed dominant waves), agreement with recent findings over World Ocean, strongly supporting that can be relied upon to give results representative open such conditions, it is demonstrated logarithmic wind law indeed valid. mixed...
The minimum wind speed for wave generation has been investigated in a laboratory wind-wave flume using sensitive slope gauge to measure the initial wavelets about 10 μm high. growth at very low speeds was higher than predicted by viscous shear-flow instability theory. Assuming that is exponential, inception which rate becomes positive can be defined. It occurred (friction velocity) u * ≈ 2 cm/s, somewhat lower 4–5 cm/s However, observed rates were close theory when waves 1 mm. effect of...
Abstract In slanting fetch conditions the direction of actively growing waves is strongly controlled by geometry. The effect was found to be pronounced in long and narrow Gulf Finland Baltic Sea, where it significantly modifies directional wave climate. Three models with different assumptions on coupling between components were used analyze physics responsible for behavior gulf. directionally decoupled model produced at spectral peak correctly when geometry but gave a weaker steering than...
Abstract. The Archipelago Sea (AS) in the Baltic is a complicated fragmented sea area with numerous small islands and islets that are crossed by several deeper straits. functions as major route for both transport leisure activities on well many other forms of blue economy. Even high maritime this area, knowledge currents along deep channels crossing AS has been limited due to lack quality ensured measurements. To enhance general understanding dynamics AS, we have collected analysed 10...