Week two: Consider

Consider:

• What are the most important themes you have learned this week?

I think that the tools and their importance to understand past climates, since valid records with measurement tools only begun after the 1950's, having of course very important  registers from the 19 th century and in the first half of the 20th century (we can even trace some registers up to the 16th century, but very rare ones). The notion of how or primarily hot planet went trough several climate chances including several ice ages and it's the self regulating mechanisms. Also a bit of basic chemistry, essential to understand the readings of those data

• What aspect of this week did you find difficult?

The chemistry. It was a bit complex. And I'm still trying to better understand isotopes, for example. I also found that it was a bit longer than the other week. I couldn't read and see the videos in 5 hours or even 8. And I'm sure I didn't grasp everything for sure. How did I miss the pollen as a proxy record?

• What did you find most interesting? And why?

Drop-stones. It was something I never notice before and I'm sure it's something that I'm going to better notice in my walks near the seaside in Portugal.

• Was there something that you learned this week that prompted you to do your own research?

Yes like the Pangaea theory.  

• Are there any web sites or other online resource that you found particularly useful in furthering your knowledge and understanding?

Eddy Cartaya: My glacier cave discoveries

Past Climate Records.

What are climate change records?

Climate change records are data that can help us understand, measure and predict weather trough out the years using either proxy measurements  - like tree rings, ice cores, boreholes in oil-drilling or coral observation - or measure tools - like weather balloons, data from satellite, equations or statistical algorithms, overlapping data from ground -base data from weather stations, etc. 

How do volcanoes affect climate change?

They effect trough a negative feedback where the earth released the pert of the core's heat in the form of magma. But they also release to the atmosphere ashes, sulphor dioxide and sulfates. They create a form of aerosols that darken and spreads out in the atmosphere, provoking a cooling of the climate by blocking out solar radiation. But this has a short time effect.

How is today’s warming different from the past?

There is a new component in game. Not as much as new as a new record of it: CO2. In the last century the CO2 concentration increased heavily. We might correlate it with the extraordinary rise of temperature trough out the last century.

What is the role of isotopes in determining temperatures from the past?

Calcium carbonate, one of the elements found for example in the layers of  sediments relates to the acid rain that proceeds the accumulation of carbon dioxide and other gases released by volcanoes after a ice age. The carbonate have the presence and concentration of  of isotopes that allow us to read past temperatures.

How have trees been used to reconstruct different climate variables across the world?

They are a valid evidence of past climate and serve as proxy records, either with the use of an incremental borer, that pierce the tree and take a sample that allow us to study climate changes in the tree rings (hot summers the tree has a greater vigor, cooler ones it has fain rings, or with the observation of dead trees (ones that were cut long time ago for example). 

How can ice cores provide a record of atmospheric composition?

They serve as proxy records as well, and a source of evidence of past climate. They register seasonal snow layers, that can provide information trough the observation of several bore holes sample of temperature, precipitation, atmospheric pollution, wind patterns and even volcanic activity .Isotopes measurements are also very important, giving the concentration of oxygen and relating it to a given temperature. But also the chemistry reading of methane can indicate a of of bacteria, or the presence of ashes can be use to indicate the presence of volcanic activity or wind strength.

Week one: think about...

At the end of the module we were asked to reflect and considerate some points.

Reflect on these key questions:

• What the key scientific principles that explain climate change including the greenhouse (blanket) effect?

The measurement of weather condition (and solar energy and radiation), trough a period of time, by the observation of the earth components (atmosphere, biosphere, cryosphere, hydrosphere and lithospher).

• What are the key feedback mechanisms that help to explain why our climate is able to “self-regulate”?

The positive and negative feedback's, the ones that amplify the effect of a change on climate forcing or diminish it, like the water vapor feedback, the ice albedo feedback, or a volcanic eruption (Earth crust cooling system?).

• How can our climate be conceptualised as a system containing a series of components that interact with one another?

By studying the relation between atmosphere, hydrosphere, biosphere, cryophere and lithosphere,  we can come up to a valid scientific mensurable observation of the weather variation trough a longer period. 

Also consider:

• What are the most important themes you have learned this week?

The notion of the climate system and its elements , greenhouse effect opposed tho Earth blanket, what is albedo ans feedback mechanisms.

• What aspect of this week did you find difficult?

I was a bit afraid of being able to go trough the content within the week. I'm taking another future learn course, and "my week" only start on Wednesday. I usually don't have internet on the two days before. Still With a bit on my plate (work, second language, home tasks and 2 courses I feel it very rewarding, and totally worth it. 

• What did you find most interesting? And why?

The more accurate blanket effect opposed to greenhouse effect. Very well illustrated. Also the fact that water vapor has a big role in climate changes, preventing the solar radiation to escape to space.

• Was there something that you learned this week that prompted you to do your own research?

Sure like: James Hansen: Why I must speak out about climate change

• Are there any web sites or other online resource that you found particularly useful in furthering your knowledge and understanding?

Ted talks.