afrirpa 2010, sources, processes and fate of environmental radioactivity

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Sources and fate of environmental radioactivity at the earth’s surface Farid El-Daoushy, Department of Physics and Astronomy, Uppsala University, Sweden Objectives: To link environmental radioactivity to RP in Africa? To describe the benefits of Africa from this field in terms of RP, safety and security policies. To create a mission and a vision to fulfil the needs of ONE PEOPLE, ONE GOAL, ONE FAITH.

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Invited plenary talk given by Prof. Farid El-Daoushy at Inter. Radiation Protection Congress, Afrirpa-2010, Sept. 2010, Nairobi, Kenya.This talk summarizes the sources, processes and fate of environmental radioactivity (natural and artificial) at the earth\'s surface. It links environmental radioactivity to radiation and environmental protection issues in Africa. The role of global and regional processes on the transport and accumulation of anthropogenic waste in complex ecosystems, e.g. the Nile Basin, are described. These issues help fulfilling the African mission and vision for achieving their golals: ONE PEOPLE, ONE GOAL, ONE FAITH.

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Page 1: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Sources and fate of environmental radioactivity at the earth’s surface

Farid El-Daoushy, Department of Physics and Astronomy, Uppsala University, Sweden

Objectives: To link environmental radioactivity to RP in Africa? To describe the benefits of Africa from this field in terms of RP, safety and security policies. To create a mission and a vision to fulfil the needs of ONE PEOPLE, ONE GOAL, ONE FAITH.

Page 2: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Sources, processes and fate of environmental radioactivity

(1) Factors influencing cosmogenic radionuclides

(2) Factors influencing artificial radionuclides: (a) nuclear weapon-tests

(b) nuclear accidents (c) Energy, mining and industrial waste

(3) Factors influencing the global Rn-222 and its daughters.

(4) Dynamics of cycles of natural radioactivity, e.g. Pb-210.

(5) Environmental radiotracers act as ”DIAGNOSTIC TOOLS” to assess air and water quality and impacts of the atmospheric and hydrospheric compartments on ecosystems.

(6) Definition of base-lines for rehabilitation and protection

Previous experience helps setting up an African agenda

Page 3: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Sources, processes and fate of environmental radioactivity

Nuclear Weapons Tests

Sources

Sinks

Transport

Chemistry

Cosmogenic Radio-isotopes

Human Activities

BiogenicActivity

UndergroundProcesses

VolcanicEruption

Tracers

Polar Ice Ocean Sediments

Corals Deltas& Soils

Lake Deposits Plants Ground

Water Peats Glacier LoessDeposit

Cs-137, Sr-90 C-14, Pu-238, .

Be-7, Be-10, C-14, I-129

Pb, Hg, soot,CO2, CH4, NOx,

S-, N-, P-comp., CO2, CH4, ..

U/Th, Ra-226, Rn-222, Pb-210

Dust, CO2

Radio-activity to trace natural and human impacts

stratosphric-tropospheric exchange

water cycle

interhemispheric mixing

assimilation

dispersionevaporationmelting

precipitationatmospheric circulation

ocean circulation

air-seaexchange

fractionation

Farid
Page 4: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Rn-222 Pb-210 +

Ra-226 U-238 Pb-210

Be-7, C-14, Be-10

Premordial nuclides Cosmogenic nuclides

Rn-222

Natural radionuclides are elegant atmospheric tracers

What is our knowledge on such tracers in African eco-system?

Page 5: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

U-238 and the global production of radon

small-scale emanation large-scale exhalation

Do we have an African map on the production and atmospheric behaviour of Rn-222 and daughters

Page 6: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Pu-238, Pu-239, Pu-240, Cs-137, Sr-90,..

Artificial radionuclides from atomic bomb tests

Knowledge on behaviour and fate of these nuclides in African ecosystems is needed through collaborative research with Africans. Safety and security requires preparedness.

Page 7: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Short-term transport/deposition of Chernobyl Cs-137 through tropospheric and boundary-layer processes

Page 8: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Global aerosol emissions: C, CO2, SO2, NO2, Pb

Climate influences sources/behaviour/fate of environmental radioactivity. Impacts on life forms in Africa would be severe. Assessing environmental radioactivity resolves these issues.

Page 9: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Global trajectories of air masses

Africa is a continent with symmetrical land around the equator, latitudes 30⁰ south and 30⁰ north

Page 10: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Rn-222, Pb-210

Be-7, Be-10

Aerosol dynamics: formation, growth, attachment (sources transport/chemistry deposition)

Understanding dry-wet removal pattern of environmental radioactivity in the atmospheric compartment of the Nile Basin is important for both fundamental and applied research needs.

Page 11: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Large-scale and long-term transport and chemistry processes bring soluble, particulate and collides to surface water bodies

Coupled evaporation-precipitation and surface-ground water interaction have new climate/human impacts in the Nile Basin

Page 12: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Cloud formation Water fall Mountain lakes

Agricultural/forest landInland lakes

Studies of cloud, rain and surface-water processes in Europe

Page 13: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Interactions in water bodies, e.g. lakes and rivers,depend on the involved sub-compartments

Page 14: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Natural analogues for nuclear waste studies

NORM-industries and deep geological depositories impose new threats for coupled surface-ground water Interactions

Page 15: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Behaviour of U-series nuclides in glacial deposits above the bedrock

Page 16: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

The Nile Basin involves complex interactions with

several spatio-temporal scales.

Studies of climate and environment

impacts need coordination of a

wide-range of facilities/resources.

Page 17: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Studies of Complex river systems in AfricaBehaviour of radioactivity in these ecosystems has coupled environment-climate dimensions.

Eco-system dynamics in regional/global scales

Up-scaling from small-scale to large-scale

Threats from humans, energy and industry

Coupled effetcs from environment and climate

Major issues to consider in these studies:

Page 18: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Comprehensive Test Ban Treaty ”CTBT”: global watching gamma spectrometers

”CTBT” global watch can be extended with African units to build multi-tracer databases:

- to follow environmental radioactivity in Africa

- to develop, validate and test models in Africa

- to support climate impact studies for sustainability of African natural resources.

Page 19: Afrirpa 2010, Sources, processes and Fate of Environmental Radioactivity

Conclusions

Thanks for your attention.

Understanding radioactivity in Africa has basic/applied input:

- Filling huge data-gaps in global environmental radioactivity- Filling huge gaps on the behaviour of radioactivity in Africa- Assessing climate-environment impacts in complex rivers- Assessing global cycle of Sahara dust & impacts on climate- Assessing climate-environment impacts on natural self-cleaning

- Understanding major impacts of climate in Africa on: sustainability of environment and ecosystems, e.g. erosion of fertile land, salination of freshwater, changes in evaporation-precipitation, dry-wet periods and spatio-temporal dynamics of flooding, coupled ground-surface water interactions, impacts of mining, industry and land-use on air and water quality as well as quality of food-chain and biodiversity.