Antti E K Ojala
Biographic Data
| ID | 4130283 |
|---|---|
| NAME | Antti E K Ojala |
| GIVEN NAMES | Antti E K |
| FAMILY NAME | Ojala |
| SIGNATURE | OJALA A E K |
| AFFILIATIONS | Geological Survey of Finland |
| ORCID | 0000-0001-8272-4835 |
| VERIFIED | Yes |
| TOTAL WORKS | 14 |
| TOTAL CITATIONS | 32 |
| AUTHOR COUNT | 14 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2002 |
| LATEST PUBLICATION YEAR | 2025 |
| H-INDEX | 4 |
Varve series cross-correlation and palaeosecular variation from two clay varve basins in western Estonia
Environmental history recorded over the last 70 years in Biển Hồ maar sediment, Central Highlands of Vietnam
A high-resolution, 1250-year long drought record from Ea Tyn Lake, Central Highlands of Việt Nam
An understanding of past climatic variability at regional to local scales is mandatory for a proper evaluation of current and potential future repercussions from global climate change. The Southeast Asian tropics remain severely under-represented in paleoenvironmental and paleoclimatic reconstructions, although a few recent paleoclimate studies evaluated the variability, position and strength of the main Asian monsoon systems at different timesca…
The environment they lived in
Understanding about regional versus local changes in vegetation is critical in answering archaeological questions, in particular at a time when humans are assumed to have caused higher disturbances at local scales rather than regional scales; this is the case during the Neolithic. The aim of this paper is to assess the impact of Neolithic land use on regional and local vegetation dynamics, plant composition and disturbance processes (e.g. fire) i…
Proxy-based 300-year High Arctic climate warming record from Svalbard
We used fossil Chironomidae assemblages and the transfer function approach to reconstruct summer air temperatures over the past 300 years from a High Arctic lake in Hornsund, Svalbard. Our aims were to compare reconstructed summer temperatures with observed (last 100 years) seasonal temperatures, to determine a potential climate warming break point in the temperature series and to assess the significance and rate of the climate warming trend at t…
A 5500-year oxygen isotope record of high arctic environmental change from southern Spitsbergen
The oxygen isotope composition of chironomid head capsules in a sediment core spanning the past 5500 years from Lake Svartvatnet in southern Spitsbergen was used to reconstruct the oxygen isotope composition of lake water (δ 18 O lw ) and local precipitation. The δ 18 O lw values display shifts from the baseline variability consistent with the timing of recognized historical climatic episodes, such as the Roman Warm Period, the Dark Ages Cold Per…
Neolithic land use in the northern Boreal zone
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datin…
Meteorological validation of chironomids as a paleotemperature proxy using varved lake sediments
In order to improve the reliability of climate models in their projections for the future, spatially and temporally detailed paleoclimate proxy data are needed. In this study, we examined annually laminated sediments from Lake Nurmijärvi (Finland) for their fossil Chironomidae assemblages over a time period with available meteorological observational data (since 1830s). In doing so, we correlated chironomid-based inferences of summer air temperat…
The history of settlement on the coastal mainland in Southern Finland. Palaeoecological, archaeological, and etymological evidence from Lohjansaari Island, Western Uusimaa, Finland
Calibrated pollen accumulation rates as a basis for quantitative tree biomass reconstructions
Recent investigations show that the pollen accumulation rate (PAR) of the common tree taxa is directly related to the biomass and, by inference, to the population size of the taxa around the study site. Fossil PAR records preserved in lakes provide therefore a potential proxy for quantitative biomass and population reconstructions. We use the high-resolution PAR records obtained from two accurately dated lake sediment cores in Finland to generate…
History of agriculture in Mikkeli Orijärvi, eastern Finland as reflected by palynological and archaeological data
Integrated varve and pollen-based temperature reconstruction from Finland
A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (summer-winter) reconstructions of past precipitation and temperature fluctuations. Comparing seasonally resolved varve records with pollen-based sum of growing degree-days (GDD) reconstructions from Lake Nautajärvi, we examined the intra-annual nature of climate variability in central southern Finland during the Holocene. The organic varve record and …
Neoglacial activity in Finland
Palaeomagnetic dating of sediment sequences from lakes Pihtsusjärvi and Haltijärvi in Enontekiö, northwestern Finnish Lapland, provided a chronology for a study of the palaeohydrological and glacier history of the Halti-Ridnitšohkka fells area. Both sequences exhibited a stable primary component of the NRM direction, allowing a comparison of the secular variation records with the chronology of Lake Nautajärvi reference curves (NRM) to provide a c…
