CONTENTS 7
Preface 17
Contributors 19
1. Introduction 25
2. General Oceanography of the Baltic Sea 29
2.1 Specific Natural Conditions and Their Consequences 29
2.2 Estuarine Circulation 35
2.2.1 Long-Term Exchange 35
2.2.2 Short-Term Barotropic Exchange 36
2.2.3 Stratification and Mixing in the Channels 42
2.2.4 Quantifying the Stochastic Salt Exchange Associated with the Barotropic Water Exchange 44
2.3 Wind-Driven Currents 46
2.3.1 Ekman Current and Transport 46
2.3.2 Upwelling and Coastal Jets 48
2.4 Surface Waves, Tides, Seiches, Surges 50
2.4.1 Surface Gravity Waves 50
2.4.2 Seiches and Wind Stau 52
2.4.3 Tides 53
2.5 Kelvin Waves, Topographic Waves, and Eddies 55
2.5.1 Kelvin Waves 55
2.5.2 Coastal Trapped Waves and Continental Shelf Waves 56
2.5.3 Eddies 58
2.6 Internal Waves, Turbulence, Diapycnal Mixing 59
2.6.1 Introduction 59
2.6.2 Vertical Mixing in the Interior 60
References 63
3. The History of Long-Term Observations in Warnem眉nde 69
3.1 Introduction 69
3.2 Shipborne Measurements at Fixed Stations 70
3.2.1 Basic Oceanographic Instrumentation for Shipborne Measurements 70
3.2.2 Oceanographic Observations in the 1950s and 1960s 71
3.2.3 International Cooperation 1969\u20132005 73
3.2.4 Activities in the Frame of BMP, 1979\u20132005 74
3.3 Buoy Stations and Measuring Platforms 76
3.3.1 The First Buoy Stations 77
3.3.2 MARNET Stations 77
3.3.3 Current Meter Stations in the Central Baltic Sea 79
3.4 Parameters Measured 80
3.5 Data Quality 80
References 81
4. Weather of the Baltic Sea 89
4.1 Introduction 89
4.2 Extreme Weather Conditions 90
4.2.1 Hurricanes, Gales 90
4.2.2 Storm Surges 95
4.2.2.1 Features of the Northwest Situation 97
4.2.2.2 Features of the Northeast Situation 98
4.3 Special Weather Situations 100
4.3.1 Baltic Cyclones 100
4.3.2 Land and Sea Breeze 103
4.3.3 Warnem眉nder Wind 105
4.3.4 General Vb- and Omega-Weather Types 108
4.3.4.1 The Vb-Weather Type 108
4.3.4.2 The Omega-Weather Type 110
4.4 Greenhouse Effect 111
Acknowledgment 114
References 114
5. Baltic Climate Change 117
5.1 Introduction 117
5.2 Seasonal Cycles 118
5.3 Climatic Trends 125
5.4 Climatic Variability 129
5.4.1 Year-to-Year Fluctuations 129
5.4.2 Decadal Scale Changes 133
5.4.3 Possible Trigger Mechanisms 137
5.5 Conclusions and Outlook 140
References 141
6. Current Observations in the Western Baltic Sea 145
6.1 Introduction 145
6.2 Great Belt and Fehmarnbelt 147
6.2.1 Great Belt 147
6.2.2 Fehmarnbelt 150
6.3 Arkona Sea West and Drogden Sill 153
6.3.1 Darss Sill 154
6.3.2 Drogden Sill 155
6.3.3 From Kriegers Flak to Hiddensee 156
6.4 Around R眉gen 158
6.4.1 West Off Hiddensee 158
6.4.2 Wittow 159
6.4.3 Kap Arkona 160
6.4.4 Tromper Wiek 161
6.4.5 From Landtief A to Jan Heweliusz 161
6.4.6 Oderbank 163
6.5 Conclusions 164
Acknowledgments 164
References 164
7. Sea State, Tides 167
7.1 Sea State 167
7.1.1 History of Observation and Research 167
7.1.2 Observation and Measurement 170
7.1.3 Sea State Characteristics and Wave Generating Factors 170
7.1.3.1 Wind Sea Characteristics 171
7.1.3.2 Wave Height Frequency Distribution 174
7.1.3.3 Wave Spectra 175
7.1.3.4 Wave Generating and Wave Modifying Factors (Wind, Fetch, Wind Duration, Water Depth) 176
7.1.3.5 Special Phenomena (Air-Sea Temperature, Currents, Crossing Seas) 180
7.1.4 Calculation and Forecast of the Sea State 182
7.1.4.1 Empirical Wave Parameter Calculation 183
7.1.4.2 Empirical Wave Spectra 185
7.1.4.3 Numerical Models 186
7.1.5 Wave Climatology 188
7.1.5.1 Open Sea Wave Climate 189
7.1.5.2 Wave Climate of the Coastal Zone 199
7.1.6 Extreme Wave Conditions 202
7.2 Tides 205
7.2.1 History of Tidal Research in the Baltic Sea 208
7.2.2 Theory of Tides in the Baltic Sea and a Proper Model Concept 209
