tag:blogger.com,1999:blog-2249983551893842827.post8783108167220252157..comments2023-10-26T23:39:36.158+01:00Comments on Climate and Stuff: Satellite Temperaturesthefordprefecthttp://www.blogger.com/profile/07210786222021457913noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-2249983551893842827.post-52243429725283900092015-01-08T18:28:07.286+00:002015-01-08T18:28:07.286+00:00Hi Victor
from a document from the site reference ...Hi Victor<br />from a document from the site reference on the plot:<br /><br />http://bluemoon.ucsd.edu/publications/ralph/Keeling_et_al_Tellus_07.pdf<br /><br />The primary O2/N2 reference gases (or ‘primaries’) used at<br />Scripps consist of 12 tanks filled between 1986 and 1989, and<br />an additional set of six filled between 1993 and 1994, as summarized<br />in .....<br />The large size of the atmospheric O2 reservoir makes measurements<br />of the relatively small changes in O2 concentration<br />challenging. Resolving a land biotic sink of 2 Pg C requires the<br />ability to detect a change of ∼1.8 × 1014 moles in the global<br />O2 abundance, which corresponds to 0.000 49% of the total burden<br />of O2 in the atmosphere. Changes in O2 concentration are<br />typically expressed in terms of the relative change in O2/N2 ratio<br />δ(O2/N2) = (O2/N2)sample/(O2/N2)reference − 1,<br />where δ(O2/N2) is multiplied by 10e6 and expressed in ‘per meg’<br />units. In these units, a change of 1.8×10e14 moles in the globalO2<br />abundance corresponds to a change of 4.9 per meg. In spite of the<br />measurement challenge, there are now at least six independent<br />O2 measurement techniques in use that have demonstrated a<br />precision at the level 6 per meg or better (Keeling, 1988a; Bender<br />et al., 1994; Manning et al., 1999; Tohjima, 2000; Stephens et<br />al., 2003; Stephens et al., 2006), and these methods are being<br />variously applied for flask or in situ measurements by at least<br />12 scientific institutions.<br /><br />Hopefully this clears up the sizing problemthefordprefecthttps://www.blogger.com/profile/07210786222021457913noreply@blogger.comtag:blogger.com,1999:blog-2249983551893842827.post-14359885648578678352015-01-08T15:14:17.660+00:002015-01-08T15:14:17.660+00:00I am not sure whether I understand the axis with t...I am not sure whether I understand the axis with the O2/N2 ratio. Why is is negative? A logarithm? <br /><br />N2 is constant. Thus if the ratio had changed from -100 to 400, that would mean an enormous decrease in the oxygen concentration, which is clearly not physical. Thus I must be understanding something wrong.<br /><br />As the plot suggests the main reason for fluctuations in O2 are the fluctuations in CO2. The annual cycle of CO2 is much, much smaller than 1%; the mean concentration of CO2 already is. The O2 percentage in the atmosphere is almost 20%. Thus one would expect that the fluctuations in O2 are much smaller than the mean concentration of O2. To me it seems a reasonable assumption to keep it constant in the temperature retrieval. This retrieval has much bigger other problems.<br /><br />It is really funny that the mitigation sceptics are so fond of their satellite measurements. These tropospheric temperatures are the most heavy temperature dataset we have. Normally the mitigation sceptics complain about adjustments. For political reason the tropospheric temperatures are naturally better for them, the dataset is short and the trend is relatively small. However, normally the mitigation sceptics claim to be the only true guardians of science. Something there does not fit together.Victor Venemahttps://www.blogger.com/profile/02842816166712285801noreply@blogger.com