Welcome to ScienceBits

Estimate the conditions at the Center of the Sun or the Chandrasekhar Mass Limit using simply energy arguments.
A random (and subjective) walk in science and physics in particular.

In the blog and bits sections, you'll find various interesting science related anecdotes you'll find nowhere else (e.g., an exhaled breath condensation calculator, or a snow probability calculator), and also things you will (such as a pension calculator written for my needs).

In the Research section, you'll find articles which are more directly related to my personal research in astrophysics, or on the role of cosmic rays behind climate variability. For example, you'll find articles on the Milky Way and Ice-Ages, or on the question of which mechanism is behind the 20th century global warming, is it Solar or Anthropogenic?

If there are any comments about the site you would like to post, feel free to post them here.

Enjoy your stay in $  \int \hskip -2pt c_i e^n ce ~ {\Cal B}i^ts $ !

Note, you're more than welcome to post comments, however due to some flooding by spam (mostly for v-pills), some precautions were placed. There are now two options to place comments:
  1. Anonymous comments, using a captcha and moderation (i.e., after I verify and approve that the content is legit.)
  2. Register/login using a captcha, and then comment without a captcha. If the comment appears legit., the next comments will not require any approval


A friend has passed away

I just found out that a dear friend had passed away. Nigel Calder was the voice of rationality within a sea of extreme, something which is very much missing in the global warming debate. He didn't accept things for granted, but on the other hand didn't make extreme claims in the opposite direction either. He was simply driven by science (i.e., curiosity). One of his interests was of course that of climate.

The IPCC AR5 – First impressions

The IPCC summary for policy makers is out, and as I started writing these lines so was the last draft of the main report. Of course, it will take a while to digest the 2200 pages of the full report (it has a lot of starch!). Until I do, here are my first impressions from having read the summary and having skimmed the full scientific report.

Gravity waves in rain clouds over the Arava valley

Spring weather here in Israel was rather strange. Although winter with most of its precipitation should have been over, we had a few very rainy days. We're now in the midst of a heat wave with temperatures as much as 20°C higher than just a week before. In between there was a nice gravity wave appear over the Arava Valley, the first one I have ever seen in a rain radar!


Predicting a supernova precursor (on SN2010mc)

A very interesting paper recently appeared in nature. It describes the detection of a precursor eruption of a supernova progenitor more than a month before the supernova explosion itself. It is particularly interesting because this detection was not serendipitous—it was based on my prediction.

Video Lecture: Solar vs. Anthropogenic—Better Understanding of 20th Century Climate Change

Last month I participated in EIKE's (Europäisches Institut für Klima und Energie) conference on Climate Change. They video record the lectures, which means that mine is now online. I thought I'd share it with you. Have fun.

Dust Dendrites

My wife and I had our kitchen renovated. Since this involved breaking a few walls (and cutting out a new window), we knew it would raise a lot of dust. Mind you, here in the middle east houses are built from concrete and concrete blocks, not wood. To minimize the dust annoyance (and damage), we decided to quarter off the living room from the kitchen by using large nylon sheets hung from the ceiling to the floor. 

After the dust settled down (literally…), we found something quite bizarre. The nylon walls developed very beautiful dust dendrites, akin to the more familiar frost dendrites (like these frost dendrites I have seen while living in Toronto). 


The worst of the BEST

I was asked by quite a few people about my opinion on the BEST analysis of Richard Muller and his group in Berkeley. Since I didn’t want to keep my friends without an answer, I took a more careful look into the analysis. Here is what I think of it.

There are two parts to the analysis. The first part is a reconstruction of the temperature over the 20th century. The second part includes analyzing this reconstruction and drawing various conclusions out of it.


blog topic:

The eye of the Hurricane

After being busy with the submission of two research proposal and trying to stay afloat with the pretty heavy teaching load I have this semester, I decided I should take a short break and post something on my blog. I actually have quite a few things I have been wanting to write about, but it seems that the most relevant thing is the the mini-war which is raging not to far from here. So, I thought I'd stray from my usual and write about the middle east.

blog topic:

Does the global temperature lag CO2? More flaws in the Shakun et al. paper in Nature.

Over the past two weeks, perhaps a dozen people asked me about the recently published paper of Shakun et al. in Nature. It allegedly demonstrates that the global temperature followed CO2 around the warming associated with the last interglacial warming, between 20 to 10 thousand years ago. One even sent the story as a news item on NPR. So, having no other choice, I decided to actually read the paper and find what is it all about. Should I abandon all that I advocated over the past decade?


Open letter to Rep. Adam Schiff, regarding SOPA and PIPA bills.

Dear Rep. Adam Schiff (representing California's 29th district).

Although I presently live outside the US, I am a registered voter in the 29th district which you represent. I kindly ask that you will drop your support of SOPA.

blog topic:

Causes of Climate Change - Poll Results

Out of curiosity, I opened a few weeks ago a poll asking the visitors of this site, what do they think is the primary cause of global warming. 429 people answered the poll (thanks to all of you!).

The results can be summarized as follows.

First, the visitors of this site have the following background:
Background Fraction (Votes)
Layman 54.9% (232)
General Scientist 41.1% (174)
Climate Scientist 4.0% (17)


On IPCCs exaggerated climate sensitivity and the emperor’s new clothes

A few days ago I had a very pleasant meeting with Andrew Bolt. He was visiting Israel and we met for an hour in my office. During the discussion, I mentioned that the writers of the recent IPCC reports are not very scientific in their conduct and realized that I should write about it here.


What is your expertise, and what is the cause of 20th century climate change?

Laymen, mostly anthropogenic
2% (8 votes)
Laymen, mostly natural
45% (193 votes)
Laymen, nobody knows
7% (31 votes)
General scientist, mostly anthropogenic
1% (6 votes)
General scientist, mostly natural
33% (142 votes)
General scientist, nobody knows
6% (26 votes)
Climate scientist, mostly anthropogenic
0% (0 votes)
Climate scientist, mostly natural
3% (11 votes)
Climate scientist, nobody knows
1% (6 votes)
Have absolutely no idea what to answer
1% (6 votes)
Total votes: 429

Climategate 2.0

A few weeks ago, the hacker/whistleblower has done it again. A new release of a large amount of e-mails from the same source (University of East Anglia) has surfaced in Russia. It is most likely from the same original batch because the last of the new e-mails is from 2009. Here is my perspective of things. Here are my thoughts about it.



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