Palaeosecular variation of the Earth's magnetic field during the last 10000 years based on the annually laminated sediment of Lake Nautäjarvi, central Finland
A palaeomagnetic study of the Lake Nautajärvi sediment sequence in central Finland demonstrates that varved lake sediments can provideregionally applicable secular variations curves for Holocene stratigraphic correlation and age control. Based on x-ray radiography and digital image analysis techniques we constructed an inherent and continuous varve chronology for the Lake Nautajärvi varve sequence, which covers nearly 10000 years with an estimate…
Neolithic land use in the northern Boreal zone
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datin…
Calibrated pollen accumulation rates as a basis for quantitative tree biomass reconstructions
Recent investigations show that the pollen accumulation rate (PAR) of the common tree taxa is directly related to the biomass and, by inference, to the population size of the taxa around the study site. Fossil PAR records preserved in lakes provide therefore a potential proxy for quantitative biomass and population reconstructions. We use the high-resolution PAR records obtained from two accurately dated lake sediment cores in Finland to generate…
The history of settlement on the coastal mainland in Southern Finland. Palaeoecological, archaeological, and etymological evidence from Lohjansaari Island, Western Uusimaa, Finland
Palaeosecular variation of the Earth's magnetic field during the last 10000 years based on the annually laminated sediment of Lake Nautäjarvi, central Finland
A palaeomagnetic study of the Lake Nautajärvi sediment sequence in central Finland demonstrates that varved lake sediments can provideregionally applicable secular variations curves for Holocene stratigraphic correlation and age control. Based on x-ray radiography and digital image analysis techniques we constructed an inherent and continuous varve chronology for the Lake Nautajärvi varve sequence, which covers nearly 10000 years with an estimate…
A high-resolution, 1250-year long drought record from Ea Tyn Lake, Central Highlands of Việt Nam
An understanding of past climatic variability at regional to local scales is mandatory for a proper evaluation of current and potential future repercussions from global climate change. The Southeast Asian tropics remain severely under-represented in paleoenvironmental and paleoclimatic reconstructions, although a few recent paleoclimate studies evaluated the variability, position and strength of the main Asian monsoon systems at different timesca…
The environment they lived in
Understanding about regional versus local changes in vegetation is critical in answering archaeological questions, in particular at a time when humans are assumed to have caused higher disturbances at local scales rather than regional scales; this is the case during the Neolithic. The aim of this paper is to assess the impact of Neolithic land use on regional and local vegetation dynamics, plant composition and disturbance processes (e.g. fire) i…
Meteorological validation of chironomids as a paleotemperature proxy using varved lake sediments
In order to improve the reliability of climate models in their projections for the future, spatially and temporally detailed paleoclimate proxy data are needed. In this study, we examined annually laminated sediments from Lake Nurmijärvi (Finland) for their fossil Chironomidae assemblages over a time period with available meteorological observational data (since 1830s). In doing so, we correlated chironomid-based inferences of summer air temperat…
A 5500-year oxygen isotope record of high arctic environmental change from southern Spitsbergen
The oxygen isotope composition of chironomid head capsules in a sediment core spanning the past 5500 years from Lake Svartvatnet in southern Spitsbergen was used to reconstruct the oxygen isotope composition of lake water (δ 18 O lw ) and local precipitation. The δ 18 O lw values display shifts from the baseline variability consistent with the timing of recognized historical climatic episodes, such as the Roman Warm Period, the Dark Ages Cold Per…
Integrated varve and pollen-based temperature reconstruction from Finland
A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (summer-winter) reconstructions of past precipitation and temperature fluctuations. Comparing seasonally resolved varve records with pollen-based sum of growing degree-days (GDD) reconstructions from Lake Nautajärvi, we examined the intra-annual nature of climate variability in central southern Finland during the Holocene. The organic varve record and …
Palaeosecular variation of the Earth's magnetic field during the last 10000 years based on the annually laminated sediment of Lake Nautäjarvi, central Finland
A palaeomagnetic study of the Lake Nautajärvi sediment sequence in central Finland demonstrates that varved lake sediments can provideregionally applicable secular variations curves for Holocene stratigraphic correlation and age control. Based on x-ray radiography and digital image analysis techniques we constructed an inherent and continuous varve chronology for the Lake Nautajärvi varve sequence, which covers nearly 10000 years with an estimate…
