Comments Cara_J has made

  • Thank you, kceridon! Here is my quick, not-too-technical explanation (hoping my advanced degrees in chemical engineering have led me to an accurate one) A freezer is definitely NOT more efficient when empty. The room full of people analogy doesn't work. People are alive and constantly generating heat. Food items in your freezer are NOT generating their own heat. In fact, a full freezer should use less energy. An empty freezer is full of air, which has some mass but nowhere near the mass of all those food items. The freezer is working all the time to remove heat from inside the freezer to the outside. Once food items are frozen, they will lose heat only slowly to the outside when the door is opened. The freezer thus doesn't have to work as hard. Air, on the other hand, not only heats up more quickly but also physically moves in and out of the freezer when door is open, mixing with warm air. However, don't pack in foods too tightly in the freezer. Air needs to circulate around items to help cool them down.On Ask Umbra on canned and frozen foods posted 1 month ago 23 Responses
  • Kristen, I'm responding to just one point here. "No one intentionally raises a child to love Hummers" ? You bet they do. Have you ever spent time in the smaller cities or towns that make up mainstream America? I currently live in a Midwestern county that is a mix of Democrats and Republicans. I am amazed at the values people pass on to their children. They let their kids ride along while mowing sprawling lawns with big, emissions-spewing riding mowers. Then they get out the gas-powered leaf-blower. Then the weed trimmer. They buy the kids (electric, noisy) toy cars they can actually drive, replicas of SUVs or Jeeps or, yes, Hummers. Families wash their cars and SUVs in the driveway, letting soap and water run into the storm sewer without any regard for the effects in streams. You get the idea. No one can convince me that parents' eco-values or consumerist values don't typically get passed on to their children. Of course there are exceptions, as you say. But in general, parents' values have deep, lifelong impact, for better or for worse. Thus there is validity to the point that parents who actively work to reduce their families' footprint are doing less harm than those who have kids and raise them to be careless consumers.On Ask Umbra on big families posted 2 months, 2 weeks ago 48 Responses

  • The "best" lawn may be very different in different climates.  Where I live in the Midwest, vegetation explodes with growth in spring and summer.  If we did nothing, the plants (whether native prairie or the "weeds" that grow in disturbed areas) would soon be taller than our young children and too thick to walk through.  Fun for exploring, perhaps, but no good for games of frisbee or football or for hanging laundry out.  And the prickly bushes are pretty brutal.  Therefore I think cutting part of the lawn during the growing season makes sense--but not with a gas mower!  I would love to know of low-lying ground cover plants that would thrive in my area, to further reduce mowing.  I pull the prickly weeds by hand.  

     And like I said, we never water or chemically treat our grass-covered lawn even though all our neighbors do.  The difference in appearance is not dramatic.

    On The perfect lawn doesn't require a gas-powered mower posted 4 months, 2 weeks ago 10 Responses
  • Both commenters above have good points. Regarding the first comment, however, an electric mower will still produce far less pollution than a gas mower even if the electricity is from coal. Regarding the second comment, I'll ignore the annoying all-caps and agree heartily. Let's move beyond a sea of grass and include a variety of hardy, low-maintenance ground covers. Americans are not ready for "no lawn" at all, but we should forgo the weed-killers and synthetic fertilizers and accept a much less "perfect" lawn, as well as choosing electric or manual mowers. And in wetter parts of the country, watering is not necessary. Grass goes dormant in the hottest period, then recovers. Yet many people water all summer long.

    I've used a manual mower for two years, except for about 3 occasions when we've let it get too long and had to borrow a conventional mower. The manual mower has some wonderful advantages but also a downside: It won't cut very long grass, wet plants, or various other plants/weeds--a problem for those of us who don't treat with chemicals. It's a workout and takes longer.On The perfect lawn doesn't require a gas-powered mower posted 4 months, 2 weeks ago 10 Responses

  • The sunscreens that appear white likely do so because they have larger particles of titanium dioxide and/or zinc oxide.  This might be a good thing.  Many sunscreens contain nano-sized particles of these minerals because in that case the sunscreen rubs in without looking white.  We know very little about the effects of nanoparticles, which can easily be absorbed through skin, in the human body.  Until we know more, I try to find sunscreens with "micronized" titanium/zinc oxide or, if they don't say that, that look white on the skin.  (There's a pricey but good one from California Baby.)  So complicated!

    On A sizzling test of seven eco-sunscreen brands posted 5 months, 3 weeks ago 3 Responses

  • missing the point

    meadow20, I don't think anyone is suggesting that everyone in the US switch all their meat-eating to venison.  Americans currently eat a rather excessive amount of beef and poultry and could make a real improvement in both environmental and personal health if they significantly reduced their meat consumption.

    Eating hunted deer may make sense if you live in one of the many areas with a high deer population.  On Umbra on homegrown meat posted 11 months ago 33 Responses

  • We use gdiapers, a great alternative!

    Umbra, as jdriscoll pointed out, there is a great alternative with a lot less washing involved: gdiapers, which have flushable/compostable liners.  I use these on my baby and compost the wet ones. Thus I only flush about one per day (in the newborn weeks it was more).  

    Although they're not perfect, I'm betting in another decade or two they'll be as leak-free and easy as disposables, which have had decades of development to improve.  Hooray for gdiapers taking on the enormous challenge of a low-impact diaper, up against the disposables behemoth.  (And yes, we do use disposables now and then when it's more convenient.)On Umbra on the never-ending diaper ado posted 1 year, 5 months ago 25 Responses

  • Take a look at the study -- it's flawed.

    I am amazed that Umbra quoted the conclusions of the study without taking a look at the study itself.  The study has serious flaws, as other posters have noted.  (For example, they compared the manufacturing impact of cloth vs disposables, even though the cloth nappies get used over and over and over! Not a valid comparison.)On Umbra on the never-ending diaper ado posted 1 year, 5 months ago 25 Responses

  • No need to be suspicious of ACS

    Folks, please do your research before commenting.  The American Chemical Society (ACS) is a scientific membership society.  They do NOT make fertilizers or any other chemicals.  They publish academic research journals and run academic conferences for ultra-nerdy scientists (like me).  They also provide fellowships and awards and administer some research funding.

    ACS publishes the journal ("Environmental Science & Technology") that the food-miles study was reported in.  Hence the copyright.

    Here are a few of the dozens of other journals published by ACS:
    Bioconjugate Chemistry
    Nano Letters
    Journal of Physical Chemistry
    Chemical Research in Toxicology
    Industrial and Engineering Chemistry Research
    Journal of Medicinal Chemistry

    You get the idea.

    If you want to know who funded the research, this will generally be stated in the "acknowledgments" section of the article.  I haven't checked this one yet.  (Don't be too quick to condemn anyone, though.  I once did research funded partly by the ACS Petroleum Research Fund that had nothing at all to do with petroleum.  In fact, the goal was improving solar cells.)

    If you google the authors, you can find out more; for example, one of the authors of the study heads the Green Design Institute at Carnegie Mellon.On Still more reasons to eat local and lay off the beef posted 1 year, 5 months ago 33 Responses