How will cryospheric changes at the poles impact polar terrestrial and marine ecosystems and the Earth’s climate?

Global climate change is heavily noticed at the poles. Sea ice diminishes, ice shelves collapse and ice sheets shrinking as ice melts and glaciers accelerate. Consequences are manifold:

A large subglacial hydrological system exists beneath the Greenland and Antarctic Ice Sheet. Across this system the ice and water interacts with the underlying lithosphere and biochemical processes mobilizing nutrients which are subsequently transported to the ocean. Hidden beneath kilometer thick ice these interactions are not yet studied, neither the flux quantified nor the faith of nutrients in the ocean is known. Yet processes, like mobilization of iron from fine glacial flower, could play a role in fertility of the polar ocean.

Changes in the extent of polar ice coverage exposes large areas of ocean floor to an open ocean or to semi perennial ice coverage as well as large continental areas. This exposes large areas to sun light and allows photosynthesis. Changes in the availability of light will change the food web and nutrient supply. Photosynthetic communities will likely replace chemotrophic communities. Unknown are the effect on the marine food web, global chemical cycles and feedback to the Earth Climate system. Especially understudied in this regard is the ecosystem of the polar oceans. To detect and quantify change here, a base line needs first to be established.

Glaciers and sea-ice at the poles also play a crucial role for the global circulation of the ocean. Increased melting at the poles will freshen the ocean impacting thermo hyaline circulation. A similar effect will have shrinking sea-ice extend and collapse of ice shelves. Yet many of these processes are not yet well understood. (see Global Water Cycle question)

How do the dual effects of greenhouse gases on the ocean (warming and acidification) interact with local stressors (overfishing and pollution) to reduce ecosystem services and cause extinctions?

The ocean covers 70% of the planet, yet the dual impacts of greenhouse gases are typically ignored – e.g. solutions designed to reduce heating without reducing CO2 concentrations ignore the threat posed by acidification. Moreover, we know little about the synergies between local and global stressors, and how reducing the former might buy us time to deal with the latter.

What are the heat content and net thermal flux of the ocean basins, and how are they changing over time?

The answers are necessary for accurate climate modeling. The difficulty will be the expense of placing and monitoring the large number of sensors required (at least tens of thousands, perhaps many more).

How and why is the cryosphere changing? How are these changes impacting people and eco-systems around the planet? What can be done to ameriolate these changes?

The cryosphere is one of the most dynamic, least sampled and least understood components of the Earth system. Changes in the cryosphere impact the water supply for millions, if not billions of people on the planet and seriously alter the availability of water for industry, irrigation, consumption and sanitation. Changing sea level *will* impact those on the coast, changes in seasonal snow cover will impact regional climate and the Earths albedo. Changes in the Earths polar ice sheets are alarming, but not yet fully understood. Changing ice and snow affects all other aspects of the Earth system – ecology, geology, hydrology, atmospheric science, marine systems, social systems, economic systems and human health. We cannot ignore the cryosphere. Obstacles – perceived relevance to the science funding agencies of tropical countries, politics of high latitudes, resource management challenges. In my opinion decreasing water supplies will be the cause of future international tensions.

How much potable water can be extracted from sea water that is safe to drink?

Different experiments are being performed to obtain potable water from sea water. Procedure seems to be expensive. No records are available about its side effects, if any. It is not known that such drinking water will be cheaper or not. If it is cheaper to make then third world countries, poor countries many african countries and asian countries would benefit.

How will anthropogenic factors change local weather systems? Where are the areas most vulnerable to a change in the weather which could significantly affect the ability of their human population to survive?

Any change in the climate system will affect different areas to different extents. Some places (particularly in poorer countries) rely on growing food locally and do not have the infractructure to deal with large weather fluctuations. We need to understand how changes in large atmospheric and oceanic systems affect weather on smaller scales in order to provide support to those communities and protect nearby wildlife habitat.

What kind of secure remediation can be used if carbon continues to rise in atmosphere?

The world is changing and, despite governments has adopting an ecologically suitable speech, not enough concrete attitudes have been taken to avoid global change. So, Scientist needs to search for a worst but necessary alternative: the remediation of the continuously increase of the carbon concentration in the atmosphere. There are propositions in this way, as enrich oceans with iron to increase grow of algae that will absorb carbon, but are these alternatives harmless? So, profoundly studies of these alternatives are imperative.

How water is transformed globally between the ocean, land and the atmosphere?

Water is the most important nature factor for human life. It influences the human life directly. It is also the main driver of the climate. Although we do not have the global water budget information yet, but very close to have it. What we need is from space to monitor globally the atmosphere water content, the ocean salinity, the precipitation, the land soil moisture, the ground water run off, the polar ice melt, the underground water distribution and variations. We already have GRACE mission to monitoring the underground water distribution and variations, the polar ice melting, SMOS mission and SMAP mission will be launched soon to monitoring the land soil moisture and ocean salinity, FY3 and other weather satellites to monitoring the atmosphere water content, etc. However, the data are not integrately studied together and a more complete constelation of these kinds of satellites with higher tempo resolution are needed if we want a complete answer of this question. A global cooperation with participation of many governments like US, Europe, Russia, China, Japan and India is necessary!

If the atmospheric CO2 content is increasing due to anthropogenic activities causing possible climate change then has the world oceans reached their limits as CO2 sink?

Over the geological past the world oceans have acted as veritable sinks of atmospheric CO2 that caused the formation of various carbonate deposits. This also had modulated the past climates. The relative efficacy and global-scale importance of oceans and forests in natural sequestration of CO2 is not known. Past ocean records however indicate that ocean waters are capable of absorbing large quantities of CO2. In this situation an answer is required for the question why the oceans are incapable of responding as CO2 sink to sequester the increasing volume of CO2 emission. We need to study physico-chemical aspects of ocean waters and ocean-atmosphere interface characters to get an answer.

What is the contribution of groundwater to ocean and seas?

Understanding and modelling the oceans and seas water cycle requires quantifying all water fluxes entering or leaving the ocean system. Groundwater fluxes are not well known and their underestimation can cause overestimation of other fluxes or errors in the ocean modelling calibration.