7.2.3 Modeling of Co-Oscillating and Direct Tides 214
Acknowledgment 217
References 217
8. Ice 223
8.1 Introduction 223
8.2 The Baltic Sea and Winter Time Maritime Transportation 225
8.3 Frequency of Ice Occurrence in the Baltic Sea as Well as Mean and Extreme Ice Parameters from Representative Stations in the Period 1956\u20132005 231
8.4 Ice Conditions in the Baltic Sea and Adjacent Waters in 1956\u20132005 236
8.4.1 Transition Area between the North Sea and Baltic Sea 236
8.4.1.1 Skagerrak and Kattegat 236
8.4.1.2 Belts and Sound 238
8.4.2 Western Baltic 238
8.4.3 Southern Baltic 239
8.4.4 Northern Baltic 243
8.4.5 Gulf of Riga 244
8.4.6 Gulf of Finland 245
8.4.7 Gulf of Bothnia 246
8.4.7.1 Sea of 脜land 248
8.4.7.2 Archipelago Sea 248
8.4.7.3 Sea of Bothnia 249
8.4.7.4 Bay of Bothnia and the Quark 249
8.5 Classification of Ice Winters 249
8.5.1 Maximum Extent of Ice Coverage in the Baltic Sea 1720\u20132005 249
8.5.1.1 Material 249
8.5.1.2 Classification of Ice Coverage 250
8.5.1.3 Analysis of Time Series 250
8.5.1.4 Ice Seasons 1956\u20132005 252
8.5.2 Ice Winter Severity Indicator\u2014Swedish Coast 252
8.5.3 Ice Winter Severity Indicator for the Southern Baltic Sea 253
8.5.4 Accumulated Areal Ice Volume for the Western Baltic Sea 255
8.5.5 Changes of Sea Ice Conditions in the Western Baltic from 1300 to Present 258
References 262
9. Satellite-Derived Sea Surface Temperature for the Period 1990\u20132005 265
9.1 Introduction 265
9.2 Methodology 267
9.3 Seasonal, Regional, and Interannual Variations of SST in the Baltic Sea 270
9.4 Trends in the Development of SST 276
9.5 Relation to Climate Indices 280
9.6 Regional Particularities in SST Patterns 282
9.6.1 Upwelling and Other Dynamical Features in the Baltic Sea 282
9.6.2 Oder River Discharge and Oder Flood 284
9.6.3 Coastal Wind-Driven Processes along the German Baltic Sea Coast 284
9.7 Summary and Conclusions 285
Acknowledgment 286
References 286
10. The Inflow of Highly Saline Water into the Baltic Sea 289
10.1 Introduction 289
10.2 The Causes of MBIs and Their Basic Impact on the Baltic Sea 290
10.3 The Statistical Analysis of Major Baltic Inflows 296
10.4 The Analysis of Selected Events 304
10.4.1 MBIs in the 1950s and 1960s 304
10.4.2 The 1970s 305
10.4.3 The Very Strong MBI in January 1993 307
10.4.4 The Warm Water MBI in Autumn 1997 308
10.4.5 The Specific MBI in January 2003 310
10.5 The Analysis of Baroclinic Summer Inflows 311
10.6 The Effects of MBIs and Baroclinic Summer Inflows in the Central Baltic Deepwater 314
10.6.1 The Effects on the Hydrographic Parameters Temperature, Salinity, and Oxygen Concentration 314
10.6.2 The Effects on Inorganic Nutrients 320
References 326
11. BALTIC: Monthly Time Series 1900\u20132005 335
11.1 Introduction 335
11.2 Data Material 338
11.3 Quality Control and Uncertainties 339
11.3.1 IOW Data 344
11.3.2 SMHI Data 345
11.3.3 NERI Data 347
11.3.4 IMGW Data 349
11.3.5 Additional Data 349
11.4 Monthly Time Series 1900\u20132005 351
References 356
12. Nutrient Concentrations, Trends and Their Relation to Eutrophication 361
12.1 Introduction 361
12.2 Nutrient Inputs 363
12.3 Annual Inorganic Nutrient Cycles and Long Term Nutrient Trends in the Surface Layer 364
12.4 Inorganic Nutrient Reservoirs in the Deep Basins 370
12.5 Organic Nutrients 376
12.6 Conclusions 386
References 387
13. Trace Metals in Baltic Seawater 391
13.1 The State of Knowledge until 1993 391
13.2 Trace Metal Trends in the Western and Central Baltic Sea Between Saltwater Inflow Events in 1993 and 2003 396
13.3 The Influence of Major Saltwater Inflow Events and Stagnant Anoxic Deepwater Conditions on Trace Metal Trends in the Gotland Deep 401
13.3.1 Pb, Cd, Cu, and Zn Trends \u201cAbove and Below Halocline\u201d 402