Neoglacial activity in Finland
Palaeomagnetic dating of sediment sequences from lakes Pihtsusjärvi and Haltijärvi in Enontekiö, northwestern Finnish Lapland, provided a chronology for a study of the palaeohydrological and glacier history of the Halti-Ridnitšohkka fells area. Both sequences exhibited a stable primary component of the NRM direction, allowing a comparison of the secular variation records with the chronology of Lake Nautajärvi reference curves (NRM) to provide a c…
History of agriculture in Mikkeli Orijärvi, eastern Finland as reflected by palynological and archaeological data
Integrated varve and pollen-based temperature reconstruction from Finland
A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (summer-winter) reconstructions of past precipitation and temperature fluctuations. Comparing seasonally resolved varve records with pollen-based sum of growing degree-days (GDD) reconstructions from Lake Nautajärvi, we examined the intra-annual nature of climate variability in central southern Finland during the Holocene. The organic varve record and …
Calibrated pollen accumulation rates as a basis for quantitative tree biomass reconstructions
Recent investigations show that the pollen accumulation rate (PAR) of the common tree taxa is directly related to the biomass and, by inference, to the population size of the taxa around the study site. Fossil PAR records preserved in lakes provide therefore a potential proxy for quantitative biomass and population reconstructions. We use the high-resolution PAR records obtained from two accurately dated lake sediment cores in Finland to generate…
The history of settlement on the coastal mainland in Southern Finland. Palaeoecological, archaeological, and etymological evidence from Lohjansaari Island, Western Uusimaa, Finland
Meteorological validation of chironomids as a paleotemperature proxy using varved lake sediments
In order to improve the reliability of climate models in their projections for the future, spatially and temporally detailed paleoclimate proxy data are needed. In this study, we examined annually laminated sediments from Lake Nurmijärvi (Finland) for their fossil Chironomidae assemblages over a time period with available meteorological observational data (since 1830s). In doing so, we correlated chironomid-based inferences of summer air temperat…
A 5500-year oxygen isotope record of high arctic environmental change from southern Spitsbergen
The oxygen isotope composition of chironomid head capsules in a sediment core spanning the past 5500 years from Lake Svartvatnet in southern Spitsbergen was used to reconstruct the oxygen isotope composition of lake water (δ 18 O lw ) and local precipitation. The δ 18 O lw values display shifts from the baseline variability consistent with the timing of recognized historical climatic episodes, such as the Roman Warm Period, the Dark Ages Cold Per…
Neolithic land use in the northern Boreal zone
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datin…
Proxy-based 300-year High Arctic climate warming record from Svalbard
We used fossil Chironomidae assemblages and the transfer function approach to reconstruct summer air temperatures over the past 300 years from a High Arctic lake in Hornsund, Svalbard. Our aims were to compare reconstructed summer temperatures with observed (last 100 years) seasonal temperatures, to determine a potential climate warming break point in the temperature series and to assess the significance and rate of the climate warming trend at t…
The environment they lived in
Understanding about regional versus local changes in vegetation is critical in answering archaeological questions, in particular at a time when humans are assumed to have caused higher disturbances at local scales rather than regional scales; this is the case during the Neolithic. The aim of this paper is to assess the impact of Neolithic land use on regional and local vegetation dynamics, plant composition and disturbance processes (e.g. fire) i…
Environmental history recorded over the last 70 years in Biển Hồ maar sediment, Central Highlands of Vietnam
A high-resolution, 1250-year long drought record from Ea Tyn Lake, Central Highlands of Việt Nam
An understanding of past climatic variability at regional to local scales is mandatory for a proper evaluation of current and potential future repercussions from global climate change. The Southeast Asian tropics remain severely under-represented in paleoenvironmental and paleoclimatic reconstructions, although a few recent paleoclimate studies evaluated the variability, position and strength of the main Asian monsoon systems at different timesca…
Varve series cross-correlation and palaeosecular variation from two clay varve basins in western Estonia
Geology and Paleoclimatology Research (14 works) · Geography (12 works) · Geology (11 works) · Physical geography (11 works) · Holocene (7 works) · Oceanography (7 works) · Paleontology (7 works) · Archaeology (6 works) · Climate change (6 works) · Ecology (6 works)