Tuesday, February 24, 2009

Making electricity

Dear Children -

Did you know that electricity can be made from anything that creates constant motion? One of the most common ways to make electricity is to use the motion of water falling, like a waterfall, and change the energy of that movement into electric power that is then sent through wires to homes and businesses. A huge waterfall can provide enough energy to supply electricity to many cities.

Another way to make electricity is to use heat to provide the energy that is turned into electric power. A popular method in the United States is to burn coal for its heat, but this is a polluting method that produces lots of carbon dioxide. This is one of the reasons that anyone who wants to fight global warming needs to use less electricity every day. We need whole cities to use less electricity.

Clean ways to make electricity include the giant windmills that we can see now along mountain ridges and in the ocean near the shore. Today I read about a way that a college in California is making electricity: when hundreds of students go to the fitness center to walk on treadmills and ride stationary bikes, the college captures the energy from all that motion to make electric power. Isn't that super?

From Nana Greta


Tuesday, February 17, 2009

My husband, the photographer


Today I want to introduce my husband to you because I want to give him credit for two of the photographs on this blog. My husband's name is Guy, and he's been taking photos since his uncle gave him a camera when he was a boy. 

He took the picture of the jaguar, at the top of this page, in the zoo in Brasília, the capital of Brazil. Jaguars live in Brazil, in the forests on the high plains of the central plateau and in the rainforests of the Amazon. I wonder how they're getting along and if climate change will be hard on them.

Guy also took the picture of the oil refinery in yesterday's entry. We were near Houston in Texas, where oil is one of the main industries. Do you think the refinery looks like it's good for the environment? 

Monday, February 16, 2009

A bit of geography

Dear Children -

Yesterday I had good conversation with a geographer out on a farm in the interior of Brazil. We talked about global warming and he agreed that it was a serious problem that will affect millions of people, especially in poor communities in Europe, Africa and Asia where they depend on water from melting ice from the mountain tops. If the climate warms up a lot there will be no more ice caps to provide water for drinking and farming.

Then my geographer friend told me something that I'd been thinking might be true: Millions of years ago, in order to keep a steady climate, our planet covered up materials like dead trees that were letting off hot gases. For a long time they remained buried under the surface of the earth where their gases were trapped, and slowly they turned into oil, gas and coal. Not too long ago, humans discovered that they could dig up those materials and burn them to heat their homes, and to make engines work in factories and in cars. We discovered more and more uses for them and kept digging them up faster and faster, burning them more and more. 


Now we are realizing that all those carbon gases are causing our atmosphere to heat up in a way that is changing the climate. All the plants and animals, including human beings, that had gotten used to the planet the way it was, now have to find new ways to exist or they will become extinct. It's not too late to turn things around and keep it from getting too bad. This was the geographer's lesson. 

I think that human beings are very intelligent and creative, and it was amazing that we discovered how to use coal, oil and gas. But now we have to think again about what we're doing. We can just go on using those carbon materials and heating up the atmosphere, or we can cut back on using them, and find other ways to take care of our needs.

Nana Greta

Wednesday, February 11, 2009

The route for my walk

Dear Children -
This Google Map shows the route that I plan to follow from Galveston, Texas, ( the green A bubble at the bottom of the map) to Rouses Point, NY, (the green B bubble at the top). 


When I start out in March I will post maps that will show the routes more clearly. This map just gives you a general idea of where I will walk. It measures approximately 2000 miles. I plan to walk an average of 12 miles a day. I'll let you figure out how many days it will take me.
Love, Nana Greta

This blog is for you

Hello. My name is Greta and I'm 65 years old so you may call me Nana Greta. 

I'm going to go on a very long walk - more or less 2000 miles. The reason I'm doing this is that I'm very worried about Global Warming and the bad things that can happen to the Planet Earth. I worry that life will be harder for all the children that are growing up now unless we grownups stop doing things that are bad for the world. Life will be harder for many animals too, and some of them are already becoming extinct. 

One day in October of 2008 I realized that I wanted to do something really impressive to call attention to Global Warming. That's when I decided to take this long walk. I am dedicating this walk to all the grandchildren in the world. That includes YOU.

Tomorrow I will tell you where the walk will be, when it will start and about how long it will take.