13.3.2 Quantification of Trace Metal Fluxes across the Redox Interface Caused by Vertical Turbulent Mixing 403
13.3.3 The Relation between External and Internal Fluxes 405
13.4 Seasonal Particulate Trace Metal Fluxes across the Halocline in the Water Column of the Eastern Gotland Basin 406
13.4.1 Composition of Particles 407
13.4.2 Mass Fluxes of Main Components and Trace Metals 407
13.5 Flux and Budget Estimations of Cd, Cu, Pb, and Zn in the Surface Water of the Central Baltic Sea 410
13.6 Outlook 412
Acknowledgment 413
References 413
14. Sedimentary Records of Environmental Changes and Anthropogenic Impacts during the Past Decades 419
14.1 Changing Coastlines of the Baltic Sea 419
14.1.1 Introduction 419
14.1.2 The Geological/Tectonic Setting of the Baltic Area 421
14.1.3 Relative Sea-Level Change 422
14.1.4 Palaeogeography\u2014Coastline Change 424
14.1.5 Summary 425
Acknowledgment 426
14.2 Recent Sedimentation in the Eastern Gotland Basin: Spatial Patterns, Rates, and Drivers 428
14.2.1 Introduction 428
14.2.2 Spatial Distribution of Sedimentation Rates 428
14.2.3 Element Accumulation Rates 429
14.2.4 Vertical Versus Horizontal Fluxes of Biogenic Elements 430
14.2.5 Summary 434
14.3 Reconstruction of Pollution History in Sediment Cores from Different Baltic Sea Basins 434
14.3.1 Introduction and Background 434
14.3.2 Field Work and Laboratory Methods 435
14.3.3 Sediment Properties and Age Models 437
14.3.4 Heavy Metals and Organic Pollutants in the Sediment Cores 439
14.3.5 Inventories of Pollutants 443
14.3.6 Summary 445
Acknowledgments 447
14.4 Repeated Geochemical Mapping of the Arkona Basin after 17 Years (1988 and 2005) 447
14.4.1 Introduction 447
14.4.2 Methodology 448
14.4.3 Results 448
14.4.4 General Sedimentology, Hydro- and Sediment Dynamics 449
14.4.5 Redox-Dependent Processes 450
14.4.6 Fe\u2013Mn Microconcretions 453
14.4.7 Pollution (Heavy Metals) 455
14.4.8 Conclusions and Outlook 457
14.4.9 Summary 457
Acknowledgments 458
References 458
15. Phytoplankton 465
15.1 History of Phytoplankton Research and Methodology in the Baltic Sea 465
15.1.1 Quantitative Phytoplankton Analysis 465
15.1.2 Chlorophyll 467
15.1.3 Primary Production and Nitrogen Fixation 468
15.1.4 Satellite Imagery 469
15.2 Factors Influencing Phytoplankton 470
15.3 Spatial Distribution 471
15.3.1 Phytoplankton Composition and Biomass 471
15.3.2 Chlorophyll 473
15.3.3 Primary Production and Nitrogen Fixation 476
15.4 Seasonal Pattern 477
15.4.1 Phytoplankton Succession and Blooms 477
15.4.2 Chlorophyll 482
15.4.3 Primary Production and Nitrogen Fixation 483
15.5 Long-Term Trends 484
15.5.1 Phytoplankton Composition and Biomass 484
15.5.1.1 Spring Bloom 485
15.5.1.2 Summer Bloom 486
15.5.1.3 Autumn Bloom 488
15.5.1.4 Non-Indigenous Phytoplankton 488
15.5.2 Chlorophyll 488
15.5.3 Primary Production and Nitrogen Fixation 490
15.6 Relationship between the Different Phytoplankton Parameters 492
Acknowledgments 492
References 493
16. Macrophytobenthos 507
16.1 Preview 507
16.2 Species Inventory 508
16.2.1 Data Available 508
16.2.2 Definition of the Term \u201cMacrophytobenthos\u201d 508
16.2.3 Taxonomic Problems 508
16.2.4 Species Disappeared from the Baltic Sea 510
16.2.5 Species Invading the Baltic Sea 512
16.3 Developments in the Baltic Sea by Regions 514
16.3.1 Western Baltic\u2014Kattegat, Belt Sea, and the Southern Coast 514
16.3.2 Eastern Baltic Proper Coast and Gulf of Riga 522
16.3.3 Western Baltic Proper Coast and Archipelago/Aland Sea 523
16.3.4 Gulf of Finland and Neva Bay 524
16.3.5 Bothnian Sea and Bay 526
16.4 Summary 527
References 531
17. Zoobenthos 541
17.1 Introduction 541
