Processes Influencing Carbon Cycling: Observations of the Lower limb of the Antarctic Overturning (PICCOLO)

GSTDTAP

项目编号	NE/P021395/1
	Processes Influencing Carbon Cycling: Observations of the Lower limb of the Antarctic Overturning (PICCOLO)
	Karen J. Heywood
主持机构	University of East Anglia
项目开始年	2017
	2017-07-31
项目结束日期	2021-07-30
资助机构	UK-NERC
项目类别	Research Grant
国家	英国
语种	英语
英文摘要	The vast, remote seas which surround the continent of Antarctica are collectively known as the Southern Ocean. This region with its severe environment of mountainous seas, winter darkness, strong winds, freezing temperatures and ice is unsurprisingly one of the least explored and under-observed parts of the global ocean. However, because of these extremes, it plays a large and still unquantified role in Earth's climate system. In this region, large amounts of heat and carbon dioxide are exchanged between the atmosphere and the ocean. The physical mechanisms controlling these atmosphere-ocean exchanges are the subject of the NERC ORCHESTRA programme. We propose within PICCOLO to concentrate on the role that chemistry and biology play within those exchanges. In particular, PICCOLO will focus on understanding the mechanisms that transform the carbon contained in the seawater as it rises to the surface near Antarctica, interacts with the atmosphere, ice, phytoplankton and zooplankton inhabiting the near surface, before descending to the ocean depths. PICCOLO will undertake an ocean research expedition to the region close to Antarctica, as computer models and satellite images show that these are areas crucial for carbon processes. Freezing seawater in these regions releases salt into the water below, making it denser and therefore causing it to sink. Strong winds cause the sea ice to be pushed away from the Antarctic coastline, leaving areas of open water called polynyas. Within the polynyas the water has enough light during the summer to allow phytoplankton to grow, as well as providing dense waters which sink to the deep, driving a giant ocean conveyor belt which has a large impact upon Earth's climate system. The PICCOLO team will measure the key variables that control the biological and chemical processes in this region including iron, nutrients, phytoplankton and zooplankton. Crucially the team will study the controlling rate terms between different parts of this biological and chemical system. The PICCOLO team will make use of the latest technologies, including autonomous submarines, gliders and floats, to observe these processes in otherwise inaccessible and previously unstudied areas such as under the sea ice. Most ambitiously we will anchor a submarine to the seabed within a polynya and leave it over a winter season to collect data, recovering it the following spring. The PICCOLO team will put instruments on seals which will continuously take data as they dive up and down through the water, sending it back to scientists in real-time via satellite communication links. This wealth of novel data will be analysed by the PICCOLO team, using state of the art computer models, to test our ideas about how the whole complex set of physical, chemical and biological processes affects carbon. Conceptually we will follow an imaginary parcel of water through the system looking at processes between the atmosphere and ocean, biological processes in the surface layer, exchanges between the upper and lower ocean and the final fate of the carbon. The PICCOLO hypotheses address the following: (i) Factors controlling the exchange of carbon dioxide between the ocean and atmosphere and the role of ultra-violet light in controlling the concentration of carbon dioxide in seawater; (ii) The role of light, iron and nutrients in how carbon is processed by the plankton in the water; (iii) The mediating processes governing the export of carbon from the upper ocean to depth; (iv) The processes that take the carbon into the deep ocean on the next stage of its global journey.
来源学科分类	Natural Environment Research
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/86770
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Karen J. Heywood.Processes Influencing Carbon Cycling: Observations of the Lower limb of the Antarctic Overturning (PICCOLO).2017.