17.2 How Diverse is the Macrozoobenthos in the Southern Baltic Sea? Analysis of Historical and More Recent (IOW) Data 542
17.2.1 History of Macrozoobenthic Research in the Southern Baltic Sea 542
17.2.2 Investigation Area 543
17.2.3 Literature Sources 545
17.2.4 IOW Data 545
17.2.5 Taxonomy 545
17.2.6 Database 545
17.2.7 Macrozoobenthic Diversity in the Southern Baltic 545
17.3 Macrozoobenthic Patterns and Dynamics in the Southern Baltic Sea at Selected Monitoring Stations during the Past 15 Years 549
17.3.1 Spatial Distribution of Macrozoobenthic Species 551
17.3.2 Temporal Changes in the Macrozoobenthos Distribution in the Southern Baltic 554
17.3.3 Benthic Fauna, Ecological Status and Ecosystem Functions 558
References 561
18. Fish Stock Development under Hydrographic and Hydrochemical Aspects, the History of Baltic Sea Fisheries and Its Management 567
18.1 Introduction 567
18.2 The Cod Story 574
18.3 The Flatfish Story 577
18.4 Effects of Climate- and Fishery-Induced Changes on Baltic Fish Stocks, and Ecosystem Structure 580
18.5 Cod Reproductive Success and Climate-Hydrographic Processes 581
18.6 Sprat and Herring Reproductive Success and Climate-Hydrographic Processes 582
18.7 Climate Effects on Growth 584
18.8 Climate Effects on Species Interactions and Ecosystem Structure 586
18.9 The Potential for a Recovery of the Eastern Baltic Cod Stock and Benefits from a Potentially Reestablished Balanced Ecosystem 588
18.10 Managing into and out of the Clupeid Trap\u2014a Case for Conservation and Baltic Ecosystem Improvement 590
18.11 Influence of Contaminants on Baltic Fish and Fisheries 595
18.12 Summary and Perspective 596
References 597
19. Description of the Baltic Sea with Numerical Models 607
19.1 Introduction 607
19.2 A Model System 609
19.2.1 Circulation Models 609
19.2.2 Biogeochemical Models 613
19.2.3 Model Implementation 614
19.2.3.1 Example of a Baltic Sea Model 614
19.2.3.2 Model Grid and Topography 614
19.2.3.3 Open Boundary Conditions 615
19.2.3.4 Choice of the Horizontal Advection and Diffusion Scheme for Tracers 616
19.2.3.5 Adjustment of the Transport Cross Sections of the Belts 616
19.2.3.6 Sea Ice Model 617
19.2.3.7 Turbulent Vertical Mixing and Viscosity 619
19.2.3.8 Atmosphere-Ocean Fluxes of Matter and Momentum 621
19.2.3.9 Long Wave Radiation Budget 623
19.2.3.10 Solar Radiation in the Atmosphere 623
19.2.3.11 Penetration of Short-Wave Radiation into the Water 624
19.3 Applications of the Model System 624
19.3.1 Simulation of Circulation Patterns in the Transition Area between the Baltic and North Sea 624
19.3.2 River Plumes 625
19.3.3 Pathways of Salt Transports into the Arkona Basin 629
19.3.4 Nutrient Load Experiments and Oxygen Dynamics 630
19.3.5 Transport of Suspended Particulate Matter 633
19.3.6 Long-Term Simulations 636
19.4 Future Challenges 638
19.4.1 Highly Resolving Models 638
19.4.2 Coupled Atmosphere-Ice-Ocean Models 640
19.4.3 Higher Levels of the Food Web 640
19.4.4 Modeling across the Disciplines 641
References 642
20. Digital Supplement 649
20.1 Introduction 649
20.2 General Data 650
20.2.1 Thermodynamic Properties 650
20.2.2 Parameters: Codes, Units, and Conversions 653
20.2.3 Reference Data 658
20.2.4 Digital Shorelines 661
20.2.5 Digital Bottom Topography 661
20.3 Observational Data 667
20.3.1 Climatological Data 667
20.3.2 Ice Data 669
20.3.3 Sea Level Data 671
20.3.3.1 Sea Level at Landsort 672
20.3.3.2 Sea Level at Gedser and Hornb忙k 675
20.3.3.3 German Gauge Data 677
20.3.4 River Discharge Data 678
20.3.5 BALTIC Atlas Data 679
20.3.6 Inflow Data 680
20.3.7 Irradiation Data 683
20.3.8 Phytoplankton Data 684
20.4 Figures of the Book 686
Acknowledgment 686
References 686
21. Summary and Outlook 693
Appendix 703
List of Abbreviations 703
Index 711